[PDF] - Course outline Course outline Radiation Safety Officer Radiation PDF Document

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1

Radiation Safety Officer Radiation Safety Officer Training Class Training Class

Andrew Karam, Ph.D., CHP Andrew Karam, Ph.D., CHP paksbi@rit.edu paksbi@rit.edu

Course outline Course outline

Monday

Monday -

Scientific and technical basis

Scientific and technical basis

Tuesday

Tuesday -

Instruments

Instruments Wednesday Wednesday Regulatory stuff Regulatory stuff

Wednesday

Wednesday – Regulatory stuff Regulatory stuff

Thursday

Thursday – – The art of being an RSO The art of being an RSO

Friday

Friday – – Case studies and wrap Case studies and wrap-

up

up

A historical perspective A historical perspective Historical perspective Historical perspective

Radiation discovered in 1895 by Roentgen

Radiation discovered in 1895 by Roentgen

Radioactivity discovered by Bequerel in 1896

Radioactivity discovered by Bequerel in 1896 Radiation injury recognized by 1900 Radiation injury recognized by 1900

Radiation injury recognized by 1900

Radiation injury recognized by 1900

X-
rays and radioactivity (mostly radium)

rays and radioactivity (mostly radium) used for legitimate and quack medical used for legitimate and quack medical procedures for several decades procedures for several decades

Historical perspective (cont.) Historical perspective (cont.)

Manhattan Project gave radiation studies

Manhattan Project gave radiation studies impetus impetus

Atomic weapons testing and reactor

Atomic weapons testing and reactor p g p g accidents have had biggest impact on accidents have had biggest impact on public’s current view of radiation and public’s current view of radiation and radioactivity radioactivity

Other uses include medical, research, and

Other uses include medical, research, and industrial industrial

What this means…. What this means….

We have over a century of experience

We have over a century of experience working with radiation and radioactivity working with radiation and radioactivity

We know more about the health effects of

We know more about the health effects of

We know more about the health effects of

We know more about the health effects of radiation than about virtually any other radiation than about virtually any other harmful substance harmful substance

Anyone who says otherwise is itching for a

Anyone who says otherwise is itching for a fight! fight!

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How and where we use How and where we use radiation and radioactivity radiation and radioactivity Medical uses Medical uses

Cancer therapy

Cancer therapy

X-
ray and CT for diagnostic purposes

ray and CT for diagnostic purposes X ray and fluoroscopy in the OR ray and fluoroscopy in the OR

X-ray and fluoroscopy in the OR

ray and fluoroscopy in the OR

Radiopharmaceuticals for medical

Radiopharmaceuticals for medical diagnosis diagnosis

Radioactive immunoassay (RIA)

Radioactive immunoassay (RIA) measurements to diagnosis disease measurements to diagnosis disease

Research uses Research uses

Radioactively

Radioactively-

tagged molecules used as

tagged molecules used as tracers of biological activity tracers of biological activity

Gene sequencing

Irradiation of cells or organisms for

Irradiation of cells or organisms for research purposes research purposes

Toxicological studies (biokinetics of toxins

Toxicological studies (biokinetics of toxins and drugs) and drugs)

Industrial uses Industrial uses

Industrial linear accelerators

Industrial linear accelerators

Radiography devices

Radiography devices

Gauges (tank levels, thickness, etc)

Gauges (tank levels, thickness, etc) g ( , , ) g ( , , )

Electron and ion beams (welding, ion

Electron and ion beams (welding, ion implantation, etc.) implantation, etc.)

Well logging and soil density gauges

Well logging and soil density gauges

Smoke detectors, self

Smoke detectors, self-

illuminating signs,

illuminating signs, and other consumer products and other consumer products

Nuclear reactors Nuclear reactors

The US generates about 20% of its

The US generates about 20% of its electricity with about 100 nuclear power electricity with about 100 nuclear power plants plants W ld W ld id l 500 l t id l 500 l t

World

World-wide, nearly 500 nuclear reactors wide, nearly 500 nuclear reactors produce about 16% of the world’s produce about 16% of the world’s electrical power electrical power

Nuclear reactors are also used to produce

Nuclear reactors are also used to produce isotopes for medical, industrial, research, isotopes for medical, industrial, research, and military uses and military uses

Background information Background information

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Atomic structure Atomic structure

Atoms have a nucleus in the center of an

uter cloud of electrons
uter cloud of electrons

The nucleus contains both protons and

The nucleus contains both protons and neutrons neutrons

The number of electrons is generally equal

The number of electrons is generally equal to the number of protons to the number of protons

The number of protons is what determines

The number of protons is what determines the chemical properties of an atom the chemical properties of an atom

Protons and neutrons Protons and neutrons

Protons carry a positive charge, and repel each

ther
ther

To assemble an atom, it is necessary to have a

To assemble an atom, it is necessary to have a force to overcome the electrostatic repulsion of force to overcome the electrostatic repulsion of p the protons the protons

Neutrons carry the strong nuclear force, and

Neutrons carry the strong nuclear force, and they act as the “glue” that holds the protons they act as the “glue” that holds the protons together together

There is an optimal neutron:proton ratio to

There is an optimal neutron:proton ratio to make an atom stable make an atom stable

In general… In general…

Atoms want to have the right ratio of

Atoms want to have the right ratio of protons to neutrons to be stable protons to neutrons to be stable

As we add or subtract neutrons atoms

As we add or subtract neutrons, atoms

As we add or subtract neutrons, atoms become unstable (radioactive) become unstable (radioactive)

As the neutron excess (or deficit)

As the neutron excess (or deficit) increases, the half increases, the half-

life decreases and the

life decreases and the decay energy increases decay energy increases

decay energy versus half-life for beta-gamma emitters

half-life versus decay energy, alpha emitters

1 100 10000 1E+06 1E+08 1E+10 1E+12 3.5 4 4.5 5 5.5 6 energy (MeV) half-life (yrs) decay energy versus half life for beta gamma emitters

1.E-07 1.E-05 1.E-03 1.E-01 1.E+01 1.E+03 1.E+05 1.E+07 1.E+09 1.E+11 1000 2000 3000 4000 5000 6000 7000 decay energy (KeV) half-life (yrs)

gy ( )

What’s an isotope/nuclide What’s an isotope/nuclide

An atomic nucleus contains protons and

An atomic nucleus contains protons and neutrons neutrons

The number of protons determines which

The number of protons determines which chemical element is present chemical element is present chemical element is present chemical element is present

A nucleus may have different numbers of

A nucleus may have different numbers of neutrons neutrons

Each different number of neutrons with the

Each different number of neutrons with the same number of protons is a different same number of protons is a different isotope (or nuclide) of that element isotope (or nuclide) of that element

Examples Examples

C-
12

12

C-
14

14 P 32 32

P-32

32

Co

Co-

60

60

Cs

Cs-

137

137

U-
235

235

U-
238

238

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4

http://www.nndc.bnl.gov/chart/reZoom.jsp?newZoom=1

Radioactive decay Radioactive decay Conservation laws Conservation laws

Nucleon number

(# of protons + neutrons)

Electrical charge

Mass

Energy

Radioactive decay Radioactive decay

Some atomic nuclei have too much energy

Some atomic nuclei have too much energy

They shed this energy by emitting radiation

They shed this energy by emitting radiation Each isotope has a specific rate at which it Each isotope has a specific rate at which it

Each isotope has a specific rate at which it

Each isotope has a specific rate at which it decays and emits a specific radiation energy decays and emits a specific radiation energy

Half

Half-

life is the time in which half of a given

life is the time in which half of a given amount of isotope will decay amount of isotope will decay

Radioactive decay equation Radioactive decay equation

ln 2 A N λ λ =

1 2

ln 2

t t

t

A A e λ λ

−

= =

Units Units

Curie (Ci)

Curie (Ci) – – the amount of an isotope that the amount of an isotope that has a decay rate of 37 billion decays per has a decay rate of 37 billion decays per second (dps) second (dps) ( p ) ( p )

Becquerel (Bq)

Becquerel (Bq) – – the amount of an isotope the amount of an isotope that has a decay rate of 1 dps that has a decay rate of 1 dps

Use the “typical” modifiers (m, k, M,

Use the “typical” modifiers (m, k, M, μ, etc) , etc)

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Example problem Example problem

Assume you have a 500 mCi Co

Assume you have a 500 mCi Co-

60 source that is

60 source that is 25 years old 25 years old

Co

Co-

60 half

60 half-

life is 5.27 years

life is 5.27 years M k it th i th t M k it th i th t

1

1 60 (0.1315 25 ) 25

0.693 0.1315 5.27 500 18.67

Co yr yrs yrs

yr yrs A mCi e mCi λ

−

− − − ×

= = = × =

Make sure units are the same in the exponent

So, after 25 years (almost 5 half

So, after 25 years (almost 5 half-

lives):

lives):

Types of radioactive decay Types of radioactive decay

Alpha decay

Beta decay

Electron capture

Isomeric transition

Internal conversion

Spontaneous fission

The “purpose” of radioactive decay is to either

The “purpose” of radioactive decay is to either adjust the neutron : proton ratio or to help the adjust the neutron : proton ratio or to help the nucleus to shed excess energy nucleus to shed excess energy

Radioactive decay series Radioactive decay series

U-

235, U

235, U-

238, and Th

238, and Th-

232 all decay to

232 all decay to stability via a series of radioactive isotopes stability via a series of radioactive isotopes

These include both alpha and beta

These include both alpha and beta emitters emitters

For example, U

For example, U-

238 decays to Pb

238 decays to Pb-

206 via

206 via 14 series nuclides, including Ra 14 series nuclides, including Ra-

226,

226, Rn Rn-

222, and Po

222, and Po-

210

210

Alpha decay/radiation Alpha decay/radiation

Alpha emitters are heavy atoms

Alpha particles are helium nuclei

Alpha particles are helium nuclei Can shield alphas with a piece of paper Can shield alphas with a piece of paper

Can shield alphas with a piece of paper

Alphas are very damaging to DNA

Alphas are emitted with a fixed energy

Example:

4 238 234 2 92 90

U Th

α

α ⎯⎯ → +

Beta decay/radiation Beta decay/radiation

All elements have at least one isotope that

All elements have at least one isotope that decays via beta emission decays via beta emission

Betas can have + or

Betas can have + or – charge charge Betas can have or Betas can have or charge charge

Betas are emitted with a range of energies

Betas are emitted with a range of energies

Positively

Positively-

charged betas (positrons) are

charged betas (positrons) are anti anti-

matter and also emit high

matter and also emit high-

energy

energy gamma radiation (2 x 511 keV photons) gamma radiation (2 x 511 keV photons)

Example:

Example: 234

234 90 91

Th Pa

β

−

⎯⎯ → +

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6

Electron capture Electron capture

Converts a proton into a neutron by

Converts a proton into a neutron by “capturing” an inner electron “capturing” an inner electron

Nucleus may emit a gamma ray or the

Nucleus may emit a gamma ray, or the

Nucleus may emit a gamma ray, or the nuclide produced may be radioactive nuclide produced may be radioactive

Example:

22 22 10 11 EC

Na Ne γ ⎯⎯ → +

Isomeric transition Isomeric transition

Following beta decay, the daughter

Following beta decay, the daughter nuclide will sometimes be in an excited nuclide will sometimes be in an excited (unstable) state, even if the atom is stable (unstable) state, even if the atom is stable ( ) , ( ) ,

The nucleus de

The nucleus de-

excites by emitting a

excites by emitting a photon photon

Example:

Example:

137 137 137 m IT

Cs Ba Ba

β

β γ

−

⎯⎯ → + ⎯⎯ → +

Internal conversion Internal conversion

Sometimes an excited nucleus will emit

Sometimes an excited nucleus will emit a photon that’s absorbed by an inner a photon that’s absorbed by an inner electron electron

This adds enough energy to eject the

This adds enough energy to eject the electron from the atom electron from the atom

The electrons will be emitted with a

The electrons will be emitted with a fixed energy fixed energy

Sometimes an x

Sometimes an x-

ray will also be emitted

ray will also be emitted

Spontaneous fission Spontaneous fission

Very large atomic nuclei are larger than

Very large atomic nuclei are larger than the range of the strong nuclear force the range of the strong nuclear force

These atoms sometimes break in two

These atoms sometimes break in two

These atoms sometimes break in two

These atoms sometimes break in two parts (fission) spontaneously parts (fission) spontaneously

This leaves two fission fragments,

This leaves two fission fragments, neutrons, and some gammas neutrons, and some gammas

Example:

Example:

137 238 99 55 92 37

2

SF

U Cs Rb n γ ⎯⎯ → + + +

Types of radiation and their Types of radiation and their properties properties

Radiation Radiation Type Type

Mass Mass Charge Charge Range Range QF QF Shield Shield Alpha Alpha 4 amu 4 amu +2 +2 <5 <5 μm 20 20 none none Beta Beta 0.0005 0.0005 +/ +/-

1

1 < 1cm < 1cm 1 1 Plastic Plastic Gamma Gamma WB WB 1 1 Lead Lead Neutron Neutron 1 WB WB 5 5-

20

20 hydrogen hydrogen

Bremsstrahlung Bremsstrahlung

X-
ray radiation emitted when beta

ray radiation emitted when beta particles pass an atom particles pass an atom

Heavy materials (such as lead) create

Heavy materials (such as lead) create y ( ) y ( ) more brems. radiation more brems. radiation

Best to use plastic to shield beta emitters

Best to use plastic to shield beta emitters

Some hunters in Georgia (nation) recently

Some hunters in Georgia (nation) recently died of bremsstrahlung radiation burns died of bremsstrahlung radiation burns

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7

Radiation dose and shielding Radiation dose and shielding calculations calculations Radiation dose Radiation dose

A measure of energy deposited in an

A measure of energy deposited in an absorber by ionizing radiation absorber by ionizing radiation

1 rad = 100 ergs/gram of absorber

1 rad = 100 ergs/gram of absorber

= 6.242x10

= 6.242x107 MeV/gm MeV/gm

1 Gray (Gy) = 1 Joule/kg

1 Gray (Gy) = 1 Joule/kg

=100 rads

Rem = rad x QF

Rem = rad x QF

Sievert (Sv) = Gy x QF

Sievert (Sv) = Gy x QF

Distance effects on radiation Distance effects on radiation dose dose

Dose rate drops off as the inverse square

f the distance to the source
f the distance to the source

So doubling your distance reduces dose

So doubling your distance reduces dose rate by a factor of 4 rate by a factor of 4

2 1 2 1 2 2

r DR DR r =

Example distance problem Example distance problem

50 meters 10 meters 5 rem/hr ? rem/hr

2

10 5 ? 5 0.2 50 25 m rem rem hr hr m ⎛ ⎞ = × = = ⎜ ⎟ ⎝ ⎠

Gamma Radiation Shielding Gamma Radiation Shielding

Used to reduce radiation dose to protect

Used to reduce radiation dose to protect personnel from over personnel from over-

exposure

exposure

Shielding equation:

Shielding equation: g q g q

x is the shield thickness

is the shield thickness

μ is the attenuation coefficient in units of

is the attenuation coefficient in units of cm cm2/gm /gm

x sh unsh

DR DR e μ

−

= ×

Buildup Buildup

In most real

In most real-

life cases, the radiation beam is

life cases, the radiation beam is broad, and some gammas will scatter within the broad, and some gammas will scatter within the shield back into the primary beam shield back into the primary beam

This is radiation that would not otherwise have

This is radiation that would not otherwise have caused radiation dose caused radiation dose caused radiation dose caused radiation dose

Buildup causes the radiation dose to be higher

Buildup causes the radiation dose to be higher than what would be calculated with just the than what would be calculated with just the shield shield

Buildup factors vary according to the gamma

Buildup factors vary according to the gamma energy and shield material energy and shield material – – you must use a you must use a reference to find them reference to find them

SLIDE 8

8

The full shielding equation The full shielding equation

x

DR B DR e μ

−

= × ×

sh unsh

DR B DR e μ = × ×

Sample problem Sample problem

3 meters DR = 15 rem/hr at 1 foot 6” Pb 3 meters at 1 foot μ= 0.02 cm2/gm ρ= 11.7 gm/cm3 6” = 15 cm What is the dose rate to the worker?

Use distance and shielding Use distance and shielding

2 2

30 15 / 0.15 / 300 cm DR rem hr rem hr cm ⎛ ⎞ = × = ⎜ ⎟ ⎝ ⎠

( )

2 3

.0 2 1 1 .7 1 5

1 5 / 4 .4 8 /

g m c m c m g m c m sh

D R m rem h r e m re m h r

− × ×

= × = Design a shield to reduce dose to Design a shield to reduce dose to 100 mrem/hr 100 mrem/hr

1 meter DR = 15 rem/hr

? cm

1 meter μ= 0.02 cm2/gm ρ= 11.7 gm/cm3 6” = 15 cm

Solve equation for x and solve Solve equation for x and solve numerically: numerically:

2 1

0.1 / ln ln 15 / DR rem hr DR rem hr x ⎛ ⎞ ⎛ ⎞ ⎜ ⎟ ⎜ ⎟ ⎝ ⎠ ⎝ ⎠

( )

2 3

0.02 / 11.7 / 21.4 8.45 x cm gm gm cm cm in μρ ⎝ ⎠ ⎝ ⎠ = = − − × = =

Using the gamma constant Using the gamma constant

Every gamma

Every gamma-

emitting isotope will have

emitting isotope will have an associated gamma constant (which can an associated gamma constant (which can be referenced) be referenced)

DR=

DR=ΓA at one meter where A at one meter where Γ Γ is the is the gamma constant in units of r/hr per Ci at a gamma constant in units of r/hr per Ci at a distance of 1 meter (or equivalent SI distance of 1 meter (or equivalent SI units) units)

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9

Gamma constant example Gamma constant example

ΓCo Co-

60

60 = 1.33 r/hr per Ci at 1 meter

= 1.33 r/hr per Ci at 1 meter

So a 1000 Ci source will give a dose rate

f 1330 r/hr at 1 meter, or about 330 r/hr
f 1330 r/hr at 1 meter, or about 330 r/hr

, at 2 meters at 2 meters

ΓCs Cs-

137

137 = 0.332 r/hr per Ci at 1 meter

= 0.332 r/hr per Ci at 1 meter

So

So – – calculate the dose rate from a 500 Ci calculate the dose rate from a 500 Ci Cs Cs-

137 source that is 2 meters away

137 source that is 2 meters away

Interactions of photons with matter Interactions of photons with matter

Photo

Photo-

electric effect

electric effect

Photon absorbed by electron, knocks electron

Photon absorbed by electron, knocks electron from atom from atom

Compton scattering

Compton scattering

Compton scattering

Compton scattering

Photon absorbed by electron, re

Photon absorbed by electron, re-

emitted with

emitted with lower energy in random direction lower energy in random direction

Pair production

Pair production

High

High-

energy photon spontaneously forms

energy photon spontaneously forms electron/positron pair when passing near electron/positron pair when passing near atomic nucleus atomic nucleus

Photo-electric effect Pair production Compton Atomic # Photon energy p scattering 1.022 MeV A

Some sample problems Some sample problems Sample problem Sample problem

Calculate radiation dose to a person spending 2

Calculate radiation dose to a person spending 2 hours at a distance of 5 meters from a 1500 Ci hours at a distance of 5 meters from a 1500 Ci Co Co-

60 source.

60 source.

Γ = 1 33 r/hr per Ci at 1 meter

= 1 33 r/hr per Ci at 1 meter

Γ = 1.33 r/hr per Ci at 1 meter

= 1.33 r/hr per Ci at 1 meter

What stay time would you give a person at this

What stay time would you give a person at this distance? distance?

Now calculate the radiation dose from this

Now calculate the radiation dose from this source in 33 years source in 33 years

T1/2 1/2 = 5.27 yrs

= 5.27 yrs

Same source…. Same source….

What is the radiation dose rate at 1 meter

What is the radiation dose rate at 1 meter from this source (when new) with 4 inches from this source (when new) with 4 inches

f lead shielding?
f lead shielding?

g g

2 inches of lead will reduce dose rate by a

2 inches of lead will reduce dose rate by a factor of 10 for Co factor of 10 for Co-

60

60

SLIDE 10

10

Contamination surveys Contamination surveys

You are counting a C

You are counting a C-

14 sample with a GM

14 sample with a GM pancake probe. The count rate is about 100,000 pancake probe. The count rate is about 100,000 cpm and counting efficiency is 5%. How many cpm and counting efficiency is 5%. How many micro micro-Curies of activity do you have? Curies of activity do you have? micro micro Curies of activity do you have? Curies of activity do you have?

1

1 μCi = 2.22 million dpm Ci = 2.22 million dpm

How many cpm do you expect from the same

How many cpm do you expect from the same activity in a P activity in a P-

32 source?

32 source?

Counting efficiency = 35%

How many cpm do you expect with an NaI

How many cpm do you expect with an NaI probe? probe?

Background radiation Background radiation Sources Sources

Radon

Radon – – 200 mrem/yr 200 mrem/yr

Rocks and soils

Rocks and soils – – 28 mrem/yr 28 mrem/yr

Biochemistry

Biochemistry – – 40 mrem/yr 40 mrem/yr

Cosmic radiation

Cosmic radiation – – 27 mrem/yr 27 mrem/yr

Medical procedures

Medical procedures – – 53 mrem/yr 53 mrem/yr

Consumer products

Consumer products – – 10 mrem/yr 10 mrem/yr

Other

Other – – 2 mrem/yr 2 mrem/yr

Total

Total – – 360 mrem/ yr (average) 360 mrem/ yr (average)

Variations Variations

Cosmic radiation dose is higher at high

Cosmic radiation dose is higher at high elevations and near the poles elevations and near the poles

Dose from geology and radon are higher

Dose from geology and radon are higher

Dose from geology and radon are higher

Dose from geology and radon are higher in areas with more igneous rocks, coals, in areas with more igneous rocks, coals, and black shales at the surface and black shales at the surface

Can’t change dose from biochemistry

Can’t change dose from biochemistry

Background radiation levels are up to 25

Background radiation levels are up to 25 rem/yr (Ramsar, Iran) rem/yr (Ramsar, Iran)

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11

Biological effects of radiation Biological effects of radiation exposure exposure Interactions in the cell Interactions in the cell

Radiation causes ionizations in the cell

Radiation causes ionizations in the cell

These can create free radicals that attack

These can create free radicals that attack DNA, causing many kinds of damage DNA, causing many kinds of damage

Some of this damage can be carginogenic

Some of this damage can be carginogenic

Some of this damage can be carginogenic

Some of this damage can be carginogenic

In addition, radiation can directly cause

In addition, radiation can directly cause single single-

or double
r double-
stranded DNA breaks

stranded DNA breaks

However, radiation is considered a weak

However, radiation is considered a weak carcinogen carcinogen

Cellular response Cellular response

Cells are capable of repairing DNA damage

Cells are capable of repairing DNA damage from radiation and other mutagens from radiation and other mutagens

A mutation only occurs if DNA damage is

A mutation only occurs if DNA damage is passed on to a “daughter” cell passed on to a “daughter” cell

Cells that repair damage correctly or that

Cells that repair damage correctly or that die do not cause mutations die do not cause mutations

DNA damage repair DNA damage repair

Three options:

Three options:

Damage is properly repaired (no mutation)

Damage is not repaired properly (or not

Damage is not repaired properly (or not repaired) and cell dies (no mutation) repaired) and cell dies (no mutation)

Damage is not repaired properly and cell does

Damage is not repaired properly and cell does not die (mutation) not die (mutation)

Mutations can be: Mutations can be:

Harmful

Harmful – – birth defects, cancer, etc. birth defects, cancer, etc.

Beneficial

Beneficial – – evolution evolution Neutral Neutral most common most common

Neutral

Neutral – most common most common

Much of genome seems to be non

Much of genome seems to be non-

coding

coding

Not all genes are active in any given cell

Many bases can be changed slightly without

Many bases can be changed slightly without changing the amino acid or protein changing the amino acid or protein

Factors affecting cells’ radiation Factors affecting cells’ radiation sensitivity sensitivity

These factors make a cell

These factors make a cell more more sensitive sensitive to radiation to radiation

Less

Less specialized specialized Less Less specialized specialized

Faster

Faster rate of division rate of division

Longer

Longer reproductive lifetime reproductive lifetime

Higher

Higher level of oxygen level of oxygen

SLIDE 12

12

Two types of radiation exposure Two types of radiation exposure

Acute radiation exposure is exposure to

Acute radiation exposure is exposure to high levels of radiation in a short period of high levels of radiation in a short period of time time

Typical of radiation accident victims

Chronic exposure is exposure to low levels

f radiation for prolonged periods of time
f radiation for prolonged periods of time

Typical of radiation workers and HBRA

Typical of radiation workers and HBRA inhabitants inhabitants

Acute whole Acute whole-

body exposure

body exposure

~1 rem

~1 rem – – chromosomal damage chromosomal damage

~25 rem

~25 rem – – changes in blood cell counts changes in blood cell counts

~100 rem

~100 rem – – radiation sickness radiation sickness

~450 rem

~450 rem – LD LD

~450 rem

~450 rem – LD LD50

50 ~1000 rem

~1000 rem – – LD LD100

100 At higher levels of exposure, see some syndromes

At higher levels of exposure, see some syndromes

GI, CNS, hematopoetic, etc.

High exposure to parts of body may not result in

High exposure to parts of body may not result in death of patient (e.g. cancer therapy, XRD, etc) death of patient (e.g. cancer therapy, XRD, etc)

Chronic exposure Chronic exposure

Less well

Less well-

defined

defined

Most regulations based on Linear, No

Most regulations based on Linear, No-

Threshold (LNT) hypothesis that all

Threshold (LNT) hypothesis that all radiation above background is potentially radiation above background is potentially g p y g p y harmful and risk is proportional to dose harmful and risk is proportional to dose

However, there is some evidence that

However, there is some evidence that there is a threshold, below which radiation there is a threshold, below which radiation is either harmless or beneficial (hormesis) is either harmless or beneficial (hormesis)

Subject of much study and debate for

Subject of much study and debate for many years many years

Cancer risk

LNT S li

Radiation dose

Hormesis Threshold Supra-linear Linear quadratic

Studies show: Studies show:

Residents of HBRA are not affected by

Residents of HBRA are not affected by high natural radiation levels high natural radiation levels

Radiologists are not affected by

Radiologists are not affected by

ccupational radiation exposure
ccupational radiation exposure
ccupational radiation exposure
ccupational radiation exposure
Nuclear workers are not affected by

Nuclear workers are not affected by

ccupational radiation exposure
ccupational radiation exposure
Some Hiroshima, Nagasaki, and Chernobyl

Some Hiroshima, Nagasaki, and Chernobyl survivors show no increase (in some cases survivors show no increase (in some cases a small drop) in cancer rates a small drop) in cancer rates

SLIDE 13

13

Risks Risks

Using LNT, the risk of getting cancer from

Using LNT, the risk of getting cancer from exposure to 100 exposure to 100-

200 mrem/yr above

200 mrem/yr above background is about 1 in 10,000 background is about 1 in 10,000 g , g ,

Risk of dying in an auto accident is about

Risk of dying in an auto accident is about 1 in 7,000 each year (about 1 in 100 over 1 in 7,000 each year (about 1 in 100 over a lifetime) a lifetime)

Background cancer risk is about 16 in 100

HPS and ICRP HPS and ICRP

HPS advises against calculating risk for

HPS advises against calculating risk for any exposures of less than 10 rem any exposures of less than 10 rem because of high uncertainties in numbers because of high uncertainties in numbers g g

ICRP recommends against calculating

ICRP recommends against calculating cancer deaths in a population when most cancer deaths in a population when most-

exposed individual receives a very small

exposed individual receives a very small dose dose

Recommendations on Recommendations on terminating pregnancy terminating pregnancy

F etal age <5 rad 5-15 rad >15 rad <2 wks No No No 2-8 wks No

If other se severe risks If other

risks 8-15 wks No If other risks Highest risk to fetus >15 wks No No No

Inside an x Inside an x-

ray tube

ray tube

filament electrons X b +

Electron (-)

Bremsstrahlung X-ray beam

Filtration Filtration

Bremsstralung x

Bremsstralung x-

rays are emitted with a range

rays are emitted with a range

f energies, ranging from nearly 0 keV to the
f energies, ranging from nearly 0 keV to the

maximum maximum

Low

Low-

energy x

energy x-

rays do not penetrate the body,

rays do not penetrate the body, gy gy y p y, y p y, so they do not contribute to forming an x so they do not contribute to forming an x-

ray

ray image image – – they only give radiation dose to the they only give radiation dose to the patient patient

We use aluminum or copper filters to shield, or

We use aluminum or copper filters to shield, or filter out the low filter out the low-

energy x

energy x-

rays

rays

This “hardens” the beam to make it more

This “hardens” the beam to make it more penetrating and to reduce radiation dose to the penetrating and to reduce radiation dose to the patient patient

X-

ray energy distribution

ray energy distribution

# of photons Less penetrating at lower energy The filter eliminates lowest-energy x-rays X-ray photon energy More penetrating at higher energy

SLIDE 14

14 Machine parameters (technique) Machine parameters (technique)

kVp is the voltage used to accelerate the

kVp is the voltage used to accelerate the electrons electrons

Higher kVp means a higher x

Higher kVp means a higher x-

ray energy

ray energy (“h d ” b ) d d di i d (“h d ” b ) d d di i d (“harder” beam), and reduces radiation dose (“harder” beam), and reduces radiation dose

mA is a measure of the beam current

mA is a measure of the beam current – – the number of electrons hitting the target the number of electrons hitting the target

Higher mA means that more electrons are

Higher mA means that more electrons are emitted, and more x emitted, and more x-

ray photons are emitted,

ray photons are emitted, so higher mA means a stronger x so higher mA means a stronger x-

ray beam

ray beam and higher radiation dose rate and higher radiation dose rate

Radiation detectors and Radiation detectors and personnel monitoring devices personnel monitoring devices Types of detectors Types of detectors

Gas

Gas-

filled detectors

filled detectors

Geiger

Geiger-

Müeller (GM) tubes

Müeller (GM) tubes

Ion chambers

Proportional counters

Scintillation

Scintillation-

type detectors

type detectors

Sodium

Sodium-

iodide (NaI) crystals

iodide (NaI) crystals

Zinc sulfide (ZnS) crystals

Liquid scintillation counters

Pulse height versus voltage Pulse height versus voltage GM tubes GM tubes

Apply high voltage to gas

Apply high voltage to gas

Radiation causes complete ionization of gas,

Radiation causes complete ionization of gas, giving a count on the meter giving a count on the meter g g g g

There is short “dead time” after each count,

There is short “dead time” after each count, so tube can saturate so tube can saturate

Three types of probe

Three types of probe – – “pancake”, “hot “pancake”, “hot dog”, and energy dog”, and energy-

compensated

compensated

Used for contamination and radiation

Used for contamination and radiation surveys surveys

SLIDE 15

15

GM limitations GM limitations

Not energy

Not energy-

sensitive (except for energy

sensitive (except for energy-

compensated GM)

compensated GM)

Dead time means that very high count

Dead time means that very high count rates can saturate tube rates can saturate tube

Not sensitive to low

Not sensitive to low-

energy betas and

energy betas and gammas gammas

GM benefits GM benefits

Relatively simple and inexpensive

Relatively simple and inexpensive

Relatively rugged

Relatively rugged Relatively constant counting efficiency Relatively constant counting efficiency

Relatively constant counting efficiency

Relatively constant counting efficiency across a variety of radiation energies across a variety of radiation energies

GM uses GM uses

Pancake probe very good for

Pancake probe very good for contamination surveys contamination surveys

Hot dog probe useful for radiation

Hot dog probe useful for radiation surveys, provided properly calibrated surveys, provided properly calibrated

Energy

Energy-

compensated GM good for

compensated GM good for radiation level surveys radiation level surveys

Energy Energy-

dependence effect

dependence effect

Ion chambers Ion chambers

Radiation causes ionizations in chamber

Ionizations create electrical current, and

Ionizations create electrical current, and strength of current is related to radiation strength of current is related to radiation dose rate dose rate dose rate dose rate

Used to measure radiation levels

Sensitivity does not depend on radiation

Sensitivity does not depend on radiation energy energy

Pressurized ion chamber more sensitive

Pressurized ion chamber more sensitive and respond faster, but can develop leaks and respond faster, but can develop leaks

Ion chamber pressure and Ion chamber pressure and temperature correction factor temperature correction factor

SLIDE 16

16

Proportional counters Proportional counters

Radiation interactions cause spike in

Radiation interactions cause spike in voltage reading voltage reading

Size of spike is

Size of spike is proportional proportional to radiation to radiation p p p p p energy energy

Since

Since α particles are more energetic than particles are more energetic than betas, can use same detector to count betas, can use same detector to count and and β radiation radiation simultaneously simultaneously

However, need constant flow of gas

However, need constant flow of gas (propane) to function properly (propane) to function properly

Some proportional counters Some proportional counters NaI scintillation detectors NaI scintillation detectors

Crystal emits photons during interactions with

Crystal emits photons during interactions with gamma rays gamma rays

Photons travel to photo

Photons travel to photo-

multiplier tube, which

multiplier tube, which amplifies signal amplifies signal amplifies signal amplifies signal

Sensitive to gamma radiation

Used for contamination and radiation surveys for

Used for contamination and radiation surveys for gamma emitters gamma emitters

Also used for nuclide ID (when used with multi

Also used for nuclide ID (when used with multi-

channel analyzer)

channel analyzer)

NaI detector sizes NaI detector sizes

Thin

Thin-

crystal (1” x 1mm)

crystal (1” x 1mm) – – used for low used for low-

energy gammas (10

energy gammas (10-

100 keV)

100 keV)

Thick

Thick-

crystal (1”x1”)

crystal (1”x1”) – – used for high used for high-

energy gammas (100+ keV)

energy gammas (100+ keV)

Thicker crystals available (2”x2”, 3”x3”,

Thicker crystals available (2”x2”, 3”x3”, and larger sizes) and larger sizes)

Background counts increase as crystal size

Background counts increase as crystal size increases increases – – up to 14,000 cpm for a 3”x3”) up to 14,000 cpm for a 3”x3”)

NaI limitations NaI limitations

Not sensitive to alpha or beta radiation

Not sensitive to alpha or beta radiation

Often have low efficiency

Often have low efficiency Usually have higher background counts Usually have higher background counts

Usually have higher background counts

Usually have higher background counts than GM tubes (harder to detect low levels than GM tubes (harder to detect low levels

f contamination)
f contamination)
Crystals are fragile and thermally sensitive

Crystals are fragile and thermally sensitive

SLIDE 17

17

NaI benefits NaI benefits

Can have very large crystals to increase

Can have very large crystals to increase sensitivity sensitivity

Can be used to identify isotopes by

Can be used to identify isotopes by looking for a specific gamma energy looking for a specific gamma energy

Can be used to measure radiation levels

Can be used to measure radiation levels because # photons is proportional to because # photons is proportional to gamma energy gamma energy

NaI uses NaI uses

Nuclide ID and gamma spectroscopy

Nuclide ID and gamma spectroscopy

Radiation levels (usually as part of a

Radiation levels (usually as part of a micro micro-R meter) R meter) micro micro R meter) R meter)

Gamma contamination measurements

Gamma contamination measurements

Can be used to measure beta emitters via

Can be used to measure beta emitters via bremsstrahlung emitted from betas bremsstrahlung emitted from betas interacting in crystal, but not reliable interacting in crystal, but not reliable

Ideal Ideal versus versus actual actual actual actual gamma gamma spectrum spectrum

Gamma spec features Gamma spec features

X-
ray peaks at around 100 keV. These are generated by photoelectric

ray peaks at around 100 keV. These are generated by photoelectric absorption within the material surrounding the crystal. absorption within the material surrounding the crystal.

Backscatter peaks at around 250 keV. These are a result of the backward

Backscatter peaks at around 250 keV. These are a result of the backward scattering of rays from outside of the detector. scattering of rays from outside of the detector.

An annihilation peak at 511 keV, from the detection of an annihilation photon

An annihilation peak at 511 keV, from the detection of an annihilation photon from pair production outside the Ge crystal. from pair production outside the Ge crystal.

Single and double escape peaks at energies of 511 keV and 1022 keV below

Single and double escape peaks at energies of 511 keV and 1022 keV below the photopeak energy. At energies greater than twice the rest mass of the the photopeak energy. At energies greater than twice the rest mass of the electron (1.022 MeV), pair production is a possibility. The positron may then electron (1.022 MeV), pair production is a possibility. The positron may then recombine with an electron and decay back to two 511keV rays which may be recombine with an electron and decay back to two 511keV rays which may be recombine with an electron and decay back to two 511keV rays which may be recombine with an electron and decay back to two 511keV rays which may be detected in the annihilation peak, but if one or more of these escape from the detected in the annihilation peak, but if one or more of these escape from the detector without any further interactions the escape peaks will be detected at detector without any further interactions the escape peaks will be detected at energies of energies of -

511 keV and

511 keV and -

1022 keV.

1022 keV.

The Compton edge and Compton continuum are caused by Compton

The Compton edge and Compton continuum are caused by Compton

scattering. The Compton edge corresponds to a maximum energy transfer
scattering. The Compton edge corresponds to a maximum energy transfer

when when θ = 180. The continuum arises from all other scattering angles. = 180. The continuum arises from all other scattering angles.

The Co photopeaks at 1173 and 1333 keV, correspond to all of the

The Co photopeaks at 1173 and 1333 keV, correspond to all of the γ-ray ray energy from the interaction being deposited in the detector. energy from the interaction being deposited in the detector.

The photopeaks are of most interest. To

The photopeaks are of most interest. To -

ray spectroscopists, the majority of

ray spectroscopists, the majority of interest lies in the region 0.2 interest lies in the region 0.2 -

2 MeV, and so the need to reduce the other

2 MeV, and so the need to reduce the other features becomes a priority. features becomes a priority.

ZnS crystals ZnS crystals

Only used to measure alpha radiation

Crystals are sensitive to shock

Crystals are sensitive to shock Efficiency is typically low Efficiency is typically low

Efficiency is typically low

Some alpha detectors Some alpha detectors

SLIDE 18

18

Liquid scintillation counters Liquid scintillation counters

Used to count

Used to count β emitters emitters

Sensitive to very wide range of beta

Sensitive to very wide range of beta energies energies g

Can be self

Can be self-

correcting for counting

correcting for counting efficiencies (give DPM readout) efficiencies (give DPM readout)

Can be tricked by static electricity and

Can be tricked by static electricity and chemical luminescence chemical luminescence

Can be expensive ($40 K or more)

Other detectors Other detectors

Neutron detectors (fast and thermal

Neutron detectors (fast and thermal neutrons) neutrons)

HPGe gamma spectroscopy units

HPGe gamma spectroscopy units

Alpha spectroscopy (multiple types)

Alpha spectroscopy (multiple types)

Alpha spectroscopy (multiple types)

Alpha spectroscopy (multiple types)

Radon detectors

Radon detectors

High

High-

pressure pressurized ion chambers

pressure pressurized ion chambers (up to 25 atmospheres) (up to 25 atmospheres)

Whole

Whole-

body counters

body counters

More….

More….

Counting geometry Counting geometry

Proportional counters can give

Proportional counters can give nearly nearly 4 4 π geometry geometry

“4

“4 π” means that the sample is ” means that the sample is p completely surrounded by the completely surrounded by the counting medium counting medium

Comes from the surface area of a

Comes from the surface area of a sphere, which is equal to 4 sphere, which is equal to 4 π steradians steradians

Counting on a flat surface is 2

Counting on a flat surface is 2 π geometry geometry

When selecting instruments for When selecting instruments for response to an incident: response to an incident:

Choose appropriate detectors for expected

Choose appropriate detectors for expected types of radiation types of radiation

Take at least 1 backup instrument

Take at least 1 backup instrument

Take at least 1 backup instrument

Take at least 1 backup instrument

If situation is unknown, take GM, NaI, and

If situation is unknown, take GM, NaI, and ion chamber or micro ion chamber or micro-

R meter

R meter

Statistics Statistics

Not very exciting, but important Not very exciting, but important anyhow anyhow

Basic terms Basic terms

Mean

Mean

Mode

Mode Median Median

Median

Median

Standard Deviation

Standard Deviation

Confidence Levels

Confidence Levels

SLIDE 19

19

Mean, median, and mode Mean, median, and mode

Mean

Mean -

the arithmetic average of a

the arithmetic average of a collection of measurements. collection of measurements.

Mode

Mode -

the most likely value in a set

the most likely value in a set y

f measurements.
f measurements.

Median

Median -

the center value in a set of

the center value in a set of measurements. measurements.

In a “normal” distribution, these are

In a “normal” distribution, these are the same value the same value

Gaussian (“normal”) distribution Gaussian (“normal”) distribution

Centered around the

Centered around the mean mean

Area beneath curve is

Area beneath curve is equal to 1 equal to 1

Asymptotically

Asymptotically y p y y p y approaches X approaches X-

axis

axis

The goal of statistics (in

The goal of statistics (in D&D, for example) is to D&D, for example) is to decide if a given high decide if a given high count count-

rate point is actual

rate point is actual contamination, or just a contamination, or just a high outlier in the high outlier in the background distribution background distribution

Some more terminology Some more terminology

Accuracy

Accuracy – – how close is the data to how close is the data to the “true” value? the “true” value?

Precision

Precision – how closely clustered are how closely clustered are

Precision

Precision how closely clustered are how closely clustered are individual measurements? individual measurements?

Uncertainty

Uncertainty – – how much do the data how much do the data vary from the “true” value. vary from the “true” value.

Accuracy versus precision Accuracy versus precision

Accuracy

Precision

Sampling a population Sampling a population

Statistical methods attempt to infer

Statistical methods attempt to infer information about an entire population information about an entire population from a sample of that population from a sample of that population

Population

Population -

the entire group of possible

the entire group of possible measurements measurements -

population parameters are

population parameters are the true values. the true values.

Sample

Sample -

a small group of the population

a small group of the population -

sample parameters are the estimate of the

sample parameters are the estimate of the true value made from the sample results. true value made from the sample results.

Standard deviation Standard deviation

Standard Deviation

Standard Deviation – – a measure of the a measure of the variability in the data. variability in the data.

Mathematically noted as multiples of

Mathematically noted as multiples of

68% of members of a population fall within

68% of members of a population fall within

68% of members of a population fall within the 1 the 1 error bars error bars

95% fall within the 2

95% fall within the 2 error bars error bars

99% fall within the 3

99% fall within the 3 error bars error bars

So, if a paper reports results to the 95%

So, if a paper reports results to the 95% confidence interval, they are reporting confidence interval, they are reporting results to the 2 results to the 2 level level

SLIDE 20

20

Case study #1 Case study #1

In a remediation plan, one licensee

In a remediation plan, one licensee claimed a pile of soil was well claimed a pile of soil was well-

characterized and could be released for

characterized and could be released for di l di l disposal disposal

The release limit was 35 pCi/g

Ave. contamination levels were 33 pCi/g
Ave. contamination levels were 33 pCi/g

Standard deviation was 34.5 pCi/g

Should the licensee’s claim be believed?

Case study #2 Case study #2

A licensee’s I

A licensee’s I-

131 emissions suddenly

131 emissions suddenly skyrocketed, leading to cessation of I skyrocketed, leading to cessation of I-

131 use

131 use for several months. However, 3 months after for several months. However, 3 months after use stopped, I use stopped, I-

131 was still counted in the

131 was still counted in the sample filters. sample filters. p

The reason for this is that, with 1

The reason for this is that, with 1-

minute sample

minute sample and background counts, random fluctuations in and background counts, random fluctuations in background showed up as “real” counts and, background showed up as “real” counts and, subsequently, as discharges subsequently, as discharges

Solution was to increase counting times and to

Solution was to increase counting times and to use a single use a single-

channel analyzer to reduce

channel analyzer to reduce background counts in energy regions of interest background counts in energy regions of interest

Case study #2 data Case study #2 data

trial counts trial counts count rate 1 407 1 4365 437 2 432 2 4492 449 3 407 3 4449 445 4 414 4 4581 458 5 428 5 4362 436 6 431 6 4417 442 7 469 7 4370 437 I minute background 10 minute background 8 448 8 4263 426 9 423 9 4332 433 10 452 10 4364 436 11 426 Descriptive statistics Descriptive statistics Mean 430.6364 Mean 439.95 Median 428 Median 436.75 Mode 407 Mode #N/A Standard Deviation 19.26797 Standard Deviation 8.954856 Sample Variance 371.2545 Sample Variance 80.18944 Confidence Level(95.0%) 12.9444 Confidence Level(95.0%) 6.405923

Control charts Control charts

Used to identify instrument trends, even before

Used to identify instrument trends, even before an instrument goes “out of specification” an instrument goes “out of specification”

Obtain a number of sample counts for a source

Obtain a number of sample counts for a source and background and background and background. and background.

Determine the mean and standard deviation of

Determine the mean and standard deviation of both sets of data. both sets of data.

Plot daily or weekly checks against mean and

Plot daily or weekly checks against mean and pre pre-

determined error bars and examine for

determined error bars and examine for trends trends

Expected response Expected response – – variations variations around the mean around the mean

Alpha Background Control Chart

0 15 0.20 0.25 0.30 ate (cpm)

0.10
0.05

0.00 0.05 0.10 0.15 6/8/2001 6/13/2001 6/18/2001 6/23/2001 6/28/2001 7/3/2001 7/8/2001 7/13/2001 7/18/2001 Date Alpha Background Count Ra Alpha Background

2 Sigma

+2 Sigma Average

Possible problem Possible problem – – dropping dropping trend in beta readings trend in beta readings

Beta Source Response Control Chart

4200 4300 4400 4500 (cpm) 3500 3600 3700 3800 3900 4000 4100 6/8/2001 6/13/2001 6/18/2001 6/23/2001 6/28/2001 7/3/2001 7/8/2001 7/13/2001 7/18/2001 Date Beta Source Response ( Beta Response +10%

10%

Average

SLIDE 21

21

Dosimetry Dosimetry Types of dosimetry Types of dosimetry

Film badge

Film badge

Thermo

Thermo-

luminescent dosimeters (TLD)

luminescent dosimeters (TLD) Optically Optically stimulated dosimeters (OSL) stimulated dosimeters (OSL)

Optically

Optically-stimulated dosimeters (OSL) stimulated dosimeters (OSL)

Neutron badges (various types)

Neutron badges (various types)

Electronic dosimeters

Electronic dosimeters

Self

Self-

reading dosimeters (usually not used

reading dosimeters (usually not used as dosimeter as dosimeter-

of
f-
record)

record)

Film badge Film badge

Radiation exposes film, so higher dose

Radiation exposes film, so higher dose gives darker film gives darker film

Inexpensive simple cheap

Inexpensive, simple, cheap

Oldest dosimetry technology

Can be read multiple times

However, can be sensitive to environment

Lowest reading about 10 mrem

TLD TLD

Radiation exposure causes electrons to

Radiation exposure causes electrons to jump to higher stable energy level jump to higher stable energy level

Heating crystal releases e

Heating crystal releases e- photon emitted photon emitted

Heating crystal releases e

Heating crystal releases e , photon emitted , photon emitted

Rugged, accurate, mature technology

Rugged, accurate, mature technology

Sensitive to wide range of energies

Sensitive to wide range of energies

Crystals can crack, can only be read once

Crystals can crack, can only be read once

Lowest reading about 10 mrem

Lowest reading about 10 mrem

OSL OSL

Dose read by scanning with laser beam

Dose read by scanning with laser beam instead of heating instead of heating

Rugged sensitive can be re

Rugged sensitive can be re-read read

Rugged, sensitive, can be re

Rugged, sensitive, can be re read read

More expensive than other badges

Sensitivity and performance sometimes

Sensitivity and performance sometimes erratic (personal observation) erratic (personal observation)

Only offered by Landauer

Neutron Neutron

Variety of types

Variety of types

Most are only sensitive to high OR low

Most are only sensitive to high OR low-

energy neutrons not both

energy neutrons not both energy neutrons, not both energy neutrons, not both

Need to know neutron energies in order to

Need to know neutron energies in order to use correct badge use correct badge

Neutrons are hard to measure!

Neutrons are hard to measure!

SLIDE 22

22

Electronic dosimeters Electronic dosimeters

Many designs

Can be used in specific situations (e.g.

Can be used in specific situations (e.g. entry into high radiation areas) entry into high radiation areas) y g ) y g )

Can also be used (sometimes) as

Can also be used (sometimes) as dosimeter dosimeter-

of
f-
record

record

Can have interference from outside

Can have interference from outside electrical signals electrical signals

Usually rugged and reliable

Continuing to evolve at a rapid rate

Pocket ion chambers Pocket ion chambers (also called self (also called self-

reading, or “pen”

reading, or “pen” dosimeters) dosimeters)

Usually used only for entry into high

Usually used only for entry into high radiation areas radiation areas ll d l f k f ll d l f k f

Usually used only for worker information

Usually used only for worker information

Some recent models can be used as

Some recent models can be used as dosimeter dosimeter-

of
f-
record

record

Dosimeter regulations Dosimeter regulations

Required for anyone expected to receive

Required for anyone expected to receive more than 125 mrem in a calendar quarter more than 125 mrem in a calendar quarter

Required for anyone entering a radiation

Required for anyone entering a radiation area or high radiation area area or high radiation area area or high radiation area area or high radiation area

In some cases, multiple dosimetry is

In some cases, multiple dosimetry is required required

Ring badges for people handling isotopes

Arm, collar, fetal, and other specialty badges

Arm, collar, fetal, and other specialty badges as appropriate as appropriate

Importance of dose records Importance of dose records

The single most important document to

The single most important document to protect your company in the event of a protect your company in the event of a radiation injury lawsuit is a set of radiation injury lawsuit is a set of dosimetry records showing that the dosimetry records showing that the dosimetry records showing that the dosimetry records showing that the worker did not exceed radiation exposure worker did not exceed radiation exposure limits while working for your company limits while working for your company

Dose records must be retained for 30 years after

Dose records must be retained for 30 years after an employee leaves an employee leaves

May be asked to supply dose records to new

May be asked to supply dose records to new employers for a departing employee employers for a departing employee

Air sampling Air sampling Why perform air sampling? Why perform air sampling?

Measure environmental releases

Measure environmental releases

Measure breathing zone airborne nuclide

Measure breathing zone airborne nuclide concentrations concentrations concentrations concentrations

Measure results of accidental release

Measure results of accidental release

Routine environmental monitoring (inside

Routine environmental monitoring (inside and outside facility) and outside facility)

SLIDE 23

23

Typical setup Typical setup

Sample point

Sample lines

Sample lines Filter Filter

Filter

Pump

Sample point Sample point

Should be towards the center of the

Should be towards the center of the airflow, in the air to be sampled airflow, in the air to be sampled

i.e. downstream of exhaust filter for

i.e. downstream of exhaust filter for i.e. downstream of exhaust filter for i.e. downstream of exhaust filter for environmental sampling environmental sampling

Should be in a straight section of duct

Should be in a straight section of duct

Sample lines Sample lines

Should be as straight as possible and

Should be as straight as possible and bends should be large radius bends should be large radius

Should be as short as possible

Should be as short as possible p

Should slope downhill from sample

Should slope downhill from sample point to filter if possible point to filter if possible

Should be material that will not react

Should be material that will not react chemically with isotopes chemically with isotopes

Should be smooth and warm enough

Should be smooth and warm enough to keep volatile nuclides from to keep volatile nuclides from condensing condensing

Filter Filter

Should be suitable to capture isotopes of

Should be suitable to capture isotopes of interest interest

Must be able to collect for entire sampling

Must be able to collect for entire sampling

Must be able to collect for entire sampling

Must be able to collect for entire sampling period (e.g. one week) without saturating period (e.g. one week) without saturating

r releasing materials
r releasing materials
Should be able to be removed and

Should be able to be removed and counted easily and efficiently counted easily and efficiently

Sample pump Sample pump

Must be reliable

Must be reliable – – sample times may be as sample times may be as much as several months much as several months

Must draw enough air to maintain

Must draw enough air to maintain isokinetic sampling conditions isokinetic sampling conditions

Isokinetic sampling Isokinetic sampling

Ideally, the flow velocity in the sample

Ideally, the flow velocity in the sample tube should be equal to the flow velocity tube should be equal to the flow velocity in the exhaust stream in the exhaust stream

Different flow rates can lead to over

Different flow rates can lead to over-

or
r

under under-

representing various particle sizes

representing various particle sizes

Ex: faster flow rate in sample tube can skew

Ex: faster flow rate in sample tube can skew results towards larger particles results towards larger particles

SLIDE 24

24

Isokinetic sampling equations Isokinetic sampling equations

2

Flowrate Velocity r π =

2 2 stack sample iso stack

FR r Flowrate r × = A little on bioassays A little on bioassays Bioassay programs Bioassay programs

Required to perform bioassay whenever

Required to perform bioassay whenever there is an uptake, a potential uptake, or there is an uptake, a potential uptake, or when isotope use meets certain criteria when isotope use meets certain criteria

These criteria are specified in NUREG 8.9

These criteria are specified in NUREG 8.9 and NUREG 4884 and ANSI standards and NUREG 4884 and ANSI standards

Examples

Examples – – your policy may call for your policy may call for bioassay following use of 1 mCi of I bioassay following use of 1 mCi of I-

131

131

r I
r I-
125, 40 mCi of H

125, 40 mCi of H-

3, or 20 mCi of C

3, or 20 mCi of C-

14

14

r S
r S-
35

35

Uses for bioassay Uses for bioassay

Confirm (or reject) uptake of radioactive

Confirm (or reject) uptake of radioactive materials materials

Quantify uptake for subsequent internal

Quantify uptake for subsequent internal

Quantify uptake for subsequent internal

Quantify uptake for subsequent internal dosimetry dosimetry

Track progress of elimination either

Track progress of elimination either through natural means or following through natural means or following decorporation therapy decorporation therapy

Types of bioassay Types of bioassay

In vivo

In vivo – bioassay performed on the bioassay performed on the person (e.g. whole person (e.g. whole-

body counting, thyroid

body counting, thyroid bioassay) bioassay) y) y)

In vitro

In vitro – bioassay performed on sample bioassay performed on sample removed from the person (e.g. urine, removed from the person (e.g. urine, fecal, blood samples) fecal, blood samples)

In vitro In vitro bioassays bioassays

Typically urine sample, although other

Typically urine sample, although other media can be used media can be used

You will normally collect the sample and

You will normally collect the sample and

You will normally collect the sample and

You will normally collect the sample and then pipette 1 ml into a liquid scintillation then pipette 1 ml into a liquid scintillation vial (or other appropriate medium) for vial (or other appropriate medium) for counting counting

May use fluorometry for gross U, gamma

May use fluorometry for gross U, gamma counting for Cs counting for Cs-

137, LSC for beta

137, LSC for beta-

emitters

emitters

SLIDE 25

25

Quantifying results Quantifying results

For urine bioassay, it may be possible to

For urine bioassay, it may be possible to relate the amount of isotope in the urine relate the amount of isotope in the urine to the amount in the whole body to the amount in the whole body

For example, tritium, C

For example, tritium, C-

14, and Cs

14, and Cs-

137

137 typically distribute through the entire body typically distribute through the entire body

However, it may be necessary to

However, it may be necessary to understand the biokinetics of the isotope understand the biokinetics of the isotope to be able to relate bioassay amounts to to be able to relate bioassay amounts to uptake uptake

One example One example – – Am Am-

241

241

Table Am Table Am-

3. Reference values for retention and excretion of
3. Reference values for retention and excretion of 241

241Am (% of intake) as a function of time after acute inhalation of

Am (% of intake) as a function of time after acute inhalation of moderately soluble form (Type M) by an adult; particle size = 5 μm (AMAD) moderately soluble form (Type M) by an adult; particle size = 5 μm (AMAD) Day after intake Day after intake 24 24-

h urine excretion

h urine excretion 24 24-

h fecal excretion

h fecal excretion Retained in lungs Retained in lungs Retained in body Retained in body

1 1.8E 1.8E-

01

01 1.1E+ 01 1.1E+ 01 5.8E+ 00 5.8E+ 00 5.0E+ 01 5.0E+ 01 2 2.3E 2.3E-

02

02 1.5E+ 01 1.5E+ 01 5.6E+ 00 5.6E+ 00 2.6E+ 01 2.6E+ 01 3 1.3E 1.3E-

02

02 8.0E+ 00 8.0E+ 00 5.5E+ 00 5.5E+ 00 1.5E+ 01 1.5E+ 01 5 7.2E 7.2E-

03

03 1.3E+ 00 1.3E+ 00 5.3E+ 00 5.3E+ 00 9.1E+ 00 9.1E+ 00 7 5.8E 5.8E-

03

03 2.3E 2.3E-

01

01 5.2E+ 00 5.2E+ 00 8.2E+ 00 8.2E+ 00 10 10 4.9E 4.9E-

03

03 5.7E 5.7E-

02

02 5.0E+ 00 5.0E+ 00 7.9E+ 00 7.9E+ 00 9 03 03 5 5 0 00 5 0 00 9 00 9 00 15 15 3.9E 3.9E-

03

03 4.2E 4.2E-

02

02 4.6E+ 00 4.6E+ 00 7.6E+ 00 7.6E+ 00 20 20 3.3E 3.3E-

03

03 3.7E 3.7E-

02

02 4.3E+ 00 4.3E+ 00 7.4E+ 00 7.4E+ 00 30 30 2.6E 2.6E-

03

03 2.8E 2.8E-

02

02 3.8E+ 00 3.8E+ 00 7.1E+ 00 7.1E+ 00 40 40 2.3E 2.3E-

03

03 2.1E 2.1E-

02

02 3.4E+ 00 3.4E+ 00 6.8E+ 00 6.8E+ 00 50 50 2.0E 2.0E-

03

03 1.7E 1.7E-

02

02 3.1E+ 00 3.1E+ 00 6.6E+ 00 6.6E+ 00 60 60 1.9E 1.9E-

03

03 1.3E 1.3E-

02

02 2.8E+ 00 2.8E+ 00 6.4E+ 00 6.4E+ 00 70 70 1.8E 1.8E-

03

03 1.0E 1.0E-

02

02 2.6E+ 00 2.6E+ 00 6.3E+ 00 6.3E+ 00 80 80 1.7E 1.7E-

03

03 8.2E 8.2E-

03

03 2.4E+ 00 2.4E+ 00 6.2E+ 00 6.2E+ 00 90 90 1.6E 1.6E-

03

03 6.6E 6.6E-

03

03 2.2E+ 00 2.2E+ 00 6.1E+ 00 6.1E+ 00 100 100 1.5E 1.5E-

03

03 5.4E 5.4E-

03

03 2.0E+ 00 2.0E+ 00 6.0E+ 00 6.0E+ 00

More on Am More on Am-

241

241 In vivo In vivo bioassay bioassay

Most common in a non

Most common in a non-

reactor setting is a

reactor setting is a thyroid count thyroid count

May also perform whole

May also perform whole-body counting for body counting for

May also perform whole

May also perform whole body counting for body counting for gamma emitters gamma emitters

If isotope is unknown, or if there are

If isotope is unknown, or if there are multiple isotopes, may need to also multiple isotopes, may need to also perform gamma spectroscopy to ID perform gamma spectroscopy to ID isotopes and to permit quantification isotopes and to permit quantification

Interpreting Interpreting in vivo in vivo bioassay bioassay

Will first need some sort of efficiency measurements for

Will first need some sort of efficiency measurements for your probe under the conditions of use your probe under the conditions of use

For example, with a thyroid bioassay, will have to use a

For example, with a thyroid bioassay, will have to use a neck phantom and an NIST neck phantom and an NIST-

traceable source to

traceable source to determine counting efficiency determine counting efficiency

May need other phantoms for other parts of body (e.g.

May need other phantoms for other parts of body (e.g. lungs stomach etc ) lungs stomach etc ) lungs, stomach, etc.) lungs, stomach, etc.)

Once you know your counting efficiency, it is fairly easy

Once you know your counting efficiency, it is fairly easy to determine the body (or organ) burden) from your to determine the body (or organ) burden) from your count count

This can then be used to determine amount of uptake,

This can then be used to determine amount of uptake, using your understanding of the biokinetics using your understanding of the biokinetics

From there, may be able to use information in FGR 11 or

ther sources to determine body and organ dose
ther sources to determine body and organ dose

I prefer to do the calculations once, then set up a

I prefer to do the calculations once, then set up a spreadsheet spreadsheet

Professional resources Professional resources

SLIDE 26

26

Professional organizations Professional organizations

Health Physics Society (

Health Physics Society (www.hps.org www.hps.org) )

May consider joining HPS RSO Section

May consider joining HPS RSO Section – – need not be HPS need not be HPS member member

American Academy of Health Physics

American Academy of Health Physics (www.hps1.org/aahp www.hps1.org/aahp) ) ( p g/ p p g/ p) )

Nuclear Regulatory Commission (

Nuclear Regulatory Commission (www.nrc.gov www.nrc.gov) )

State regulators (usually Health Department,

State regulators (usually Health Department, although varies by state) although varies by state)

American Association of Physicists in Medicine

American Association of Physicists in Medicine (www.aapm.org www.aapm.org) )

Each of these web pages has many links to

Each of these web pages has many links to information or to other organizations information or to other organizations

References References

Health Physics and Radiological Health

Health Physics and Radiological Health Handbook Handbook

EPA Federal Guidance Document #11

EPA Federal Guidance Document #11 (dose from uptake of radioactivity) (dose from uptake of radioactivity) ( p y) ( p y)

NCRP reports (

NCRP reports (www.ncrp.com www.ncrp.com)

ICRP reports (

ICRP reports (www.icrp.org www.icrp.org)

UNSCEAR reports (published by UN)

UNSCEAR reports (published by UN)

BEIR reports (published by NAS)

BEIR reports (published by NAS)

IAEA techdocs (

IAEA techdocs (www.iaea.or.at www.iaea.or.at) )

Other agencies and resources Other agencies and resources

State regulatory agencies usually have their own

State regulatory agencies usually have their own web pages web pages

DOE (

DOE (www.doe.gov www.doe.gov) )

EPA (

EPA (www.epa.gov www.epa.gov) ) g

DOT (

DOT (www.dot.gov www.dot.gov) )

FDA (

FDA (www.fda.gov www.fda.gov) )

ORISE HP resource CD

ORISE HP resource CD-

ROM

ROM (www.orau.gov/orise.htm www.orau.gov/orise.htm) )

HPS has an “Ask the Expert” feature on the HPS

HPS has an “Ask the Expert” feature on the HPS web page web page

Regulations Regulations Regulatory agencies Regulatory agencies

NRC/state agencies regulate most uses of

NRC/state agencies regulate most uses of radioactivity (10 CFR 20 and others) radioactivity (10 CFR 20 and others)

DOT regulates transportation of radioactive

DOT regulates transportation of radioactive materials (49 CFR 171 materials (49 CFR 171-

173)

173) ( )

EPA regulates some NORM and some

EPA regulates some NORM and some environmental discharges or contamination environmental discharges or contamination

States regulate most NORM/TENORM and

States regulate most NORM/TENORM and radiation radiation-

generating machinery

generating machinery

FDA regulates medical devices that emit

FDA regulates medical devices that emit radiation radiation

Regulations cover Regulations cover

Dose to workers (10 CFR 20.1201)

Training requirements (10 CFR 19.12)

Badging requirements (10 CFR 20.1502)

Records (10 CFR 20 2101)

Records (10 CFR 20.2101)

RSO qualifications (NUREG 1556)

RAM transportation (49 CFR 171

RAM transportation (49 CFR 171-

173)

173)

Reports to regulators (10 CFR 20.2201)

Posting and labeling areas (10 CFR 20.1902)

Radioactive waste disposal (10 CFR 20.2001)

SLIDE 27

27

To be an RSO… To be an RSO…

Training and experience requirements will

Training and experience requirements will vary according to size and complexity of vary according to size and complexity of program program

Small programs may have part

Small programs may have part-time RSO time RSO

Small programs may have part

Small programs may have part-time RSO time RSO as a collateral duty as a collateral duty

Large programs will need a full

Large programs will need a full-

time RSO

time RSO

RSO is responsible for entire program

RSO must have authority from licensee to

RSO must have authority from licensee to carry out duties properly carry out duties properly

Controlling radiological areas Controlling radiological areas

Some areas require administrative and/or

Some areas require administrative and/or engineering controls engineering controls

One form of administrative controls is

One form of administrative controls is

One form of administrative controls is

One form of administrative controls is posting a room or area as a radiologically posting a room or area as a radiologically controlled area controlled area

Other areas require audible and visual

Other areas require audible and visual alarms and other controls alarms and other controls

Posting requirements Posting requirements

Radiation area

Radiation area – – can exceed 5 mrem in 1 hr can exceed 5 mrem in 1 hr

High radiation area

High radiation area – – can exceed 100 mrem in 1 hr can exceed 100 mrem in 1 hr

Contamination area

Contamination area – – more than 1000 dpm/100 more than 1000 dpm/100

2

f bl t i ti ( t 15 000 f bl t i ti ( t 15 000 cm cm2 of removable contamination (up to 15,000

f removable contamination (up to 15,000

dpm total) dpm total)

Radioactive materials storage area

Radioactive materials storage area – – contains more contains more than 10 times exemption limits of isotopes (vary by than 10 times exemption limits of isotopes (vary by isotope) isotope)

“Sum of fractions” rule applies

Other dose control features Other dose control features

HRAs must be locked and have entry controls

HRAs must be locked and have entry controls

Irradiator rooms must have audible and

Irradiator rooms must have audible and visual alarms visual alarms

Doors must be interlocked to retract source if

Doors must be interlocked to retract source if

pened
pened
Must have visual confirmation room is empty

Must have visual confirmation room is empty prior to exposing source or energizing prior to exposing source or energizing machine machine

Reports to regulators Reports to regulators

Loss of radioactive materials

Personnel exceeding dose limits

Personnel exceeding dose limits Some instances of skin contamination or Some instances of skin contamination or

Some instances of skin contamination or

Some instances of skin contamination or uptake of radioactive materials uptake of radioactive materials

Other incidents or emergencies involving

Other incidents or emergencies involving radioactive materials (for example, a fire radioactive materials (for example, a fire in a RAM storage area) in a RAM storage area)

Transportation Transportation

RAM must be properly packaged according

RAM must be properly packaged according to isotope(s) and activity present to isotope(s) and activity present

Package and vehicle external rad levels

Package and vehicle external rad levels determine mode of shipment vehicle determine mode of shipment vehicle determine mode of shipment, vehicle determine mode of shipment, vehicle placarding, and other requirements placarding, and other requirements

Package rad levels and amount of activity

Package rad levels and amount of activity present determine labeling on package present determine labeling on package

Must attend DOT training every 3 years

Must attend DOT training every 3 years

SLIDE 28

28

More transportation stuff More transportation stuff

May need shipping papers and/or manifest that

May need shipping papers and/or manifest that must be easily accessible by driver must be easily accessible by driver

All RAM must be properly blocked and braced in

All RAM must be properly blocked and braced in vehicle vehicle vehicle vehicle

Vehicle should be exclusive

Vehicle should be exclusive-

use if possible (easier

use if possible (easier with company vehicle) with company vehicle)

RAM must be secured against unauthorized

RAM must be secured against unauthorized removal at all time removal at all time

Vehicle may require placarding, depending on

Vehicle may require placarding, depending on activity and radiation levels activity and radiation levels

Receiving radioactive packages Receiving radioactive packages

Covered in 10 CFR 20.1906

Covered in 10 CFR 20.1906

Must have procedure for receiving rad

Must have procedure for receiving rad packages packages p g p g

Must survey (radiation and possibly

Must survey (radiation and possibly contamination) within 3 hours of receipt contamination) within 3 hours of receipt

Must inspect package for damage

Must inspect package for damage

Notify carrier (e.g. FedEx) if package is

Notify carrier (e.g. FedEx) if package is damaged or contaminated) damaged or contaminated)

Dose limits Dose limits

5 rem/yr

5 rem/yr – – Radiation workers (WB) Radiation workers (WB)

0.1 rem/yr

0.1 rem/yr – – everyone else everyone else

50 rem/yr

50 rem/yr – – any internal organ any internal organ 15 rem/yr 15 rem/yr lens of eye lens of eye

15 rem/yr

15 rem/yr – lens of eye lens of eye

50 rem/yr

50 rem/yr – – skin and extremities skin and extremities

Can exceed dose limits for Planned Special

Can exceed dose limits for Planned Special Exposure Exposure – – several requirements in 10 several requirements in 10 CFR 20.1206 CFR 20.1206

Minors are limited to 10% of adult doses

Pregnant workers Pregnant workers

Pregnancy must be declared voluntarily

Pregnancy must be declared voluntarily and in writing to the RSO and in writing to the RSO

Worker must be given fetal badge (unless

Worker must be given fetal badge (unless she works with radiation that won’t be she works with radiation that won’t be she works with radiation that won t be she works with radiation that won t be detected) detected)

Fetal dose limits are 500 mrem during the

Fetal dose limits are 500 mrem during the entire pregnancy, 50 mrem in any month entire pregnancy, 50 mrem in any month

Worker may un

Worker may un-

declare pregnancy at any

declare pregnancy at any time time

ALARA ALARA

As

s Low

w As

s Reasonably easonably Achievable chievable

Should take all reasonable measures to

Should take all reasonable measures to reduce radiation dose as much as possible reduce radiation dose as much as possible

Need not take unreasonable measures

All employees must be trained in ALARA

May need to put together an ALARA plan

May need to put together an ALARA plan for your company, depending on type of for your company, depending on type of work performed work performed

Training requirements Training requirements

All

All radiation workers require initial training radiation workers require initial training before before working with radiation or working with radiation or radioactivity radioactivity

All

All radiation workers must receive radiation workers must receive refresher training annually refresher training annually

Ancillary workers may require training,

Ancillary workers may require training, depending on work duties depending on work duties

Maintenance, housekeeping, etc.

SLIDE 29

29

Records to keep Records to keep

Training records

Dose and exposure reports

Radiation surveys

Instrument calibration sheets

Maintenance and repair for all radiation

Maintenance and repair for all radiation i i equipment equipment

Sealed source inventory and leak tests

Internal audit and external inspection reports

RAM inventories

Shipping documents

Waste disposal

Incident reports

Training is important! Training is important!

Make sure everyone receives the training

Make sure everyone receives the training required by regulations required by regulations

Keep training records for all attendees

Keep training records for all attendees

Ensure content includes regulatory

Ensure content includes regulatory requirements requirements

Go over ALARA, pregnant worker

Go over ALARA, pregnant worker program, dose limits, and site program, dose limits, and site-

specific

specific information information

Radioactive waste Radioactive waste

Short

Short-

lived waste can be stored for decay

lived waste can be stored for decay (usually <90 day half (usually <90 day half-

life)

life)

Long

Long-

lived solid waste must be shipped for

lived solid waste must be shipped for disposal to a licensed facility disposal to a licensed facility disposal to a licensed facility disposal to a licensed facility

Liquid wastes can sometimes be disposed

f into sanitary sewer system
f into sanitary sewer system

Some wastes (animal carcasses and liquid

Some wastes (animal carcasses and liquid scintillation vials with H scintillation vials with H-

3 and C

3 and C-

14) can

14) can be treated as non be treated as non-

radioactive

radioactive – – called “de called “de minimis” minimis”

Waste storage area Waste storage area

Must be capable of safely storing waste

Must be capable of safely storing waste through DIS period or until shipping through DIS period or until shipping

Must be dry and secure

Must be dry and secure

Should have sprinkler system in case of fire

Should have sprinkler system in case of fire

Should be inspected periodically to ensure

Should be inspected periodically to ensure waste package integrity waste package integrity

Should also survey periodically for radiation

Should also survey periodically for radiation and contamination levels and contamination levels

Sewer disposal Sewer disposal

Only for authorized liquids (nothing

Only for authorized liquids (nothing hazardous) hazardous)

Must calculate average activity

Must calculate average activity concentrations, based on flow of water concentrations, based on flow of water through sewer at facility through sewer at facility

Average activity concentrations must be

Average activity concentrations must be less than those in CFRs or state less than those in CFRs or state regulations for each isotope regulations for each isotope

ALI and DAC calculations ALI and DAC calculations

SLIDE 30

30

Airborne radioactivity Airborne radioactivity

ALI

ALI – – allowable limit for intake allowable limit for intake – – the the amount of radioactivity that will give a amount of radioactivity that will give a person 5 rem WB or 50 rem to an organ person 5 rem WB or 50 rem to an organ DAC DAC d i d i t ti d i d i t ti

DAC

DAC – derived air concentration derived air concentration – radioactivity concentration that will give radioactivity concentration that will give an unprotected worker 1 ALI if breathed an unprotected worker 1 ALI if breathed for 2000 hours (listed in FGR 11) for 2000 hours (listed in FGR 11)

Can use ALI to determine dose from

Can use ALI to determine dose from uptake of radioactivity uptake of radioactivity

DAC example DAC example

A worker who works in an atmosphere of 20

A worker who works in an atmosphere of 20 DAC for 10 hours will receive 200 DAC DAC for 10 hours will receive 200 DAC-

hrs of

hrs of exposure exposure

Workers are allowed 2000 DAC

Workers are allowed 2000 DAC-hrs in a year, hrs in a year, Workers are allowed 2000 DAC Workers are allowed 2000 DAC hrs in a year, hrs in a year, which gives 5 rem WB or 50 rem organ dose which gives 5 rem WB or 50 rem organ dose

So 200 DAC

So 200 DAC-

hrs will give a worker 10% of

hrs will give a worker 10% of allowable dose for the year allowable dose for the year

OR working 2000 hrs in 1 DAC atmosphere while

OR working 2000 hrs in 1 DAC atmosphere while wearing a respirator with a protection factor of wearing a respirator with a protection factor of 10 will also give 200 DAC 10 will also give 200 DAC-

hrs of exposure

hrs of exposure

ALI example ALI example

Ingesting 1 ALI will give a worker 5 rem

Ingesting 1 ALI will give a worker 5 rem WB or 50 rem organ dose WB or 50 rem organ dose

So a worker who ingests 20% of the ALI

So a worker who ingests 20% of the ALI g for a particular isotope will receive 20% of for a particular isotope will receive 20% of their allowable dose for the year their allowable dose for the year

ALI and DAC values are given in FGR 11

ALI and DAC values are given in FGR 11 (an EPA document) (an EPA document)

ALI example ALI example

A worker accidentally ingests 10

A worker accidentally ingests 10 μCi of Cs Ci of Cs-

137 in powdered form

137 in powdered form

ALI for Cs

ALI for Cs-137 is 40 137 is 40 μCi with no target Ci with no target

ALI for Cs

ALI for Cs 137 is 40 137 is 40 μCi with no target Ci with no target

rgan
rgan
Worker ingestion is 0.25 ALI

Worker ingestion is 0.25 ALI

Worker receives dose of 1.25 rem (25% of

Worker receives dose of 1.25 rem (25% of 5 rem WB limit) 5 rem WB limit)

Common tasks Common tasks Surveys Surveys

Periodic radiation and/or contamination

Periodic radiation and/or contamination surveys surveys

Daily, weekly, or monthly, depending on

perating circumstances
perating circumstances
perating circumstances
perating circumstances

Frequency depends on level of use

“Special” surveys

“Special” surveys

Post

Post-

work surveys if handling isotopes

work surveys if handling isotopes

Post

Post-

maintenance

maintenance

After any significant change or work that

After any significant change or work that could affect shielding or other characteristics could affect shielding or other characteristics

SLIDE 31

31

Pre Pre-

survey checks

survey checks

Confirm proper detector for survey

Verify meter calibrated within last year

Verify physical integrity of meter and cable

Perform battery check

Perform response check against source of

Perform response check against source of known strength (+/ known strength (+/-

20% of ave. counts)

20% of ave. counts)

Verify switch positions if appropriate

Verify switch positions if appropriate (audible “on” and response “f” or “fast” (audible “on” and response “f” or “fast”

Contamination surveys Contamination surveys

Perform pre

Perform pre-

survey meter checks

survey meter checks

Hold detector no more than ½ inch from

Hold detector no more than ½ inch from surface to be surveyed surface to be surveyed

Move detector at no more than 2”/second

Move detector at no more than 2”/second

Survey 100% of surface if possible

Survey 100% of surface if possible

Watch probe to ensure proper survey while

Watch probe to ensure proper survey while listening to detector listening to detector – – if you hear an increase if you hear an increase in count rate, see if area is contaminated in count rate, see if area is contaminated

Contamination surveys (con’t) Contamination surveys (con’t)

Record any area in which count rate

Record any area in which count rate increases appreciably (e.g. 50 cpm for a increases appreciably (e.g. 50 cpm for a GM, 100 GM, 100 – 200 for thin 200 for thin-

xtal NaI)

xtal NaI) , )

Must record net cpm and dpm on survey

Must record net cpm and dpm on survey record record

Cpm

Cpm – – bkg = net cpm bkg = net cpm

Cpm/meter efficiency = dpm

Example Example

Say background levels are 50 cpm with a

Say background levels are 50 cpm with a GM probe GM probe

At a certain location you read 130 cpm

At a certain location you read 130 cpm

At a certain location, you read 130 cpm

At a certain location, you read 130 cpm

130

130-

50 = 80 net cpm

50 = 80 net cpm

If meter efficiency is 40%:

If meter efficiency is 40%:

dpm = 80 cpm/0.40 = 200 dpm

Radiation dose rate surveys Radiation dose rate surveys

Use appropriate meter

Ion chamber, micro

Ion chamber, micro-

R meter, etc.

R meter, etc.

For general area surveys, hold meter at waist

For general area surveys, hold meter at waist level (about 1 m above ground) and walk slowly level (about 1 m above ground) and walk slowly through area being surveyed through area being surveyed through area being surveyed through area being surveyed

“General area” is 30 cm (1 foot) from any

“General area” is 30 cm (1 foot) from any surface surface

“On contact” used to measure hot spots

“On contact” used to measure hot spots – – usually taken to be 1” from surface or point usually taken to be 1” from surface or point surveyed surveyed

Record highest readings as well as area readings

Some trouble Some trouble-

shooting:

shooting: common problems common problems

Elevated counts, no contamination

Elevated counts, no contamination

Spurious high and/or low counts or erratic

Spurious high and/or low counts or erratic readings readings

No readings (including background)

No readings (including background)

SLIDE 32

32 Elevated count rate Elevated count rate – – possible causes possible causes

Light leak (scintillation probes only)

Cover probe, then uncover; compare counts

Light leak indicated if counts

Light leak indicated if counts ↑ when probe exposed when probe exposed to light to light

Contaminated probe

Move probe a meter or so from survey location

If high counts remain, probe may be contaminated

High radiation levels

Hold probe near body

If readings drop, high counts may be due to high

If readings drop, high counts may be due to high radiation levels radiation levels

Erratic readings Erratic readings

Most likely cause is a short or open circuit

Most likely cause is a short or open circuit in the cable (very common) in the cable (very common)

If high or low counts can be reproduced

If high or low counts can be reproduced g p g p by jiggling cable or holding probe in a by jiggling cable or holding probe in a certain position relative to meter, you certain position relative to meter, you should suspect a cable problem should suspect a cable problem

Use another meter to survey location OR

Use another meter to survey location OR change cable on problematic meter change cable on problematic meter

No readings No readings

Most likely cause is dead batteries

Perform battery check

Replace batteries

Also possible that detector is broken

r disconnected
r disconnected

If batteries are OK, use check source to

If batteries are OK, use check source to test meter response test meter response

Examine detector and detector window

Examine detector and detector window for breakage, replace if necessary for breakage, replace if necessary

If all else fails…. If all else fails….

Change cable and probe OR

Change cable and probe OR

Send meter for re

Send meter for re-

calibration

calibration Send meter for repair Send meter for repair

Send meter for repair

Send meter for repair

Buy a new meter

Buy a new meter

Smear wipe surveys Smear wipe surveys

May have to perform smear wipe survey for

May have to perform smear wipe survey for isotopes with low meter efficiency (such as isotopes with low meter efficiency (such as H-

3, C

3, C-

14, S

14, S-

35)

35)

Smear wipes are dry filter paper, wiped over

Smear wipes are dry filter paper, wiped over 100 cm 100 cm2

2 Want to avoid cross

Want to avoid cross-

contamination of wipes

contamination of wipes

Want to avoid cross

Want to avoid cross-

contaminating surfaces

contaminating surfaces

Usually counted in proportional counter,

Usually counted in proportional counter, gamma counter, or scintillation counter gamma counter, or scintillation counter

Importance of surveys Importance of surveys

If you do not have dosimetry records,

If you do not have dosimetry records, your survey records are the only means your survey records are the only means you have to combat unjustified radiation you have to combat unjustified radiation injury claims injury claims j y j y

For this reason, properly performing

For this reason, properly performing complete surveys and retaining survey complete surveys and retaining survey records is crucial records is crucial

Equally important is ensuring your survey

Equally important is ensuring your survey equipment is properly maintained and equipment is properly maintained and calibrated calibrated

SLIDE 33

33

Sealed source checks Sealed source checks

Required to inventory sealed sources

Required to inventory sealed sources either quarterly or semi either quarterly or semi-

annually

annually

Required to leak test sealed sources with

Required to leak test sealed sources with q same periodicity same periodicity

Some sources do not require leak testing

Some sources do not require leak testing – – check your license or regulations check your license or regulations

Performing a leak test does not

Performing a leak test does not necessarily count as an inventory check necessarily count as an inventory check – – must record both events separately must record both events separately

Leak testing Leak testing

Must report significant source leakage

Must report significant source leakage (check your regulations for amount) (check your regulations for amount)

Must be able to show that test

Must be able to show that test

Must be able to show that test

Must be able to show that test methodology will detect at or below methodology will detect at or below contamination limit contamination limit

Several acceptable methods of leak testing

Several acceptable methods of leak testing and inventory and inventory

Ability to detect leaking source Ability to detect leaking source

Standard is 185 Bq/source

185 Bq = 11,100 dpm

185 Bq = 11,100 dpm If you have (for example) 10% counting If you have (for example) 10% counting

If you have (for example) 10% counting

If you have (for example) 10% counting efficiency, 11,100 dpm will give you 1110 efficiency, 11,100 dpm will give you 1110 cpm cpm

Then you can point out that this is enough

Then you can point out that this is enough counts to “see” above your background counts to “see” above your background

Leak test methods Leak test methods

Best to directly wipe 100% of source

Best to directly wipe 100% of source capsule capsule

May wish to consider holding source and wipe

May wish to consider holding source and wipe May wish to consider holding source and wipe May wish to consider holding source and wipe with tongs to reduce finger dose with tongs to reduce finger dose

Can also wipe area around source if

Can also wipe area around source if source is not directly accessible source is not directly accessible

Can also wipe outside of source holder

Can also wipe outside of source holder

Inventory methods Inventory methods

Best to visually sight the source

Can also verify source in sealed container

Can also verify source in sealed container that has been sealed since last inventory that has been sealed since last inventory

Can also verify operability of device that

Can also verify operability of device that relies on presence of source relies on presence of source

Other methods may be acceptable

Other methods may be acceptable – – check check with the source/device manufacturer and with the source/device manufacturer and regulators regulators

Radiation safety program Radiation safety program management management

SLIDE 34

34

Priorities Priorities

Keep people safe and healthy

Violate as few regulations as possible

Provide HP support services to users

Remember that your priorities are not

Remember that your priorities are not e e be t at you p o t es a e

t

e e be t at you p o t es a e

t

necessarily those of your management or necessarily those of your management or users users

Authorized users are most concerned about their

Authorized users are most concerned about their research research

A university is most concerned about grant

A university is most concerned about grant dollars, publications, and (hopefully) education dollars, publications, and (hopefully) education

My primary goals as RSO My primary goals as RSO

Make sure that we keep our license

Make sure that we keep our license

Keep our program out of the news

Keep our program out of the news

Make sure our physicians and researchers

Make sure our physicians and researchers l ti l f th i t f l ti l f th i t f are relatively unaware of the existence of are relatively unaware of the existence of Radiation Safety Radiation Safety

Unfortunately, our job is like people who do

Unfortunately, our job is like people who do lighting in theater lighting in theater – – nobody knows we’re nobody knows we’re there unless we screw up there unless we screw up

Policies and procedures Policies and procedures

Policies give the big picture as to how radiation

Policies give the big picture as to how radiation and radioactivity are used at our facility and radioactivity are used at our facility

Ex: pregnant worker policy

Procedures are the little picture items that tell us

Procedures are the little picture items that tell us how to perform each task to comply with the how to perform each task to comply with the policies policies po c es po c es

Ex: where a fetal dosimeter is worn

Both are necessary, and both should be

Both are necessary, and both should be reviewed and approved by management and/or reviewed and approved by management and/or RSC RSC

Both should be in writing and easily available to

Both should be in writing and easily available to all radiation workers and authorized users as the all radiation workers and authorized users as the RSM and SOPs RSM and SOPs

Radiation Safety’s role…. Radiation Safety’s role….

Propose (and draft) new policies and

Propose (and draft) new policies and procedures as necessary procedures as necessary

Enforce compliance with policies and

Enforce compliance with policies and

Enforce compliance with policies and

Enforce compliance with policies and procedures via inspection procedures via inspection

Determine appropriate corrective and/or

Determine appropriate corrective and/or disciplinary actions in cases of non disciplinary actions in cases of non-

compliance

compliance

Purpose of license Purpose of license

Gives the licensee permission to use

Gives the licensee permission to use radioactive materials radioactive materials

Sets conditions for that use

May list specific users and/or specific

May list specific users and/or specific sources sources

For example

For example – – irradiator sources will probably irradiator sources will probably be listed by serial number and activity be listed by serial number and activity

Incidents and emergencies Incidents and emergencies

Need to train workers in how to respond to

Need to train workers in how to respond to unexpected events unexpected events

Also need to train Security

Should maintain records of all radiological

Should maintain records of all radiological incidents incidents incidents incidents

May need to notify regulators, depending on

May need to notify regulators, depending on reporting requirements reporting requirements

I will often inform regulators of incidents even if a

I will often inform regulators of incidents even if a formal report is not required formal report is not required – – helps build good helps build good working relationship, and regulators may be able to working relationship, and regulators may be able to suggest actions I haven’t thought of suggest actions I haven’t thought of

SLIDE 35

35

Incidents and emergencies (II) Incidents and emergencies (II)

Encourage reporting incidents to RS

We don’t penalize honest mistakes that lead to spills,

We don’t penalize honest mistakes that lead to spills, skin contamination, etc. skin contamination, etc.

Should have policy as to what level of incident your

Should have policy as to what level of incident your rad workers can address on their own (e.g. “major” rad workers can address on their own (e.g. “major”

vs. “minor” spills)
vs. “minor” spills)

Train people in immediate actions to limit

Train people in immediate actions to limit incident (i.e. “SWIM” for spills) incident (i.e. “SWIM” for spills)

Should investigate serious or potentially serious

Should investigate serious or potentially serious incidents to find out what happened, why, and incidents to find out what happened, why, and what can be learned what can be learned

Working with the RSC Working with the RSC

RSC has three primary functions

RSC has three primary functions

Oversee activities of RS and RSO

Support RSO with advice in areas beyond

Support RSO with advice in areas beyond RSO’s experience RSO’s experience

Determine need for disciplinary or corrective

Determine need for disciplinary or corrective actions if necessary actions if necessary

RSO should keep RSC informed of

RSO should keep RSC informed of incidents as they occur incidents as they occur

RSC can be a good sounding board for

RSC can be a good sounding board for policy changes, SOPs, etc. policy changes, SOPs, etc.

Working with management Working with management

Need management support to have an effective radiation

Need management support to have an effective radiation safety program safety program

Controversial or unpopular policies are more palatable if

Controversial or unpopular policies are more palatable if supported by management supported by management

May need management to support disciplinary actions

So management needs to be kept in the loop!

It’s best to consult with management early especially if

It s best to consult with management early, especially if

It s best to consult with management early, especially if decisions involve added cost, or researchers with lots of decisions involve added cost, or researchers with lots of funding funding

Should be able to explain to management the reasons

Should be able to explain to management the reasons for any controversial actions for any controversial actions

Regulatory requirements that were violated (or need to be met)

Possible litigation issues

JCAHO (if a medical center)

Working with regulators Working with regulators

Two approaches to working with

Two approaches to working with regulators regulators – – adversarial or cooperative adversarial or cooperative

Usually best to try to work with regulators

Usually best to try to work with regulators

Can sometimes get useful support from

Can sometimes get useful support from l if hi l i ki l if hi l i ki regulators if nothing else is working regulators if nothing else is working

Need for extra staff

Needed policy changes

Proper role of RS or RSU

Cultural differences: Management Cultural differences: Management

Being cynical, I assume that management only

Being cynical, I assume that management only wants things to run smoothly at low cost with no wants things to run smoothly at low cost with no lawsuits or bad press lawsuits or bad press

This means that you will have to justify policy

This means that you will have to justify policy changes extra expenses (equipment staff ) in changes extra expenses (equipment staff ) in changes, extra expenses (equipment, staff...) in changes, extra expenses (equipment, staff...) in terms of management’s concerns terms of management’s concerns

Similarly, if enforcement actions will affect a highly

Similarly, if enforcement actions will affect a highly funded researcher or a medical department, you funded researcher or a medical department, you should be prepared to justify them in terms should be prepared to justify them in terms management will relate to (JCAHO, fines, litigation management will relate to (JCAHO, fines, litigation prevention, etc.) prevention, etc.)

My general approach to being RSO My general approach to being RSO

Assume people want to do things correctly, but

Assume people want to do things correctly, but will sometimes make mistakes will sometimes make mistakes

If disciplinary actions are required, they should

If disciplinary actions are required, they should be appropriate be appropriate

Keep people informed as much as possible

Keep people informed as much as possible Keep people informed as much as possible Keep people informed as much as possible

Work with people in person instead of via

Work with people in person instead of via phone, e phone, e-

mail, or letters

mail, or letters

Get out and about to visit labs and meet PIs

Do some of the work (inspections, training, etc.)

Do some of the work (inspections, training, etc.) instead of just attending meetings and writing policies instead of just attending meetings and writing policies and procedures and procedures

SLIDE 36

36

Inspecting in your facility Inspecting in your facility

Laboratory inspections Laboratory inspections – – a general a general approach approach

We are not the radiation Gestapo

We are not the radiation Gestapo -

we

we support research and medical care support research and medical care

Inspections are necessary to ensure

Inspections are necessary to ensure compliance with regulations, policies, and compliance with regulations, policies, and p g , p , p g , p , good practices good practices

We make every effort to make our

We make every effort to make our inspections objective and fair inspections objective and fair

Minor violations may be corrected on the

Minor violations may be corrected on the spot without being cited spot without being cited

Everything must be documented

Everything must be documented

U of R inspection stats U of R inspection stats

Compliance rate is about 90%

About 75% of violations we find are minor

About 75% of violations we find are minor and are not cited and are not cited W d t b t 650 i ti W d t b t 650 i ti

We conduct about 650 inspections

We conduct about 650 inspections annually and find about 100 violations annually and find about 100 violations among all permit holders among all permit holders

Most cited and uncited violations are

Most cited and uncited violations are directly or indirectly due to failing to directly or indirectly due to failing to perform surveys perform surveys

Inspection cycle Inspection cycle

“Good” labs (those with no violations in

“Good” labs (those with no violations in past 12 months) are inspected semi past 12 months) are inspected semi-

annually

annually

Everyone else (including new permit

Everyone else (including new permit holders) are inspected quarterly holders) are inspected quarterly

Semi

Semi-

annual inspections are more

annual inspections are more thorough and include a formal inventory thorough and include a formal inventory verification verification

Old system Old system

RS was responsible for monthly contamination

RS was responsible for monthly contamination surveys, which doubled as “inspection” surveys, which doubled as “inspection”

Due to under

Due to under-

staffing, other duties and large

staffing, other duties and large number of labs, most monthly surveys were number of labs, most monthly surveys were missed missed

When inspections were performed, they were

When inspections were performed, they were cursory at best cursory at best

An external audit found violations in 70

An external audit found violations in 70-

80% of

80% of labs labs – – mostly failure to perform needed surveys mostly failure to perform needed surveys and eating in posted areas and eating in posted areas

Changes we made Changes we made

Labs became responsible for all monthly surveys

Began quarterly inspection cycle

Developed inspection checklist and gave copies

Developed inspection checklist and gave copies to all permit holders to all permit holders

Began intensive training on radiation safety

Began intensive training on radiation safety policies during initial and refresher training, policies during initial and refresher training, along with scheduling meetings with all labs to along with scheduling meetings with all labs to explain policy changes explain policy changes

Gradually ratcheted down on labs over a year to

Gradually ratcheted down on labs over a year to get them used to the new system and expected get them used to the new system and expected performance standards performance standards

SLIDE 37

37

Results of policy changes Results of policy changes

Increased staff from 4 to 6 tech staff

Compliance changed from 20%

Compliance changed from 20%→90% 90%

No violations in last 3 regulatory inspections

Freed up enough staff time to clean up

Freed up enough staff time to clean up l t l t 3 l t l t 3 d d t d d t legacy waste, close out 3 un legacy waste, close out 3 un-

needed waste

needed waste rooms, re rooms, re-

write RSM, and make other

write RSM, and make other needed changes needed changes

More thorough inspections also gives more

More thorough inspections also gives more time to talk with rad workers during visits time to talk with rad workers during visits – – improves relations improves relations

UR’s “Chief Inspector” UR’s “Chief Inspector”

One person performs most of our inspections

Our inspector is very professional, calm, thorough,

Our inspector is very professional, calm, thorough, fair, and can’t be talked into looking the other way fair, and can’t be talked into looking the other way

Former Air Force Master Sergeant

Users respect our inspector’s detailed knowledge of

Users respect our inspector’s detailed knowledge of di i f d hi illi k i di i f d hi illi k i radiation safety and his willingness to take time to radiation safety and his willingness to take time to work with them during inspections work with them during inspections

Having the same person do virtually all inspections

Having the same person do virtually all inspections is a plus because of the heightened familiarity with is a plus because of the heightened familiarity with rad workers rad workers

Inspection preparation Inspection preparation

Pull file on permit holder

Review past inspection reports

What isotopes do they work with?

Are there any permit conditions or

Are there any permit conditions or y p y p restrictions? restrictions?

How active and how large is their program?

Assemble and check equipment

Appropriate meter for survey(s)

Smear wipes (if appropriate)

During inspection During inspection

Review paperwork

Review paperwork

Observe work practices

Observe work practices

Quiz rad workers on basic “level of

Quiz rad workers on basic “level of knowledge” questions knowledge” questions g q g q

Perform confirmatory contam. survey

Perform confirmatory contam. survey

Perform radiation level survey

Perform radiation level survey

Use this to confirm dosimetry not needed, as

Use this to confirm dosimetry not needed, as long as rad levels are less than 0.2 mr/hr in long as rad levels are less than 0.2 mr/hr in an accessible area an accessible area

Paperwork review Paperwork review

Inventory verification

Waste container inventory sheets

Stock vial record sheets

Monthly survey review

Check for training and refresher training

Check for training and refresher training certificates certificates

Review dosimetry reports (if badges

Review dosimetry reports (if badges issued) issued)

Work practices Work practices

Are workers properly garbed (lab coats,

Are workers properly garbed (lab coats, gloves, no bare legs or feet)? gloves, no bare legs or feet)?

Are surveys performed properly?

Are surveys performed properly?

Check for eating drinking or food storage

Check for eating drinking or food storage

Check for eating, drinking, or food storage

Check for eating, drinking, or food storage in posted areas in posted areas

Do workers survey hands frequently

Do workers survey hands frequently during work with isotope? during work with isotope?

Look at radiological and general

Look at radiological and general housekeeping housekeeping

SLIDE 38

38 What every radiation worker needs What every radiation worker needs to know: to know:

Laboratory isotope use information

Isotope(s), half

Isotope(s), half-

lives, survey methods

lives, survey methods

Dose limits

Rad workers, pregnant workers, public

Work practices

Survey technique, bremsstrahlung, PPE

General information

Regulatory agency, who is RSO, etc.

Surveys Surveys

Inspection contamination surveys are

Inspection contamination surveys are confirmatory in nature confirmatory in nature

They do not substitute for the lab’s required

They do not substitute for the lab’s required surveys surveys

Radiation surveys are performed only by

Radiation surveys are performed only by RSU RSU

Used to justify not badging most of our

Used to justify not badging most of our research rad workers research rad workers

Rad levels can be used as proxy for personal

Rad levels can be used as proxy for personal dosimeters dosimeters

Violations Violations

Two categories

Two categories – – major and minor major and minor

Minor violations (meter out

Minor violations (meter out-

of
f-
cal, minor

cal, minor paperwork problems, etc.) can often be corrected paperwork problems, etc.) can often be corrected

n the spot
n the spot

Major violations (inappropriate disposal of rad

Major violations (inappropriate disposal of rad waste, failure to survey, etc.) are cited in report waste, failure to survey, etc.) are cited in report (with concurrence of RSO) (with concurrence of RSO)

Permit holders can appeal violations to RSC

Need to reply in writing in two weeks with

Need to reply in writing in two weeks with corrective actions taken corrective actions taken

Enforcement actions Enforcement actions

Any researcher who receives more than 4 major

Any researcher who receives more than 4 major violations in any continuous six violations in any continuous six-

month period is

month period is subject to disciplinary or corrective actions subject to disciplinary or corrective actions

Actions are recommended by RSO and approved

Actions are recommended by RSO and approved by RSC by RSC by RSC by RSC

Failure to correct problems or to reply in a

Failure to correct problems or to reply in a timely manner is considered a major violation timely manner is considered a major violation

We warn permit holders when they reach 3

We warn permit holders when they reach 3 violations or greater violations or greater

What corrective or disciplinary What corrective or disciplinary actions are available? actions are available?

Mandatory refresher training for lab

Special meeting of lab staff with RSO

1-

on
n-
1 training with individual rad workers

1 training with individual rad workers

Temporary suspension of a worker

Temporary suspension of a worker p y p p y p

Temporary permit suspension

Temporary suspension of ability to order

Temporary suspension of ability to order isotope isotope

Permanent suspension of individual

Permanent suspension of individual worker or of permit worker or of permit

After the inspection After the inspection -

RS

RS

We maintain records of compliance rate

We maintain records of compliance rate and number of violations and number of violations

Violations are tracked by area

Violations are tracked by area

Violations are tracked by area

Violations are tracked by area

Most common violations are failure to survey,

Most common violations are failure to survey, contamination in lab, meters out of contamination in lab, meters out of calibration, and radioactive material security calibration, and radioactive material security

Summary statistics are presented to RSC

Summary statistics are presented to RSC annually annually

SLIDE 39

39 After the inspection After the inspection – – rad worker rad worker

Inspection report sent within 1 week of

Inspection report sent within 1 week of inspection inspection

Worker has two weeks to reply to any

Worker has two weeks to reply to any violations with corrective actions or to violations with corrective actions or to contest violation contest violation

May have follow

May have follow-

up inspection, depending

up inspection, depending

n number of violations
n number of violations

Summary Summary

Managing a radiation safety program is

Managing a radiation safety program is not simple, but it need not be all not simple, but it need not be all-

consuming

consuming

Important to be able to understand and

Important to be able to understand and work with a wide variety of people, each work with a wide variety of people, each with their own priorities with their own priorities

Inspections are a vital part of any good RS

Inspections are a vital part of any good RS program program

Inspections need not be adversarial

Inspections need not be adversarial

Regulatory Inspections Regulatory Inspections Regulatory inspections Regulatory inspections

Most licensees will be inspected annually

Inspections may last from a half day to several

Inspections may last from a half day to several days days 1 or more inspectors may show up at your door 1 or more inspectors may show up at your door

1 or more inspectors may show up at your door

Inspectors have the right to see any part of your

Inspectors have the right to see any part of your radiation safety program and to speak with any radiation safety program and to speak with any worker worker

You have the right to accompany the inspectors

You have the right to accompany the inspectors during their visit during their visit

What they’ll look at What they’ll look at

Training records

Dosimetry records

Survey records

Survey records Inventory records Inventory records

Inventory records

Shipping papers (if appropriate)

Waste records (if appropriate)

Work practices

Meter calibration and maintenance records

Equipment service records (if appropriate)

Other things that might happen Other things that might happen

Interviews with management to confirm

Interviews with management to confirm support for Radiation Safety support for Radiation Safety

Interviews with non

Interviews with non-

rad workers

rad workers

General housekeeping inspection

General housekeeping inspection

Discussion of overall program with RSO

Discussion of overall program with RSO

Review of Radiation Safety Committee

Review of Radiation Safety Committee records records

Entrance and exit interviews

Entrance and exit interviews

SLIDE 40

40

If you get a violation… If you get a violation…

“Apparent violations” noted during exit interview

“Apparent violations” noted during exit interview – must be confirmed by formal inspection report must be confirmed by formal inspection report

Try to correct violation during inspection and

Try to correct violation during inspection and notify inspectors of corrective actions notify inspectors of corrective actions T k ll i l ti i l T k ll i l ti i l th i t th i t

Take all violations seriously

Take all violations seriously – they are serious to they are serious to the inspectors the inspectors

You may contest any violations, but should limit

You may contest any violations, but should limit this to those for which you have good this to those for which you have good documentation documentation

You must reply in writing, accepting violation

You must reply in writing, accepting violation and noting corrective actions taken to resolve and noting corrective actions taken to resolve

About your license…. About your license…. Licensing Licensing

Whether writing a new license, a license

Whether writing a new license, a license amendment, or a license renewal, try to amendment, or a license renewal, try to stay as simple, as general, and as “clean” stay as simple, as general, and as “clean” y p , g , y p , g , as possible as possible

Simplicity Simplicity

Try to use the simplest language, procedures,

Try to use the simplest language, procedures, and the simplest approach possible when and the simplest approach possible when addressing specific issues in the license addressing specific issues in the license application application application application

If you inherit a needlessly complex license,

If you inherit a needlessly complex license, consider the degree to which you can simplify it consider the degree to which you can simplify it during renewal during renewal

For example, it may be better to put everyone

n monthly (or quarterly) doismeter reads rather
n monthly (or quarterly) doismeter reads rather

than having quarterly for some, 6 than having quarterly for some, 6-

month for

month for

thers, and monthly for the rest
thers, and monthly for the rest

Generality Generality

It’s better to be generally right than specifically

It’s better to be generally right than specifically wrong wrong

Try not to tie yourself down with needless

Try not to tie yourself down with needless specificity when a broader generality will specificity when a broader generality will accomplish the same thing accomplish the same thing p g p g

For example

For example – – say that you will package say that you will package biological wastes in accordance with waste biological wastes in accordance with waste acceptance criteria instead of promising to pack acceptance criteria instead of promising to pack in lime, freeze, double in lime, freeze, double-

bag, and surround with

bag, and surround with absorbant materials absorbant materials

Or say that you will have alpha, beta, gamma,

Or say that you will have alpha, beta, gamma, and neutron survey meters on and neutron survey meters on-

hand; but don’t

hand; but don’t list your current instrument inventory list your current instrument inventory

A “clean” license A “clean” license

Try to minimize attachments and

Try to minimize attachments and referenced materials referenced materials – – the license should the license should be as “stand be as “stand-

alone” as possible

alone” as possible F l id tt hi it F l id tt hi it

For example, avoid attaching your site

For example, avoid attaching your site- specific procedures, radiation safety specific procedures, radiation safety manual, training book, etc. to your license manual, training book, etc. to your license

Whatever materials you attach to the license

Whatever materials you attach to the license become part of your application, and you become part of your application, and you can’t change them without regulatory can’t change them without regulatory approval approval

SLIDE 41

41

Responding to radiological Responding to radiological incidents and emergencies incidents and emergencies Spills Spills

Stop spill

top spill

Warn others

arn others

Isolate the area

solate the area

Minimize exposure

inimize exposure

Stop ventilation if appropriate and possible

top ventilation if appropriate and possible

Start to clean up after immediate actions

Start to clean up after immediate actions completed completed

Stop spill Stop spill

Pick up container (if possible) and place

Pick up container (if possible) and place into bucket or deep tray into bucket or deep tray

Place absorbent materials over spilled

Place absorbent materials over spilled li id ( d t l li id ( d t l liquid (or damp paper towels or rags over liquid (or damp paper towels or rags over spilled powder) spilled powder)

Idea is to stop adding more material to

Idea is to stop adding more material to spill and to limit contaminated area spill and to limit contaminated area

Warn others Warn others

Call RSO or others who can assist

Call RSO or others who can assist

Inform others nearby

Inform others nearby

Idea is to keep unprepared people out of

Idea is to keep unprepared people out of spill area and to get help in cleaning spill spill area and to get help in cleaning spill

Isolate area Isolate area

Put up physical boundary around spill

Spill boundary should be at least 1

Spill boundary should be at least 1-

2 meters

2 meters from farthest splash if possible from farthest splash if possible

May simply close and lock door to room

ALWAYS put sign on spill boundary

Nobody should enter spill area unless dressed in

Nobody should enter spill area unless dressed in proper PPE proper PPE

Nobody should leave spill area until surveyed by

Nobody should leave spill area until surveyed by RSO or trained rad worker (including personnel RSO or trained rad worker (including personnel in area when spill occurred) in area when spill occurred)

Minimize exposure Minimize exposure

Take a short time to think through

Take a short time to think through situation situation

Make sure you are taking proper and

Make sure you are taking proper and reasonable actions reasonable actions reasonable actions reasonable actions

Make sure you know how to deal with

Make sure you know how to deal with situation situation

Most radiological incidents are not life

Most radiological incidents are not life-

endangering

endangering – – you have the luxury of you have the luxury of taking a few minutes to make sure you’re taking a few minutes to make sure you’re doing the right thing doing the right thing

SLIDE 42

42

Stop ventilation Stop ventilation

If spilled material is powdered or volatile,

If spilled material is powdered or volatile, stopping ventilation can help to reduce stopping ventilation can help to reduce spread of contamination spread of contamination p

Whether or not to try to stop ventilation is

Whether or not to try to stop ventilation is a judgment call on the part of the RSO or a judgment call on the part of the RSO or person at the scene person at the scene

Clean Clean-up up

Work from outside of spill area towards

Work from outside of spill area towards the center the center

Work from top to bottom (if appropriate)

Work from top to bottom (if appropriate)

Can usually use commercial cleaners

Can usually use commercial cleaners (Formula 409, Windex, Easy (Formula 409, Windex, Easy-

Off, etc.)

Off, etc.)

Use Radiac Wash and similar products if

Use Radiac Wash and similar products if you have radioactive metals you have radioactive metals

Monitor area periodically to ensure

Monitor area periodically to ensure cleanup efforts are effective cleanup efforts are effective

Skin contamination Skin contamination

Contact RSO immediately

Get good count rate on contaminated area

Get good count rate on contaminated area and write it down for future reference and write it down for future reference

Begin washing with mild soap and cool to

Begin washing with mild soap and cool to warm water warm water

Count area every few washes to monitor

Count area every few washes to monitor clean clean-

up progress

up progress

May need to notify state, calculate skin

May need to notify state, calculate skin dose, and/or monitor for internal exposure dose, and/or monitor for internal exposure

Skin contamination Skin contamination

The three Cs

The three Cs

C

Contact the Health and Safety Officer

ntact the Health and Safety Officer

C

Count the contaminated area with a Geiger

unt the contaminated area with a Geiger

counter and record the count rate counter and record the count rate counter and record the count rate counter and record the count rate

C

Clean the contaminated area lean the contaminated area

In this case, rapid decontamination is

In this case, rapid decontamination is important important – – should go to the nearest sink should go to the nearest sink to clean up to clean up

Skin decontamination Skin decontamination

Don’t do anything that will be painful or

Don’t do anything that will be painful or uncomfortable uncomfortable

Use mild soap and cool to warm water

Get a good count rate every few washes and

Get a good count rate every few washes and record the information to make sure that record the information to make sure that record the information to make sure that record the information to make sure that decontamination efforts are effective decontamination efforts are effective

Keep cleaning until Radiation Safety says it’s OK

Keep cleaning until Radiation Safety says it’s OK to stop, or until all elevated counts are gone to stop, or until all elevated counts are gone

Remember

Remember – – some isotopes are absorbed some isotopes are absorbed through the skin, so dropping counts may also through the skin, so dropping counts may also indicate absorption and not decontamination indicate absorption and not decontamination

Injured personnel in radiological Injured personnel in radiological incidents or emergencies incidents or emergencies

Must treat each on a case

Must treat each on a case-

by

by-

case basis

case basis

Always make emergency responders or ER

Always make emergency responders or ER personnel aware of radiological concerns personnel aware of radiological concerns

Even highly

Even highly-contaminated patients pose very little contaminated patients pose very little

Even highly

Even highly-contaminated patients pose very little contaminated patients pose very little

r no risk to emergency responders or to ER staff
r no risk to emergency responders or to ER staff

Take care of most pressing problems first

Examples:

Life

Life-

threatening injuries must be treated immediately

threatening injuries must be treated immediately

Mild injuries can sometimes wait for decontamination

Move injured personnel from dangerous radiation levels

SLIDE 43

43

High radiation levels High radiation levels

Get good dose reading in area and in

ther “populated” areas (offices, etc.)
ther “populated” areas (offices, etc.)

evacuate area if necessary

Try to determine source of radiation

Try to stop/shield source

Machines can be turned off

Sources must be either retracted or covered

Sources must be either retracted or covered with shielding such as lead with shielding such as lead

How to respond to a How to respond to a radiological emergency radiological emergency Priorities Priorities

Stay alive and healthy

Take care of victims

Take care of victims Put out fires and other emergency Put out fires and other emergency

Put out fires and other emergency

Put out fires and other emergency response work response work

Protect yourself Protect yourself

Wear proper PPE

Wear proper PPE – – including respiratory including respiratory protection protection

Wear your dosimetry (at least one person

Wear your dosimetry (at least one person y y ( p y y ( p per team) per team)

Use radiation detectors (if available)

Use radiation detectors (if available)

Use Universal Precautions when working

Use Universal Precautions when working with contaminated victims with contaminated victims

Limit stay time in dangerous areas

Limit stay time in dangerous areas

Caring for victims Caring for victims

Even highly

Even highly-

contaminated patients pose

contaminated patients pose very little or no risk to emergency very little or no risk to emergency responders or to ER staff responders or to ER staff

Take care of most pressing problems first

Take care of most pressing problems first l l

Examples:

Life

Life-

threatening injuries must be treated

threatening injuries must be treated immediately immediately

Mild injuries can sometimes wait for

Mild injuries can sometimes wait for decontamination decontamination

Move injured personnel from dangerous

Move injured personnel from dangerous radiation levels radiation levels

Contamination control Contamination control

If time and victim’s condition permit:

If time and victim’s condition permit:

Remove outer clothing

Wrap in blanket or sheet

Wrap in blanket or sheet Cover with “bunny suit” Cover with “bunny suit”

Cover with bunny suit

Wipe down with damp sponge or rag

Shower or spray with water to remove

Shower or spray with water to remove contamination contamination

Take whatever actions you can without

Take whatever actions you can without placing the patient at greater risk placing the patient at greater risk

SLIDE 44

44

Radioactive sources Radioactive sources What sources look like What sources look like

Irradiators and radiography sources Irradiators and radiography sources

Radiological terrorism Radiological terrorism Scenario 1: RDD attack Scenario 1: RDD attack

A terrorist group sets off an RDD during

A terrorist group sets off an RDD during some big event some big event

~50 people are killed by blast

~50 people are killed by blast

About 10,000 people are directly

About 10,000 people are directly

About 10,000 people are directly

About 10,000 people are directly contaminated contaminated

Plume drifts across downtown and

Plume drifts across downtown and surrounding neighborhoods surrounding neighborhoods

SLIDE 45

45

Some questions: Some questions:

What are the likely radiation effects on

What are the likely radiation effects on those in the area? those in the area?

On emergency responders?

On emergency responders? On emergency responders? On emergency responders?

So So – – is it safe? is it safe?

1000 Ci of Co

1000 Ci of Co-

60 will give a dose rate of

60 will give a dose rate of about 8 rem/hr about 8 rem/hr

Co

Co-

60 is not a huge inhalation hazard, and

60 is not a huge inhalation hazard, and plume should settle fairly quickly plume should settle fairly quickly plume should settle fairly quickly plume should settle fairly quickly

Contamination can be controlled by

Contamination can be controlled by wearing turnout gear wearing turnout gear

What about risks to the public? What about risks to the public?

Those at the scene may have heavy

Those at the scene may have heavy contamination and possible inhalation contamination and possible inhalation – – they are at the greatest risk. they are at the greatest risk. y g y g

However, many will probably have higher

However, many will probably have higher risk from injuries risk from injuries – – and serious injuries and serious injuries must be treated first must be treated first

And the emergency responders? And the emergency responders?

Heat and fatigue are probably going to

Heat and fatigue are probably going to keep an emergency responder from being keep an emergency responder from being in an area long enough to develop in an area long enough to develop g g p g g p radiation sickness radiation sickness

It will take up to 12 hours in the area in this

It will take up to 12 hours in the area in this scenario to start to get radiation sickness scenario to start to get radiation sickness

So if responders wear their PPE, they

So if responders wear their PPE, they should not be at risk should not be at risk

Scenario 2: Irradiator attack Scenario 2: Irradiator attack

A terrorist group plops a 1000 Ci Co

A terrorist group plops a 1000 Ci Co-

60

60 irradiator in a movie theater (say for a irradiator in a movie theater (say for a Lord of the Rings re Lord of the Rings re-

run)

run) g )

During the movie, some people exit the

During the movie, some people exit the theater vomiting, and others complain that theater vomiting, and others complain that there are sick and unconscious people in there are sick and unconscious people in the theater the theater

An usher found a canister beneath a seat

Same questions: Same questions:

What are the likely radiation effects on

What are the likely radiation effects on those in the area? On emergency those in the area? On emergency responders? responders? Wh t ti h ld th bli t k ? Wh t ti h ld th bli t k ?

What actions should the public take?

What actions should the public take?

SLIDE 46

46

Radiation levels Radiation levels

1 meter from source, rad levels will be

1 meter from source, rad levels will be fatal in about 45 minutes fatal in about 45 minutes

2 meters from source rad levels will fatal

2 meters from source, rad levels will fatal

2 meters from source, rad levels will fatal in 3 hours in 3 hours

10 meters from source, rad levels will take

10 meters from source, rad levels will take about 10 hours to make you sick about 10 hours to make you sick

So you can work here

So you can work here – – just wear your just wear your dosimeter dosimeter

Risk to the public Risk to the public

A 1000 Ci source in a movie theater may kill up

A 1000 Ci source in a movie theater may kill up to a dozen or so people to a dozen or so people – – assuming that assuming that everyone stays for the entire movie everyone stays for the entire movie

Up to 100 people may develop mild to severe

Up to 100 people may develop mild to severe radiation sickness over the next several weeks, radiation sickness over the next several weeks, again assuming they stay for the entire movie again assuming they stay for the entire movie

There is NO risk to anyone else because

There is NO risk to anyone else because irradiated people do not become radioactive irradiated people do not become radioactive

Risk to emergency responders Risk to emergency responders

There is NO risk to emergency responders,

There is NO risk to emergency responders, provided they heed dose limits provided they heed dose limits

Will probably have to use several teams to

Will probably have to use several teams to recover bodies of those nearest the source recover bodies of those nearest the source

Recovering the source is potentially hazardous,

Recovering the source is potentially hazardous, but can be done safely by radiation safety but can be done safely by radiation safety professionals professionals

At worst, will have to close theater for a few

At worst, will have to close theater for a few days days

When to be worried When to be worried

If radiation dose rate is greater than 10

If radiation dose rate is greater than 10 rem/hr rem/hr

If contamination levels are more than

If contamination levels are more than

If contamination levels are more than

If contamination levels are more than 100,000 cpm 100,000 cpm

If your dosimeter reads more than 3 rem

If your dosimeter reads more than 3 rem (if you are a radiation worker) or more (if you are a radiation worker) or more than 75 mr (if you’re than 75 mr (if you’re not not a radiation a radiation worker) worker)

When to leave the area right away When to leave the area right away

If radiation levels are more than 100

If radiation levels are more than 100 rem/hr or are off rem/hr or are off-

scale

scale

If contamination levels are too high to

If contamination levels are too high to register on the highest scale of the meter register on the highest scale of the meter

If you see health physicists looking scared

Nuclear Terrorism Nuclear Terrorism

SLIDE 47

47 How Likely is Nuclear Terror? How Likely is Nuclear Terror?

Nobody believes any longer that “it takes a

Nobody believes any longer that “it takes a Manhattan Project” to build a nuclear device Manhattan Project” to build a nuclear device

Given

Given 235

235U in sufficient quantity building a gun

U in sufficient quantity building a gun-

assembled device is quite straight

assembled device is quite straight-

forward

forward

bl b bl k bl b bl k

Few

Few-

man portable; mass probably < 200 kg

man portable; mass probably < 200 kg

Yield ~ 100 tons to 1 kT

Yield ~ 100 tons to 1 kT

Given plutonium, it is possible to build simpler

Given plutonium, it is possible to build simpler implosion devices than “Fat Man” implosion devices than “Fat Man”

Mass < 1000 kg

Mass < 1000 kg

Yield ~ 1 kT to 10 kT

Yield ~ 1 kT to 10 kT

Weapons can be (have been?) stolen.

Primitive and Simple Nuclear Designs are Primitive and Simple Nuclear Designs are Well Known and Generally Understood Well Known and Generally Understood

Design and Construction Design and Construction

Gun

Gun-

assembled devices

assembled devices

Extremely simple

Target bolted to gun; can’t miss

Builders will figure out the tricks along the way.

Implosion devices

Won’t use “Fatman

Won’t use “Fatman-

style lenses”

style lenses”

Will be very unpredictable/unreliable

Yield could be as high as several kT

Very, very dirty from Pu contamination

Nuclear devices Nuclear devices

Hiroshima

Hiroshima

Weapon size about 15 kT (similar to IND)

Total inhabitants, 320,081

Deaths, 122,358

Injured, 79,130

Uninjured, 118,613

Comparison with terrorist device Comparison with terrorist device

No way to predict yield

No way to predict yield – – IND may be IND may be small, while stolen weapon may be higher small, while stolen weapon may be higher

Hiroshima was an airburst, while IND

Hiroshima was an airburst, while IND would likely be a surface burst would likely be a surface burst y

Surface burst will be “dirtier” due to inclusion

f surface materials in blast
f surface materials in blast
Site of detonation will influence effects

Site of detonation will influence effects

One likely scenario would be in port facilities,

One likely scenario would be in port facilities, although small (suitcase) device, or device in although small (suitcase) device, or device in cargo container may be taken almost cargo container may be taken almost anywhere anywhere

SLIDE 48

48

Effects Effects

Blast

Radiation and fallout

Radiation and fallout – – can be fatal up to a can be fatal up to a few miles away in the plume few miles away in the plume

Thermal

Firestorm

Firestorm – – as in Dresden and Tokyo, may as in Dresden and Tokyo, may be more destructive than initial blast be more destructive than initial blast

All depend strongly on yield of device and

All depend strongly on yield of device and location of detonation location of detonation

Making or getting nuclear weapons Making or getting nuclear weapons

It’s thought that up to 40 former Soviet

It’s thought that up to 40 former Soviet “suitcase nukes” are not accounted for “suitcase nukes” are not accounted for

There are a number of research reactors

There are a number of research reactors still fueled with HEU still fueled with HEU

Pakistan offered nuclear technology to

Pakistan offered nuclear technology to many nations, including N. Korea, Iraq, many nations, including N. Korea, Iraq, and Libya and Libya – – may have sold to others, too may have sold to others, too

May be able to purchase weapons, Pu, or

May be able to purchase weapons, Pu, or HEU on nuclear black market HEU on nuclear black market

The bottom line The bottom line

It is likely that terrorist organizations are trying

It is likely that terrorist organizations are trying to obtain nuclear weapons or fissionable to obtain nuclear weapons or fissionable materials materials

There are many opportunities to obtain such

There are many opportunities to obtain such weapons weapons weapons weapons

Nuclear weapons effects, even for a “fizzle” or

Nuclear weapons effects, even for a “fizzle” or low low-

yield device, would be horrific

yield device, would be horrific

Nuclear weapons can be smuggled in cargo

Nuclear weapons can be smuggled in cargo containers or suitcases containers or suitcases – – detection is possible, detection is possible, but only if we are looking for something but only if we are looking for something

However, it is unlikely that such devices are now

However, it is unlikely that such devices are now in the possession of terrorists in the possession of terrorists

Resources Resources

Health Physics Society (

Health Physics Society (www.hps.org www.hps.org)

Including Ask the Experts feature

CDC (

CDC (http://www bt cdc gov/ http://www bt cdc gov/)

CDC (

CDC (http://www.bt.cdc.gov/ http://www.bt.cdc.gov/)

AFRRI (

AFRRI (http://www.afrri.usuhs.mil/ http://www.afrri.usuhs.mil/)

REAC/TS (

REAC/TS (http://www.orau.gov/reacts/ http://www.orau.gov/reacts/) )

Radiation Information Network

Radiation Information Network (http://www.physics.isu.edu/radinf/ http://www.physics.isu.edu/radinf/)

A few more odds and ends… A few more odds and ends… Radiological triage flowchart Radiological triage flowchart

SLIDE 49

49 Radiological area entry and exit Radiological area entry and exit point point

One way to assess dose One way to assess dose Prognosis tool Prognosis tool

Expected progression of symptoms Expected progression of symptoms

Symptoms 4 8 12 16 20 24 1 2 3 4 5 6 7 1 2 3 4 5 6 Nausea Vomiting/retching Anorexia Diarrhea/cramps Fatigue Weakness Hypotension Hours Days Weeks Dose of 0-0.75 Gy (0-75 rad) in air Time post-exposure 0-5% mild Hypotension Dizziness Disorientation Bleeding Fever Infection Ulceration Fluid loss/electrolyte imbalance Headache Fainting Prostration Death Medical treatment Clinical remarks Reassurance, counseling Possible anxiety, possible mild lymphocyte depression in 24 hrs

Symptoms 4 8 12 16 20 24 1 2 3 4 5 6 7 1 2 3 4 5 6 Nausea Vomiting/retching Anorexia Diarrhea/cramps Fatigue Weakness Hypotension Dizziness Disorientation Dose of 0.75-1.5 Gy (75-150 rad) in air 5-20% mild 15-50% mild 5-30% mild Time post-exposure Hours Days Weeks Bleeding Fever Infection Ulceration Fluid loss/electrolyte imbalance Headache Fainting Prostration Death Medical treatment Clinical remarks

B. Increased susceptibility to non-opportunistic pathogens

Debridement and primary closure of wounds, no surgery delay

A. Moderate drop in lymphocyte, platelet, granulocyte counts

B A A

SLIDE 50

50

Symptoms 4 8 12 16 20 24 1 2 3 4 5 6 7 1 2 3 4 5 6 Nausea Vomiting/retching Anorexia Diarrhea/cramps Fatigue Weakness Hypotension Dizziness Disorientation Bleeding Hours Days Weeks mild mild A 10% mild 30-60% mild-moderate 30-60% mild-moderate Dose of 1.5 - 3.0 Gy (150-300 rad) in air Time post-exposure 30-70% mild-moderate 20-70% mild-moderate 50-90% g Fever Infection Ulceration Fluid loss/electrolyte imbalance Headache Fainting Prostration Death Medical treatment Clinical remarks

B. Drop in granulocytes from 6 to 2.0-4.5 x 103 per mm3
C. Drop in lymphocytes from 3 to 1.0-2.0 x103 per mm3

C

A. Drop in platelets from 3 to 0.8-1.8 x105 per mm3

B 10-50% <5% Fluid, electrolytes for GI losses, cytokines for immune compromised Symptoms 4 8 12 16 20 24 1 2 3 4 5 6 7 1 2 3 4 5 6 Nausea Vomiting/retching Anorexia Diarrhea/cramps 10% moderate Fatigue Weakness Hypotension Dizziness Disorientation Bleeding Dose of 3.0 to 5.3 Gy (300 to 530 rad) in air Time post-exposure Hours Days Weeks 70-90% moderate 0-80% moderate 90-100% severe 60% 40-60% 60-90% moderate mild moderate moderate mild 60-90% moderate A 0-50% moderate Fever Infection Ulceration Fluid loss/electrolyte imbalance Headache Fainting Prostration Death Medical treatment Clinical remarks

B. Drop in granulocytes from 6 to 0.5-2.0 x 103 per mm3
C. Drop in lymphocytes from 3 to 0.4-1.0 x103 per mm3
D. Possible epilation

Fluid, electrolytes for GI losses, cytokines, specific antibiotics

A. Drop in platelets from 3 to 0.1-0.8 x105 per mm3

5-50% B C 80% moderate D 30% mod. Symptoms 4 8 12 16 20 24 1 2 3 4 5 6 7 1 2 3 4 5 6 Nausea Vomiting/retching Anorexia Diarrhea/cramps 10% moderate to severe Fatigue Weakness Hypotension Dizziness Disorientation Bleeding A 50-100% mod-sev Dose of 5.3 to 8.3 Gray (530-830 rad) in air Time post-exposure Hours Days Weeks 90-100% mod - severe 60-100% severe 80-100% mod-severe 100% 60-100% severe 100% 90-100% moderate to severe 90-100% moderate to severe 60% moderate 60% moderate Fever Infection Ulceration D 50% mild-mod Fluid loss/electrolyte imbalance Headache Fainting Prostration Death Medical treatment Tertiary level intensive care, cytokines, fluids, antibiotics, GI decon Clinical remarks

B. Severe granulocyte drop to 0.0-0.5 x103 per mm3

Complete surgery 36-48 C. Severe lymphocyte drop 0.0-0.1 x105 per mm3 hrs, or wait for 6 weeks

D. Epilation
E. Mild intestinal damage

50% mild-moderate 50% B 60-100% mod-severe C 40% mild to moderate E 30% 50% 60% 50-99%

A. Severe platelet drop to 0.0-0.1 x105 per mm3

Symptoms 4 8 12 16 20 24 1 2 3 4 5 6 7 1 2 3 4 5 6 Nausea Vomiting/retching Anorexia Diarrhea/cramps 10% moderate to severe 100% moderate to severe Fatigue Weakness Hypotension 100% severe Dizziness 100% severe Disorientation 100% severe Bleeding F Weeks 100% moderate to severe 100% moderate to severe 100% Dose of 8.3 to 11 Gy (830-1100 rad) in air Time post-exposure Hours Days 100% 100% 100% 100% severe 100% severe A 100% severe B 100% Fever Infection Ulceration Fluid loss/electrolyte imbalance Headache Fainting Prostration Death Medical treatment Clinical remarks

B. Granulocyte count drops to nearly 0

Bone marrow totally

C. Lymphocyte count drops to nearly 0

depleted

D. Epilation
E. Moderate intestinal damage

Supportive therapy, aggressive therapy if evidence of response

A. Platelet count drops to nearly 0

100% B 100% severe C D 100% severe 80% moderate E 80% severe 80% moderate 100% severe 80% mod to severe Symptoms 4 8 12 16 20 24 1 2 3 4 5 6 7 1 2 3 4 5 6 Nausea 100% moderate-severe Vomiting/retching 100% mod-severe Anorexia Diarrhea/cramps 10% severe Fatigue Weakness Hypotension Dizziness 100% severe Disorientation 100% severe Bleeding B 100% severe Dose 11-15 Gray (1100-1500 rad) in air Time post-exposure Hours Days Weeks 100% severe 100% severe 100% severe 100% severe 100% severe 100% severe 100% severe 100% severe A 80% mild 100% severe 100% severe Bleeding B 100% severe Fever Infection Ulceration Fluid loss/electrolyte imbalance Headache 100% moderate to severe Fainting Prostration Death Medical treatment Clinical remarks

B. Platelet, lymphocyte, granulocyte counts drop to 0
C. Epilation
D. Moderate to severe intestinal damage

D 100% severe Bone marrow totally depleted, tertiary care may help somewhat

A. Blood press drops 25%, temp increases to 102 F

B 100% severe B C 100% severe 100% moderate to severe 100% severe 70% mod-severe 70% mod-severe 100% Symptoms 4 8 12 16 20 24 1 2 3 4 5 6 7 1 2 3 4 5 6 Nausea Vomiting/retching Anorexia Diarrhea/cramps 20% severe Fatigue Weakness Hypotension Dizziness Disorientation Bleeding A 100% severe Dose of 15-30 Gray (1500-3000 rad) in air Time post-exposure Hours Days Weeks 100% severe 100% severe 100% severe 100% severe 100% severe 100% severe 100% severe 100% severe 100% severe 100% moderate to severe 100% severe 100% severe Fever Infection Ulceration Fluid loss/electrolyte imbalance Headache Fainting Prostration Death Medical treatment Clinical remarks B Severe intestinal damage Bone marrow completely C Renal failure depleted within days. Supportive therapy A Platelet, granulocyte, lymphocyte counts drop to 0 C 100% 45-80% mod-severe B 100% moderate to severe 100% severe 80% severe 80% severe 80% severe A 100% severe A 100% severe

SLIDE 51

51

Lymphocyte depletion Lymphocyte depletion Case studies Case studies Problem 1: Spill Problem 1: Spill

Technician calls to tell you about a spill.

Technician calls to tell you about a spill. He claims to have readings of 20 mr/hr on He claims to have readings of 20 mr/hr on a GM counter a meter above a spill of Tc a GM counter a meter above a spill of Tc-

99

(10 Ci) 99 (10 Ci) 99m (10 mCi). 99m (10 mCi).

Is this reading reasonable?

How do you confirm your answer above?

What equipment do you bring to the spill?

How do you deal with the incident?

Problem 2: Refractory brick Problem 2: Refractory brick

A load of brick from your furnace trips a

A load of brick from your furnace trips a landfill radiation alarm. landfill radiation alarm.

Why does this happen?

Why does this happen? y pp y pp

What do you do with the brick?

What do you do with the brick?

What sort of risk do your employees face

What sort of risk do your employees face from the radiation? from the radiation?

Do you have to get a license and train

Do you have to get a license and train your employees as radiation workers? your employees as radiation workers?

Problem 3: Landfill alarm Problem 3: Landfill alarm

A load of residential waste sets off a

A load of residential waste sets off a landfill radiation portal monitor. The “hot” landfill radiation portal monitor. The “hot” waste is traced to a nuclear medicine waste is traced to a nuclear medicine ti t f h it l ti t f h it l patient from your hospital. patient from your hospital.

What do you do with the waste?

What instruments would you take to the

What instruments would you take to the landfill? landfill?

Are you responsible for the patient’s

Are you responsible for the patient’s waste? waste?

Problem 4: High badge readings Problem 4: High badge readings

An employees badge reads 53 rem one

An employees badge reads 53 rem one

month. The employee did nothing
month. The employee did nothing

different compared to other months. different compared to other months. p p

How can you confirm or reject this

How can you confirm or reject this reading? reading?

What actions do you need to take?

What actions do you need to take?

SLIDE 52

52

Licensing exercise Licensing exercise For the exercise For the exercise

Break into groups of 5 or so

Break into groups of 5 or so

Draw up a brief description of a license

Draw up a brief description of a license application that addresses the questions application that addresses the questions application that addresses the questions application that addresses the questions

n the following slide
n the following slide
Include sketches as necessary and

Include sketches as necessary and appropriate appropriate

Irradiator license application Irradiator license application

You want to get a license for a 500 Ci Co

You want to get a license for a 500 Ci Co-

60

60 research irradiator. research irradiator.

What instrumentation do you need for surveys?

Where in your building should the irradiator be

Where in your building should the irradiator be placed? placed? placed? placed?

What topics should you include in your training?

Who should receive dosimetry? Do you need

Who should receive dosimetry? Do you need any other dosimeters? any other dosimeters?

How do you leak test this source?

How do you return a spent source to the

How do you return a spent source to the vendor? vendor?

Closing thoughts Closing thoughts Health risks Health risks

At levels allowed by regulations, radiation

At levels allowed by regulations, radiation is not harmful is not harmful

In most cases radiological risks can be

In most cases, radiological risks can be

In most cases, radiological risks can be readily managed and reduced readily managed and reduced

Many activities (e.g. driving, some sports)

Many activities (e.g. driving, some sports) are much more dangerous are much more dangerous

Legal risks Legal risks

Nevertheless, it is possible to be sued over

Nevertheless, it is possible to be sued over radiation radiation-

induced illness, even if the

induced illness, even if the probability of causation is very low probability of causation is very low p y y p y y

For this reason, personnel monitoring and

For this reason, personnel monitoring and radiological survey records (and radiological survey records (and instrument maintenance records) are instrument maintenance records) are essential documents essential documents

SLIDE 53

53

RSO’s role RSO’s role

The RSO is the single person most

The RSO is the single person most responsible for maintaining a safe and responsible for maintaining a safe and legal radiation safety program legal radiation safety program

Most people in the organization will look

Most people in the organization will look to the RSO for information and advice to the RSO for information and advice

Don’t give out erroneous information

Don’t give out erroneous information – – if if you don’t know the answer, look it up or you don’t know the answer, look it up or ask someone for assistance ask someone for assistance

If you have any questions: If you have any questions:

E mail me at mail me at paksbi@rit edu paksbi@rit edu

E-mail me at

mail me at paksbi@rit.edu paksbi@rit.edu

Check out the HPS web site at

Check out the HPS web site at www.hps.org www.hps.org

Bonus Materials Bonus Materials How uranium enrichment How uranium enrichment works works Uranium enrichments Uranium enrichments

Natural U

Natural U – – 99.2% U 99.2% U-

238, 0.72% U

238, 0.72% U-

235

235

Enriched U

Enriched U -

>1% U

>1% U-

235

235 Reactors Reactors 3 8% 8%

Reactors

Reactors – 3-8% 8%

Research reactors

Research reactors – – 20% 20%

Weapons

Weapons – – 90+% 90+%

SLIDE 54

54

Communicating with the Communicating with the Media and the Public Media and the Public

There is a tendency to assume that reporters There is a tendency to assume that reporters either can’t understand technical issues, is either can’t understand technical issues, is not interested in technical issues, or has not interested in technical issues, or has already made up its mind. This is not always already made up its mind. This is not always the case and we should generally treat them the case and we should generally treat them the case, and we should generally treat them the case, and we should generally treat them as willing and able to learn about issues of as willing and able to learn about issues of

importance. Anyone who picks up the phone
importance. Anyone who picks up the phone

to call has already made an effort to learn to call has already made an effort to learn something something – – we must respect that effort. we must respect that effort.

Questions to consider Questions to consider

What prompted the communication in

What prompted the communication in the first place? the first place?

Who are you talking to?

What information is the other person

What information is the other person looking for? looking for?

What information do you want to

What information do you want to convey? convey?

Is this an opportunity to get any

ther information across?
ther information across?

What prompted the communication What prompted the communication in the first place? in the first place?

News story

News story

Nuclear power

Radioactive waste

Radioactive waste Radiological terrorism Radiological terrorism

Radiological terrorism

Nuclear proliferation

Exposure to radiation (to the person

Exposure to radiation (to the person calling or to a family member) calling or to a family member)

Medical problem thought to be linked

Medical problem thought to be linked to previous radiation exposure to previous radiation exposure

Who are you talking with? Who are you talking with?

An experienced science writer

A junior reporter

What “beat”? Science, environment,

What “beat”? Science, environment, political city national etc ? political city national etc ? political, city, national, etc.? political, city, national, etc.?

Someone trained in science, or some

ther field?
ther field?

What information do you want to convey? What information do you want to convey?

Salient points about radiation

High levels of radiation can be harmful

The risks of exposure to low levels of radiation are

The risks of exposure to low levels of radiation are typically over typically over-

stated

stated

Radiation is a weak carcinogen and very poor at

Radiation is a weak carcinogen and very poor at i d i d ti ff t i d i d ti ff t inducing reproductive effects inducing reproductive effects

Salient points about the matter at hand

Evaluate dose calculations (if applicable)

Compare calculated dose with those required to

Compare calculated dose with those required to produce effects produce effects

Is dose less than 10 rem? If so, refer to HPS position

Is dose less than 10 rem? If so, refer to HPS position paper regarding low paper regarding low-

dose risks

dose risks

SLIDE 55

55 Is this an opportunity to get any Is this an opportunity to get any

ther information across?
ther information across?

Radiation is a natural part of the

Radiation is a natural part of the environment and varies widely around environment and varies widely around the world the world

HPS and ICRP have both advised

HPS and ICRP have both advised against calculating risk from low doses against calculating risk from low doses

f radiation
f radiation

We have over a century of experience

We have over a century of experience working with radiation and know a working with radiation and know a great deal about its biological and great deal about its biological and medical effects medical effects Don’t try to sugarcoat the issues; if there are Don’t try to sugarcoat the issues; if there are negative aspects to the story or question, negative aspects to the story or question, acknowledge this. But don’t be afraid to acknowledge this. But don’t be afraid to point out that the negative is not as bad as point out that the negative is not as bad as many would lead us to believe We “win” if many would lead us to believe We “win” if many would lead us to believe. We win if many would lead us to believe. We win if the end result is someone with accurate the end result is someone with accurate information and the inclination to call us back information and the inclination to call us back in the future. We lose if we are seen as in the future. We lose if we are seen as being as biased as the “antis”. being as biased as the “antis”.

What is the media after? What is the media after?

Accurate information

The most important relevant facts

The most important relevant facts A good story that educates readers A good story that educates readers

A good story that educates readers

Increased readership, viewers, listeners

Balance

Background information (if time permits)

General rules General rules

Only talk about things you know about

Only talk about things you know about

Don’t be patronizing or condescending

Don’t be patronizing or condescending

Leave yourself enough time to review

Leave yourself enough time to review background information background information – don’t rush the don’t rush the g interview interview

Assume

Assume anything anything you say may be quoted you say may be quoted

Be ready to refer reporter on to other HPs

Be ready to refer reporter on to other HPs who may know more about the subject who may know more about the subject matter matter

Time is Time is always always an issue an issue

All

All reporters have deadlines to meet reporters have deadlines to meet

Reporters’ deadlines are usually fixed

Reporters’ deadlines are usually fixed and unchangeable and unchangeable

If a reporter can’t talk with you and meet

If a reporter can’t talk with you and meet their deadline, they’ll go to press without their deadline, they’ll go to press without your information your information

Non

Non-

reporters (i.e. the curious public) is

reporters (i.e. the curious public) is important, too important, too – – don’t make them wait don’t make them wait

either. Something prompted their call,
either. Something prompted their call,

and they deserve a timely response. and they deserve a timely response.

Don’t be afraid to say “I Don’t be afraid to say “I don’t know” if appropriate. don’t know” if appropriate. Hopefully this will be Hopefully this will be f ll d b “I k h f ll d b “I k h followed by “I know who can followed by “I know who can help you.” or “Let me find help you.” or “Let me find

ut and I’ll get back to you.”
ut and I’ll get back to you.”

SLIDE 56

56

Accurate information Accurate information

In my experience, the vast majority of

In my experience, the vast majority of reporters want accurate information reporters want accurate information

Only a few reporters are out to confirm

Only a few reporters are out to confirm their preconceptions their preconceptions E h t h th d E h t h th d

Each reporter can reach thousands or even

Each reporter can reach thousands or even millions of people with their stories millions of people with their stories – – by by talking with reporters, you are talking to talking with reporters, you are talking to the public too the public too

We do everyone a disservice if the

We do everyone a disservice if the information we convey is not accurate information we convey is not accurate

A good story: A good story:

Sheds light on a topic of interest or

Sheds light on a topic of interest or importance importance

Helps the public make informed decisions

Helps the public make informed decisions about some matter about some matter Helps decision Helps decision makers better understand makers better understand

Helps decision

Helps decision-makers better understand makers better understand the issues at stake the issues at stake

Helps sell the media to the public (i.e. more

Helps sell the media to the public (i.e. more newspapers, more viewers, more listeners, newspapers, more viewers, more listeners, etc.) etc.)

May provide a different way of looking at an

May provide a different way of looking at an issue issue

A balanced story A balanced story

Has information from all sides of an issue

May not give

May not give equal equal weight to all sides, but weight to all sides, but tries to give tries to give appropriate appropriate weight to all sides weight to all sides tries to give tries to give appropriate appropriate weight to all sides weight to all sides

Makes an effort to let the readers decide,

Makes an effort to let the readers decide, based on the facts presented based on the facts presented

There is a tendency to be suspicious of There is a tendency to be suspicious of the media and to assume they will the media and to assume they will distort information to support their pre distort information to support their pre-

conceived notions or to sell more

conceived notions or to sell more

papers. This is sometimes the case,
papers. This is sometimes the case,

but most reporters honestly want to but most reporters honestly want to write a good, accurate story. write a good, accurate story.

Breaking news: Breaking news:

When something is unfolding, there

When something is unfolding, there may be only a little time to try to may be only a little time to try to work with either the public or the work with either the public or the media media media media

Examples:

Tokaimura

Arrest of dirty bomb suspect

Kursk sinking

Any actual future radiological or nuclear

Any actual future radiological or nuclear attack, incident, or emergency attack, incident, or emergency

In a breaking story: In a breaking story:

Reporters generally have a higher sense of

Reporters generally have a higher sense of urgency urgency

There may not be time to go into much

There may not be time to go into much

There may not be time to go into much

There may not be time to go into much background information background information

It’s best to stick to the most pertinent

It’s best to stick to the most pertinent facts regarding the story and radiation in facts regarding the story and radiation in general general

SLIDE 57

57 I take the approach that the reporter I take the approach that the reporter is doing me a favor by giving me the is doing me a favor by giving me the

pportunity to present the public
pportunity to present the public

with good information. That means with good information. That means that I expect to work with the that I expect to work with the i t i t t th f b i t i t t th f b interviewer to return the favor by interviewer to return the favor by helping set up interview times, helping set up interview times, locations, or settings that will make locations, or settings that will make the interview convenient and the interview convenient and valuable for the crew. valuable for the crew.

Example: Dirty bombs Example: Dirty bombs

Background information

Radiological versus nuclear weapons

LNT debate

Natural background exposure levels

Pertinent information

Immediate actions Immediate actions go inside not to car go inside not to car

Immediate actions

Immediate actions – go inside, not to car go inside, not to car

Not radiologically dangerous

Contaminated patients no risk to doctors

Ancillary information

Contamination vs. dose

HPS position paper on low

HPS position paper on low-

dose risk

dose risk

Detecting radiation and contamination

Results of calculations (if you have any)

Example: Fetal radiation exposure Example: Fetal radiation exposure

Background information

Where fetal exposure comes from

Regulatory dose limits

We have a century of information about

We have a century of information about radiation health effects radiation health effects

Pertinent information

It takes at least 5 rem to harm a fetus

Unless there are multiple CT scans or a lot of

Unless there are multiple CT scans or a lot of fluoroscopy, chances are that there will be no fluoroscopy, chances are that there will be no harm harm

Ancillary information

There is a background rate of birth defects and

There is a background rate of birth defects and miscarriage for everyone miscarriage for everyone

Example: Nuclear war in South Asia Example: Nuclear war in South Asia

Background information

What is a nuclear weapon and how does it work?

What effects have been noted in the past?

Pertinent information

US not likely to have any health effects from

US not likely to have any health effects from nuclear war in Asia nuclear war in Asia

Limited nuclear war, although horrible, will not

Limited nuclear war, although horrible, will not end civilization end civilization

Ancillary information

How can we detect nuclear weapons or weapons

How can we detect nuclear weapons or weapons testing? testing?

How can someone make a nuclear weapon?

Talking on radio Talking on radio

Try to speak slowly and distinctly so it’s easy to

Try to speak slowly and distinctly so it’s easy to understand you understand you

Use analogies if possible and appropriate

Try to create a picture in the listeners’ minds

Avoid jargon and technical terminology except

Avoid jargon and technical terminology except when absolutely necessary (and then explain when absolutely necessary (and then explain when absolutely necessary (and then explain when absolutely necessary (and then explain the terms) the terms)

Simplify as much as possible, but not to the

Simplify as much as possible, but not to the point of being patronizing, condescending, or point of being patronizing, condescending, or being unable to support your main points being unable to support your main points

Don’t be afraid to ask the interviewer for tips on

Don’t be afraid to ask the interviewer for tips on how to make sure their audience will get what how to make sure their audience will get what you’re trying to say you’re trying to say

TV interviews TV interviews

Dress comfortably and professionally

Dress comfortably and professionally

Don’t move too quickly

Don’t move too quickly

Look wherever the interviewer or camera

Look wherever the interviewer or camera person tells you to look person tells you to look – – usually NOT at usually NOT at h the camera the camera

If you give demonstrations, keep them

If you give demonstrations, keep them simple, easy to follow, and easy to simple, easy to follow, and easy to understand understand

Ask about props (i.e. meters) or preferred

Ask about props (i.e. meters) or preferred locations for filming locations for filming

SLIDE 58

58 Some common comments and rebuttals Some common comments and rebuttals

You can’t put a value on human life.

Do you have a life insurance policy? Medical insurance?

Risks from driving and working are voluntary and

Risks from driving and working are voluntary and controllable. controllable.

How do you get to the store? Can you control the

How do you get to the store? Can you control the drunk/teenage/distracted idiot in the car next to yours? drunk/teenage/distracted idiot in the car next to yours?

We don’t know enough about the effects of

We don’t know enough about the effects of radiation radiation

We’ve been working with radiation for over a century

We’ve been working with radiation for over a century – – far longer than almost any other harmful agent. We far longer than almost any other harmful agent. We know a LOT about the effects of radiation, especially know a LOT about the effects of radiation, especially compared to most toxins or carcinogens compared to most toxins or carcinogens

Cancer rates are going up because of radiation radiation

100 years ago the average person lived for 40

100 years ago the average person lived for 40 l d l d

years. How many people 40 and younger get
years. How many people 40 and younger get

cancer? cancer?

There is no “safe” level of radiation

There is no “safe” level of radiation exposure. exposure.

Define “safe”

Define “safe” – – low levels of radiation are no low levels of radiation are no more dangerous than driving, working, or more dangerous than driving, working, or eating fast food eating fast food

Summary Summary

We have an obligation to share accurate

We have an obligation to share accurate information with the public, either directly information with the public, either directly

r through members of the media
r through members of the media

We have an obligation to make sure our

We have an obligation to make sure our i f i i i f i i information is correct information is correct

This need not be a stressful or adversarial

This need not be a stressful or adversarial process process

Our profession can gain much from this