SLIDE 1 Natural Refrigerants Natural Refrigerants ‐ Natural Refrigerants Natural Refrigerants Safe Efficient and Reliable Use Safe Efficient and Reliable Use Safe, Efficient and Reliable Use Safe, Efficient and Reliable Use as Alternatives to HFC as Alternatives to HFC
Workshop on High Ambient Temperature, Dubai 31/10/2015 Workshop on High Ambient Temperature, Dubai 31/10/2015
- Dr. Daniel Colbourne,
- Dr. Daniel Colbourne,
Juergen Usinger Juergen Usinger
Commissioned by Commissioned by
GIZ Proklima GIZ Proklima GIZ Proklima GIZ Proklima
SLIDE 2
Table of Content Introduction Performance of AC at high ambient f f g Product Safety Assessment Production Production Infrastructure After Sales (Examples from other sectors)
SLIDE 3 INTRODUCTION
- Natural refrigerants (NR) such as Ammonia, Hydrocarbons,
CO2 are increasingly used to replace substances with high GWP such as R410A R407C R32 because of the improved GWP such as R410A, R407C, R32, because of the improved performance of NR, specifically with regard to the higher energy efficiency
- Key issues in the transition to NR are the development of
− design and production capacities of manufacturers − adequate standards that reflect state of the art − reliable infrastructures for quality services and supplies
SLIDE 4
PERFORMANCE OF AC AT HIGH AMBIENT IN INDIA
SLIDE 5
Example: India
At least two enterprises develop ACs using HC‐290 AC market in India AC market in India ‐ 2012 annual AC production about 10.5 m; demand now about 4 m/year ‐ Annual growth rate ~10% ‐ 1/5th for window units, remainder for split ACs ‐ 95% of the market is “1TR” (~3.5 kW) and “1.5TR” (~5.0 kW) ‐ Climate regions range from temperate to very Climate regions range from temperate to very high ambient
SLIDE 6 Example: Production and Distribution of HC AC in India
Model Cooling capacity COP (EER) 2013 star rating Charge size
Production and Distribution of HC‐AC in India
GSC 12 FG 7 WMG 3375 W (“1TR”) 3.72 7‐star 0.31 kg GSC 18 FG 7 WMG 5000 W (“1.5TR”) 3.72 7‐star 0.36 kg GSC 18 FG 5 WMG 5000 W (“1.5TR”) 3.45 5‐star 0.36 kg
Extensive work carried
previously to
p y p efficiency and minimise refrigerant charge; see Devotta/Padalkar et al
SLIDE 7 RESULTS: RELATIVE CAPACITY, COP, PRESSURE RATIO, DISCHARGE TEMPERATURE
80% 100% [%] HC‐290 HCFC‐22 80% 100% %] HC‐290 HCFC‐22
No performance degradation vs R22
20% 40% 60% Relative capacity 20% 40% 60% Relative COP [% 0% 20% 48 50 52 Ambient temperature [°C] R 0% 20% 48 50 52 Ambient temperature [°C] 3 4 5 io [‐] HC‐290 HCFC‐22
90 110 [°C] HC‐290 HCFC‐22
Improved working conditions vs R22
1 2 3 Compression rat 70 Discharge temp 35 48 50 52 Ambient temperature [deg C] C 50 35 48 50 52 Ambient temperature [°C]
SLIDE 8 TEWI Comparison
Model Qe EER Ref Model A 5050 W 3.51 HCFC‐22 Model B 5300 W 3.58 HCFC‐22
Comparison of TEWI and efficiency against
5300 3 58 Model C 5200 W 3.55 R‐410A Model D 5275 W 3.60 R‐410A Model E 5200 W 3.60 HFC‐32
equivalent products
15 power refrigerant
3.70 3.75 1.5TR '7-star'
10 WI [tCO2-eq]
3.60 3.65 y (EER) [W/W] Model B Model D Model E
5 TEW
3.45 3.50 3.55 Efficiency Model A Model B Model C
1.5TR, 5-star 1.5TR, 7-star Model A Model B Model C Model D Model E
3.40 4 5 6 7 8 9 10 Specific cooling cost [Rs/W] 1.5TR '5-star'
SLIDE 9 Cycle performance and system efficiency of Split AC Cycle performance and system efficiency of Split AC
In many regions performance at high ambient conditions very important:
- Test results for split air conditioner
at high outdoor temps
- R290 and R22 performance very
R290 and R22 performance very close, but R410A and R32 drop off
Source: Chen Zhen Hua, GMCC R&D Centre, China
SLIDE 10
Several manufacturers in
Other Air conditioners using R290
Several manufacturers in Europe, China, India, Australia primarily using R290 Charge sizes up to 1 kg/7 kW cooling capacity
―Very high efficiency ―Very high efficiency
Reversible systems available Major shift to R290 underway j y in China
―Availability will improve over time
SLIDE 11 R290 production capacity for RAC in China
321,000 1,430,000 1,732,000 529,000 329,000 360,000 1,507,000
Source: MEP‐
, 316,000 61,000
Source: MEP FECO/CHEAA, 2013
SLIDE 12 Ai di i li Air conditioners – split type
Gree products
―Several models developed
―Split, window, portable ―Reversible and cooling only ―Products have safety system integrated to reduce leak amount ―Lower cost than equivalent R22, R410A d l models
Capacity EER Charge Max Dimensions (mm) (kW) (W/W) (g) noise ID/OD (dB) 2 7 3 55 265 38/52 d 830×284×205 2.7 3.55 265 38/52 Indoor 830×284×205 Outdoor 760×257×541 3.5 3.52 330 41/52
SLIDE 13 Air conditioners – split type
Mid d Midea products
− Currently two sizes developed − Both reversible − Other products developed − Safety systems under development
Model Indoor unit (mm) Outdoor unit (mm) Cooling capacity EER Heating capacity COP R290 charge KFR‐ 850 × 275 780 × 540 26GW/N7 Y‐Y(C4)
× 160 × 250
2.6 kW 3.4 2.8 kW 3.6 290 g KFR‐ 35GW/N7 900 × 285
× 160
780 × 540
× 250
3 kW 3 4 3 kW 3 6 3 0 35GW/N7 Y‐Y(C4)
× 160 × 250
3.5 kW 3.4 3.7 kW 3.6 350 g
SLIDE 14
Air conditioners – split type
Benson air conditioning
Si l li l ibl d h li
p yp
―Single cooling‐only, reversible and heat‐ recovery splits
Safety aspects
―Designed to AS/NZS 1677 (similar to EN 378) ―Charge size up to 1000 g of R290
Cost of R290 systems less than R410A Efficiency (cooling and heating) better than Efficiency (cooling and heating) better than competing R410A and R22 products
SLIDE 15
Ease of application of natural refrigerants
SLIDE 16
PRODUCT SAFETY ASSESSMENT PRODUCT SAFETY ASSESSMENT FOR AC WITH HC
SLIDE 17
Safe design with flammable refrigerats: Safety standards
Relevant standards
EN 378: 2008 IEC & EN 60335 2 40 IEC & EN 60335‐2‐40 IEC & EN 60335‐2‐89
Within the USA, there are , similar standards
UL471 UL484 ASHRAE‐15 (comparable in scope to EN 378) scope to EN 378)
Also draft ISO 5149…
SLIDE 18
Safety with flammability: Other safety features
SLIDE 19 O S SS SS PRODUCT SAFETY ASSESSMENT
Quantitative risk assessment
- Operation: on 12% of time, IDU airflow on 26%; include operating faults
- Sources of ignition: In room ~4 arcs/sparks per m2 per 24 h + continuous SOI
(candle) for 1 h /24 h; non‐HC outdoor unit (20 arcs per 24 h) and cigarettes; (candle) for 1 h /24 h; non HC outdoor unit (20 arcs per 24 h) and cigarettes; electrical faults inside ODU and IDU; technicians replace faulty protected components with SOIs
12 kW unit with additional
Model
1TR
1 5TR 12 kW
Flammable quantities: volumes, mass, times were modelled for the various leak sizes, into the rooms, Scenarios: safety measures
Model
1TR
1.5TR 12 kW Load 350 W/m2 170 W/m2 240 W/m2 Piping 15 m 15 m 15 m
IDU, ODU and outside
- Leakage: annual leak rate
15%; frequency from
Charge 0.35 kg 0.42 kg 0.75 kg Room 10 m2 30 m2 50 m2 Persons 2 6 10
q y supermarkets; overall 7×10‐4 per year;
SLIDE 20 PRODUCT SAFETY ASSESSMENT
Quantitative risk assessment
Safety valve limits amount of gas that can leak into room
Risk measure
1TR
1.5TR 12 kW
Quantitative risk assessment
Ign freq (room, unit off) (/y) 5.0E‐10 3.4E‐09 6.4E‐10 Ign freq (room, unit on) (/y) 1.3E‐10 1.5E‐10 2.1E‐10 Ign freq (IDU) (/y) 1 5E 16 1 2E 16 8 8E 17
Risk of ignition is >10,000 times lower than b k d i k
Ign freq (IDU) (/y) 1.5E‐16 1.2E‐16 8.8E‐17 Ign freq (ODU) (/y) 4.3E‐13 6.3E‐13 6.3E‐13 Ign freq (outside) (/y) 1.7E‐10 2.2E‐10 4.5E‐10
background risk
g eq (outs de) (/y) . . .5 Total ignition freq (/y) 8.0E‐10 3.8E‐9 1.3E‐9 Freq secondary fire (/y) 8E‐11 4E‐10 2E‐10
Background fire frequency (USA)
b k d
Max overpressure (kPa) 5.8 6.0 6.7
Can break windows
instant 3.0 mm leak hole in IDU!
SLIDE 21
PRODUCTION CONVERSION PRODUCTION CONVERSION FOR AC WITH HC
SLIDE 22 PRODUCTION DESIGN
d / Requirements under Atex/EN 1127
SLIDE 23 Appropriate equipment used for production
PRODUCTION LINE CONVERSION
- Refrigerant storage and feeding system *
- Evacuation lines
- Strength pressure test and tightness test
- Refrigerant charging equipment *
- Performance and electrical test
Performance and electrical test equipment
- Repair area *
- A safety monitoring, alarm
and ventilation system * * Equipment and installation also conform to Atex
SLIDE 24 INFRASTRUCTURE
- Installation/servicing by non‐
competent technicians major concern – critical to implement (finance‐ based) incentive schemes )
- Sales and supply in case of AC
— “Mandatory” free installation — Free warrantee (1 – 5 years) is void if non‐certified technician interferes — Disposal covered by “E‐waste” legislation (producer take‐back scheme) — Sales staff and technicians check installation details (room size, charge size pipe length etc) size, pipe length, etc) — All details recorded in database
- Technicians must competent in
handling HCs
— Recruited through an examination, Recruited through an examination, subject to ranking scheme — Assessment & experience lead to higher ranking — High ranking technicians have HC training – those which pass are training those which pass are registered to handle HC — ~800 qualified to handle HC countrywide — Issued with appropriate tooling
SLIDE 25
SERVICE AND MAINTENANCE
SLIDE 26 SERVICE AND MAINTENANCE
Summary of risk measures compared against values based for y p g “negligible” limits for worker (from UKG HSE)
Si ifi tl l th i k f i j f l ( fl bl )
- Significantly lower than risk of injury from usual (non‐flammable)
refrigeration practice
- Nevertheless, highlights importance for training
- No notable variation within the range of charge sizes (250 – 750 g)
Risk measure Untrained/ no competence Good practice Limit service workers (HSE) competence workers (HSE) Total ignition freq (per visit) 1×10‐4 7×10‐6 < 5×10‐4 (per million; begin servicing) 106 7 500 Max overpressure (kPa) ~0 ~0 < 250 Max overpressure (kPa) < 250 Max thermal int (s (kW m‐2)4/3) 182 182 < 1000
SLIDE 27 SERVICE AND MAINTENANCE SERVICE AND MAINTENANCE
Quantitative risk assessment – extensively l t ll l t d
Preparation Opening system
evaluate all related procedures for different Service and Maintenance activities
Strength pressure test Remove refrigerant Break into system Charge refrigerant Close system Leak tightness test
SLIDE 28
FINAL REMARKS
SLIDE 29 Summary: Production and Distribution of HC‐AC in India Summary: Production and Distribution of HC‐AC in India
- So far more than 100,000 HC‐290 split ACs introduced in India, Distribution in other
countries has just started (China, Australia, Europe)
i hi t f db k lit d t b d f t l i i li hi h
- Service history, feedback, quality database and safety analysis implies high success
- General, use of HCs
− Impose new responsibilities on manufacturers for safe production practices Requires additions and changes to the existing production processes − Requires additions and changes to the existing production processes − Products must be designed for safety, capacity and efficiency − Infrastructure must be established to ensure safe environment − Re‐training of technicians must be concurrent with development processes g p p
- Safety issues related to high ambient
− Flammability risk is extremely low; >10,000 times below background fire risk − Risk to service and maintenance technicians is a concern but still comparatively low to other acceptable risks
- Compared to competing products, HC‐290 has lower TEWI, low‐ to medium cost (per
kW) and higher efficiency A ti iti i t d th f d t
- Activities are ongoing to expand the range of products
- Developments include designs for greater integrated safety to further improve
intrinsic safety of systems
SLIDE 30 FINAL REMARKS
Current status of R290 100000 ACs in the field
Dents, other external
- From the quality database, main problems identified
A fault rate of <0.5% per year implies excellent level of safety and general
Compressors (at commissioning) , damage
excellent level of safety and general reliability
Cooling complaints Electrical faults (fan motors, circuit boards)
Leak rate < 0.3% is extremely low (typically 10 – 15% for Article 5
Leakage Cooling complaints
countries) Zero leaks from the IDU or IDU connecting
50 100 150 200 250 300 350 Number of faults
IDU or IDU connecting joint
SLIDE 31 FINAL REMARKS
B d SAC d i l Based on new SAC designs – low charge, high efficiency products, most applications achieved
Refrigerant charge compared to value in
- bstructive AC standard (under review)
1000 1200 Max charge Equiv safety
/
Higher capacities in larger spaces
800 arge [g] Add meas
250 W/m2 200 W/m2
larger spaces resolved through additional
400 600 R290 cha
150 W/m2 100 W/m2
additional measures
200
Cases in the risk assessment
10 20 30 40 50 60 70 Room area [m2]
assessment
SLIDE 32 El t f UK l Elements of UK proposal
Releasable charge:
600 800 1000 t charge [g]
Releasable charge:
Additional charge permitted, if d t t d it t l k t
200 400 Refrigeran
demonstrated it cannot leak out
system off system on sys on; check temp; shut valve sys off; shut valve sys on; gas detector; shut valve leaked not leaked
valve in suction line indoor unit (e.g., evaporator) valve in suction line solenoid valve in liquid line
SLIDE 33 Measures for ensuring reduced leakage
standard
Elements of UK proposal
f g g
- Strength pressure test (mandatory)
- Leak tightness test (mandatory)
M h i l i t t t standard ⎯ Mechanical impact test ⎯ Vibration (transport) test ⎯ Resonance test C li ⎯ Cycling test ⎯ Drop test (with/out packaging) ⎯ Conformity to tightness standard Improved leak tightness ⎯ Corrosion (salt spray) test ⎯ Components & joints to ISO 14903 ⎯ Additional design/construction tightness features (prevention of frost damage,
thermal cycling, etc)
SLIDE 34 Good Prospects for Natural refrigerants Good Prospects for Natural refrigerants ..... how to proceed
- Build risk awareness in the market and explain the difference between
perceived and actual risk using a product
- Explain complexities associated with manufacturing and marketing of the
- Explain complexities associated with manufacturing and marketing of the
products of new versus the old refrigerants
- Develop competence of market actors in safe adoption and supply of new
technologies and products and create competitive environment
- Implement awareness, training and certification to build capacity and
competence in developing new products and qualified services p p g p q
- Develop or adapt the quality of technical standards for products and services
- Adjust or put new incentives and regulation in place, including bans, taxes,
t f t d t d d b id li i i th t agreements, safety norms and standards, subsidy policies in the energy sector 03.11.2015 34
SLIDE 35
Thank you for your attention Thank you for your attention
SLIDE 36
APPLICATION OF NATURAL REFRIGERANTS APPLICATION OF NATURAL REFRIGERANTS IN OTHER FIELDS
SLIDE 37 Comparison of energy consumption Comparison of energy consumption
Source: Danfoss, 2013
SLIDE 38
Existing chillers with natural refrigerants Existing chillers with natural refrigerants
SLIDE 39 Plug‐in chillers and freezers
Many commercial cabinets with R290, R1270, R600a
Plug‐in chillers and freezers
R290, R1270, R600a
―End users report 5 – 15% lower energy use
Numerous manufacturers within Numerous manufacturers within Europe, Japan, Central America, Southern Africa, China, SE Asia, etc Two general categories Two general categories
―Movable type appliances with charges up to 150 g ―Fixed appliances charges up to 1.5 kg Fixed appliances charges up to 1.5 kg
SLIDE 40 HC hill
Several manufacturers using HCs
Benson Bright Earthcare Frigadon Futron
HC chillers
―Benson, Bright, Earthcare, Frigadon, Futron, Klima‐therm, Weatherite, York/JCI, others…
All produce chillers using HC and
- ther refrigerants (HFC HCFC
- ther refrigerants (HFC, HCFC,
ammonia, etc) Used for both refrigeration as well as air conditioning applications air conditioning applications
SLIDE 41 HC chillers
Benson Benson
―Air‐cooled (scroll, screw) ―Water‐cooled (scroll, screw)
Safety aspects Safety aspects
―Designed to AS/NZS 1677 ―Charge size up to 25 kg of R290 (per circuit)
Cost of R290 systems not more than HFC Cost of R290 systems not more than HFC R290 gives higher efficiency than HFC
SLIDE 42 HC chillers
Bundgaard Køleteknik
Air ooled and ater ooled hillers ―Air‐cooled and water‐cooled chillers
Safety aspects
―Designed to EN 378; up to 15 kg of R1270
Cost of R1270 systems marginally more than HFC products Capacity range: 10 – 600 kW
SLIDE 43 Ammonia chillers
― Air‐cooled and water‐cooled R717
Ammonia chillers
Bank 2,400 kW
(ammonia) chillers
― Designed to EN 378
Event hall 5,200 kW Railway station 1,250 kW
― Possible to install in public areas
- Cost more than HFC/HCFC
- R717 gives higher efficiency than
Institute 1,050 kW a ay stat o , 50
g g y HFC/HCFC
Shopping mall 1,020 kW Office complex, 4220 kW
SLIDE 44 Plug‐in chillers and freezers – efficiency
Examples of data for chiller & f b
R134a R744: R600a:
freezer cabinets
Source: Pedersen, 2008
R744: ‐11.7 % R600a: ‐27,7 %
Source: King et al, 2011 Source: van Gerwen et al, 2008
SLIDE 45
Small HC condensing units
Danfoss
R f R290 d i it
Small HC condensing units
―Range of R290 condensing units ―Smaller capacity range
Safety aspects
―Designed to EN 378/EN 6035‐2‐ 89
High efficiency
SLIDE 46
Ducted with HCs
Aicool, Indonesia
Ducted with HCs
―Rooftop ducted and ducted split systems developed to use R290
Safety aspects Safety aspects
―Designed to EN 378; up to 2.5 kg of R290 per refrigerant circuit C t li htl hi h th R22 t ―Cost slightly higher than R22 systems
SLIDE 47 Gram refrigeration
Plug‐in catering
Gram refrigeration
―Commercial stand‐alone cabinets; R290 is standard
Safety aspects
Designed to EN 60335 2 89 ―Designed to EN 60335‐2‐89 ―Charge size up to 150 g of R290 and R600a
Cost of R290 systems same as HFC products R290 has lo er energ cons mption than HFC options R290 has lower energy consumption than HFC options
SLIDE 48
Professional food and drinks preparation
Other appliances
drinks preparation equipment
―Shake sundae machine ―Post‐mix beverage machine ―Juice dispenser
Ice makers Cold storage
―Meat freezers and chilled produce rooms produce rooms
SLIDE 49
Viable application in larger coldstores Viable application in larger coldstores
NH3 HC s CO2 CO2
SLIDE 50
TESTED R22 & R290 SPLIT ACS AT HAT
R22 d l R22 model R290 model
SLIDE 51 Acceptable risk to Criteria Acceptable risk to public Risk from AC unit Frequency of ignition (per year) < 1×10‐5 5×10‐10 Ignition events per million per year 100 0.005 Number of units per ignition event 1 in 100,000 1 in 2,000 million Frequency of secondary fire (per year) < 1×10‐7 4×10‐12 Overpressure (kPa) < 15 4 Overpressure (kPa) < 15 4 Thermal intensity (s(kWm2)4/3) < 250 40 Frequency of fatality (per year) < 1×10‐6
SLIDE 52 Source: Eurammon, 2013
Comparison of certain options Comparison of certain options
COP
SLIDE 53 PRODUCT SAFETY ASSESSMENT
Regulations/ directives For flammable gas safety For pressure safety For electrical safety safety safety safety Atex LVD PED Harmonised standards EN 1127 1 EN 60335 2 24 EN 378 EN 1127‐1 EN 60079‐ EN 13463 EN 60335‐2‐24 EN60335‐2‐40 EN 60335‐2‐89 EN 378
SLIDE 54 G ll li bl I t ti l St d d R l ti d G id li Generally applicable International Standards, Regulations and Guidelines
ISO 5149/2014 Part 1-4 Refrigerating systems and heat pumps – Safety and environmental requirements EN 378/2012 Part 1-4 (Revi) Refrigerating systems and heat pumps safety and environmental requirements ( ) ISO 817 Refrigerants -designation and safety classification EN 13313:2010 Refrigerating systems and heat pumps competence of personnel EN 50110 2 100 O ti f l t i l I t ll ti EN 50110-2-100 Operation of electrical Installations DIN EN ISO 13585:2012 Brazing - Qualification test of brazers and brazing operators EN ISO/IEC 17024:2012 Conformity assessment - General requirements for bodies operating certification of persons 17024:2012 y q p g p ADR P200 European Agreement concerning the International Carriage of Dangerous Goods by Road DOT - 4B, 4BA, 4BW… Department of Transport (US) Welded steel cylinders made of definitely prescribed steels H h ld & i il l t i l li S f t P t 2 t 24 EN60335-2-24:2010 Household & similar electrical appliances – Safety Part 2 to 24: Refrigerating appliances, ice‐ cream appliances & ice makers EN60335-2-40:2003 Household & similar electrical appliances – Safety Part 2 to 40: Electrical heat pumps, air conditioners and dehumidifiers Household & similar electrical appliances – Safety Part 2 to 89: EN60335-2-89:2010 Household & similar electrical appliances – Safety Part 2 to 89: Commercial refrigerating appliances, incorporated/remote condensing unit or compressor
SLIDE 55 Specific Standards and Guidelines for flammable Refrigerants
EN6007:2009 Explosive atmospheres – Equipment - general requirements p p q p g q EN60079-10- 1:2009 Explosive atmospheres - Classification of areas – explosive gas atmospheres EN60079-14:2008 Explosive atmospheres – Electrical installations design, selection and erection EN60079-15:2010 Explosive atmospheres - Equipment protection by type of protection “n” EN 60079-15:2011-02 Equipment protection by type of protection "n“ (Gas detectors for leakage analysis) EN 60079-0 Explosive atmospheres - Part 0: Equipment - General requirements (Gas detectors) p p q p q ( )
Specific Guidelines for Natural Refrigerants
VDMA 24243-1/1:2006 Refrigerating machines and systems - Leak tightness of refrigerating systems and heat pumps - Leak detection/leak testing Part 1: Basic principles VDMA 24020-3 Operational Requirements for Refrigerating Systems – Part 3: Refrigerating Systems with Flammable Refrigerants VDMA 24020-1 Operational requirements for refrigerating systems Part 1: Ammonia refrigerating systems VDMA 24020-4 Operational requirements for refrigerating systems Part 4: CO2 refrigeration systems
SLIDE 56 PRODUCT SAFETY ASSESSMENT
A t f f diff t l k h l i d i t d
1.0E+0
Account for a range of different leak hole sizes and associated leak frequency
1.0E‐1 cy [/y] 1.0E‐3 1.0E‐2 eak frequenc 1.0E‐5 1.0E‐4 Le 0.0 1.0 2.0 3.0 4.0 Leak hole size [mm]
SLIDE 57 Comparative risk assessment – fridge vs. split RAC
- HC fridge/freezers excellent safety record
― Amongst approx. 700 million HC fridge/freezers, ignition frequency about 1×10‐8 per year… lower than “negligible”
vs.
― Comparison of risk enables understanding of significance of HCs in split AC Risk lower by factor of >100×
1.E‐06 1.E‐04 1/1,000,000 1/10,000
0.02 0.03 0.04 centration (kg/m3) mean (measurement) mean (model) 0 10 0.15 0.20 0.25 0.30 entration (kg/m3) mean model
1.E‐08 1/100,000,000 / , ,
0.00 0.01 100 200 300 400 Time (s) Floor conc 0.00 0.05 0.10 50 100 150 Time (s) Conce
150 g from refrigerator gives
1.E‐10 public fire fridge/freezer split RAC 1/10,000,000,000
refrigerator gives higher concentration than 400 g from AC
