A2L refrigerants risk assessment results
andrisk assessment plan for A3 refrigerant

July 12, 2017
JRAIA

Kenji Takaichi© 2013 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved.
ie_note1． Agenda【1】Introduction【2】A2L refrigerant risk assessment and the tolerable level【3】Study for A2L refrigerant air-conditioner(Residential air-conditioner andlight commercial air-conditioner)【4】Guideline of Japan refrigeration andair-conditioning industry association【5】Risk assessment plan for A3 refrigerant air-conditioner【6】Conclusion© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

12． Agenda【1】Introduction【2】A2L refrigerant risk assessment and the tolerable level【3】Study for A2L refrigerant air-conditioner(Residential air-conditioner andlight commercial air-conditioner)【4】Guideline of Japan refrigeration andair-conditioning industry association【5】Risk assessment plan for A3 refrigerant air-conditioner【6】Conclusion© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

2

3．

Organization of the research committee
Japan Society of Refrigeratingand Air Conditioning Engineers,
JSRAE
Chair: Hihara
Secretary: Fujimoto
University of TokyoJapan Automobile
Manufacturers Association, JAMA
Japan Societyof Refrigerating and Air Conditioning
Engineers, JSRAE
Japanese Refrigeration
and Air-conditioning Industry Association,
JRAIA
Research on the safetyof Mildly Flammable Refrigerants WG
Mini-Split Risk Assessment SWG(Ⅰ)(Ⅱ)
VRF Risk Assessment SWG© 2013 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved.

Chiller Risk Assessment SWG

Tokyo University of Science, Suwa
Kyushu University
National Instituteof Advanced Industrial
Science and Technology,
AIST
Observers
-NEDO
-METI
-KHK

3

4．

4

Schedule of Risk Assessment for AC and others

A2L refrigerant risk assessment has difficulty and long period
2011●Residential
AC

2012

2013

2014

2015

2017

2018

selling
Launched a new A2L air-conditioner.

●Commercial
AC

2016

New risk assessmentof A3 refrigerant.
selling

Launched a new A2L air-conditioner.

●buildmulti-AC●chiller●Others(Refrigerationequipment)© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

5． Agenda【1】Introduction【2】A2L refrigerant risk assessment and the tolerable level【3】Study for A2L refrigerant air-conditioner(Residential air-conditioner andlight commercial air-conditioner)【4】Guideline of Japan refrigeration andair-conditioning industry association【5】Risk assessment plan for A3 refrigerant air-conditioner【6】Conclusion© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

56． Features of different Air-conditioners

6

Product

Residential AC

Commercial package AC

VRF

Cooling Capacity

2.2-8 kW

3.6-30 kW

14-168kW

Refrigerant Charge

1-4kg

2-19 kg

5-100 kg

Installation
Outdoor : Indoor

1:1(-5)(Indoor: multi rooms)

Type of indoor unit

Wall mounted
Floor mounted
Ceiling cassette

1:1(-4)(Indoor: single room)
Wall mounted
Ceiling cassette
DuctedFloor mounted

1-3：1-64(Indoor : multi rooms)
Wall mounted
Ceiling cassette
DuctedFloor mounted

Air-coolingAir-cooling
Ice-storage

Air-cooling
Ice-storage
Water-coolingresidence

OfficeKitchen/Dining room
Factory
Karaoke room (Tightness)

OfficeKitchen/Dining room
Factory
Karaoke room (Tightness)

GroundBalcony

GroundEach floor
Semi-underground
Narrow space

GroundEach floor
Semi-underground
Machinery room

Storage

Bulk storage warehouse
Narrow warehouse

Bulk storage warehouse
Narrow warehouse

Bulk storage warehouse

Logistics

Truck
Mini-van

Truck
Mini-vanType of outdoor unit

Indoor install location

Outdoor install location

Truck© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

7． Hazards of R32 and R1234yf ; A2L

Hazards of R32＆ R1234yf

Pressure（50℃）

Toxicity

R410A

3.07MPaR410A None

R32,ｙｆ

3.14MPa

R32,ｙｆ None

Flammability
ChangePoint

R410A No
R32,ｙｆ Mildly

Ignition Source
R410A

None

R32,ｙｆ

Open flame

Diesel explosion
R410A

Yes

R32,ｙｆYes

yf:R1234yf

・Flammability and ignition source are studied in changing to R32 and R1234yf
・Diesel explosion and contact flame study for R32 and R1234yf are performed universities and
AIST don’t change the study result with R410A© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

78．Procedure of risk evaluation in ISO/IEC guide51

JRAIA has been conducting the risk assessmentin accordance with ISO/IEC guide 51.
START
１

Identify user, intended use, reasonably foreseen misuse.
２

５
Risk Reduction

３
４

Hazard Identification
Estimation of risk
Evaluation of risk
Tolerable？

Validation and documentation
8 All Rights Reserved.
© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association.

89． Start ：Identify the tolerable risk

START

Guide 51 ;
 Safety means ;Freedom from risk which is not tolerable.

１
Identify user etc.
２ Hazard
Identification

 Tolerable risk ;Accepted in a given context based on the current
values of society.

５
Risk
Reduction

３

Estimationof risk

４ Evaluationof risk

Toler
able
？

Validation anddocumentation

Examples of the current values in Japan
1. Chemical factory
2. Car
3. Home appliance: 10-5 [accidents/(year*site)]: 10-7 [accidents/(year*unit)]: 10-8 [accidents/(year*unit)]
for one million units in the market

JRAIA decided the accident less than once
per century would be tolerable for use.
© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

910． Start ：Identify the tolerable risk

Tolerable value is dependent on the numberof units in the market for each products
START
１
Identify user etc.
２ Hazard
Identification
５
Risk
Reduction

３

Estimationof risk

４ Evaluationof risk

Toler
able
？

Validation anddocumentation

The tolerable value was increased by 10 times because
they are handled by trained professionals except when use.

Product/
SystemNo. ofunits inmarketTolerable value
Use

Install,service
etc.

Residential A/C

1*108

1.0 * 10-10

1.0*10-9

Commercial A/C

7.8* 106

1.3 * 10-9

1.3 * 10-8

VRF

1*107

1.0 * 10-9

1.0 * 10-8

Chiller

1.34*105 7.5 * 10-7

7.5 * 10-7

GHP

4.5*105

3.7 * 10-9

3.7 * 10-8

Display cabinet

4.9*105

2.0 * 10-8

2.0 * 10-7

Condensing unit

1.46*105 6.9 * 10-8

6.9 * 10-7

The tolerable value was increased in chillers© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

1011． Agenda【1】Introduction【2】A2L refrigerant risk assessment and the tolerable level【3】Study for A2L refrigerant air-conditioner(Residential air-conditioner andlight commercial air-conditioner)【4】Guideline of Japan refrigeration andair-conditioner industry association【5】Risk assessment plan for A3 refrigerant air-conditioner【6】Conclusion© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

11

12．

Probability of presence of ignition source ; A2L

Comparison of the probability of the presence of ignition sources for air-conditioners
Ignition source [Units]
Indoor Unit
Air Cleaner
Humidifier
MobilePC
Light
Tracking
Refrigerator
Freezer
Dishwashers
Phone
TV
Exhaust Fan

Appliances

Spark[times/m3min]

Smoking Equipment(Match/Oil lighter)
Ignition Equipment(Match/Oil lighter)
Water Heater
Heater
Kitchen Burner
Gas Rice Cooker
Combustion
equipment
Gas Oven
Coffee Siphon
Gas Burner
Gas Roaster

Open flame[-]

Ignition Source [Units][times/m3min]

Smoking
Equipment(Match/Oillighter)

WorkerUser

WorkerOpen
flame

Kitchen

5.7×10-16

4.5×10-16

7.0×10-16

1.6×10-15
1.1×10-15
1.6×10-14
3.8×10-15
9.7×10-15
2.5×10-16
1.1×10-15
5.5×10-15

5.6×10-16
7.6×10-16
1.2×10-14
1.3×10-15
6.7×10-16-

Smoking
User

P=installed units×accident rate/numbers on market/space volume/(365×24×60)
Fire accident rate: 3 times/year (NITE), numbers on market: 88.4 mil. units
Installed: 0.2 units/room, accident rate: 3.6/year, numbers on site: 17.3 mil
Installed: 0.09 units, accident rate: 3/year, numbers on site: 8.11 mil
Installed: 8.12, accident rate: 23/17 years (LT10year), numbers: 23.9 mil.
Installed: 8.12, accident rate: 174/17 years (LT10year), numbers on site: 11.8 mil
Installed: 10/15, accident rate: 227/17 years (LT10year), numbers on site: 165 mil
Installed: 10/15, accident rate: 202/17 years (LT10year), numbers on site: 298 mil
Installed: 0/3, accident rate: 267/17 years (LT10year), numbers on site: 3.88 mil
Installed: 0/2, accident rate: 16/17 years (LT10year), numbers on site: 0.658 mil
Installed: 0/2, accident rate: 71/17 years (LT10year), numbers on site: 1.511 mil
Installed: 0/1, accident rate: 18/17 years (LT10year), numbers on site: 5.67 mil
Installed: 0/1, accident rate: 355/17 years (LT10year), numbers on site: 25.2 mil
Installed: 0/4, accident rate: 105/17 years (LT10year), numbers on site: 5.96 mil
P=smoker presence rate in the room×0.209×17.1/space volume/(24×60) ×0.05
Smoker presence in the room: 0.1, smoking rate: 0.209 (Japanese Adult)
Smoking numbers: 17.1/day/person(2013JT), use rate Match/Oil lighter: 0.05
P=5/space volume/(24×60)×0.05
Using rate for gas burner 5 times/day, Use rate Match/Oil lighter: 0.05
[Office]inst.: 0.1, Use rate: 2 h/day, [Kitchen]2, 60 min/day. Installed rate: 0.8
Installed: 0.001 units, Use rate: 4 h/day, 60 day/year
Installed: 15 units, Use rate: 0.023. Installed rate: 0.9
Installed: 2 units, Use rate: 2 h/day. Installed rate: 0.3
Installed: 2 units, Installed rate: 2.9×10-4
Installed: 3 units, Installed rate: 2.9×10-4
Installed: 0.5 units, Use rate: 0.2 min/time。10 times/day
Installed: 2 units, Installed rate: 2.9×10-4●Sparks
・Appliance (cause of fire), match, oil lighter andmetal spark by forklift are ignition sources.
・Static electricity by human body, electric gas lighterand electric parts in unit (less than 5 kVA) aren’t
Individual
Semi
Narrow
Groundignition sources.
floor-UndergroundSpace
8.8×10-7--

1.2×10-6

8.3×10-3-

6.7×10-2
2.7×10-5
3.1×10-1
5.0×10-2
5.8×10-4
8.7×10-4
6.9×10-4
5.8×10-4

1.4×10-14

Outdoor Unit
Spark

Office9.5×10-14

2.5×10-14

9.1×10-14

3.6×10
1.3×10
1.7×10
1.7×10●Open
flame
・Open flame brought into the space where leaked
5.6×10
5.4×101.1×101.1×10refrigerant exists are regarded as ignition sources.
lighter, candle,
gas1.5×10
burner for blazing and etc.
6.0×10 Oil 3.0×10
1.5×10・Combustion equipment like fan heater aren’t
9.3×10ignition
1.3×10sources.
9.3×10
9.3×10
-10

-9

-9

-9

-8

-8

-7

-7

-8

-8

-7

-7

-6

-6

-6

-6

6.6×10-4

2.2×10-4

2.2×10-4

2.2×10-4[-]
BoilerP = 5.6/7,800,000/space volume/(365×24×60)
Fire accident rate: 5.6 times/year, numbers: 7.8 mil. units[Worker]
P = Smoking rate(near unit)×service rate ｘ 0.322 ×
Rule disregarding rate during work: 0.01
[User]
P = User presence rate (near units) × 0.209 × 17.1/space v(Japanese Adult), Smoking area rate: EF: 0.5, others: 0.9[Worker]
P = Worker presence rate (near units) × service rate ｘ0.322(smoking rate) × 16 (cigarettes) × 5/space volume(seconds/1 cigarette: open fire consistence)/(24 × 60 ×60) × 0.01 (manual ignorance rate)[User]
P = User presence rate (near units) × 0.209 (smoking rate)
P=Use rate × Installed rate
Installed rate: 0.1%

© 2013 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved.

13． Risk assessment ; A2L●examination of ignition source●From study of R32⇒Mildly flammable refrigerant in a room air-conditioner leaked in the space,but no flame propagation across the whole space⇒Ignition was observed at the outlet of piezo lighter,but no flame propagation of lighter to n-butane/mildly flammable refrigerant mixture⇒Under 3mm of clearances in case cover,mildly flammable refrigerant no flame propagation through clearances

R410;A1

R32;A2L（Blazing torch,
Oil lighter, Candle）

No ignition

Rare ignition●Electric spark

No ignition

Rare ignition●Static electricity

No ignition

No ignition

Ignition source●Open flame© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

1314． Human error●Probability of human error in Install and service stages and etc. of ACs

1/10
1/100 to 1/10000
1/100000
1/10●JRAIA adopts 1/1000
Reference : Hashimoto, K., “Human safety engineering”,
Central Association of Work Accident Protection, (1984), pp85-97 (in Japanese)© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

1415． FTA for all knowledge and experimental results●Ignition energy& flame quenching●Flammable gas region●Ignition of fossil-fuel appliance

FTA●Human error© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

1516． FTA of life cycle stage
Ignition室内での着火
at disposal

Disposal
室内での着火Ignitionat serving

repairing

Ignition at
HFC32 2.0E-14～3.7E-10
Dii
HC290 5.9E-09～1.1E-04
HFC32 4.6E-17～8.6E-13
HC290 1.3E-12～2.4E-08
室内での着火Ignitionin outdoor

Outdoor

Ignition at
Dii
可燃範囲内にHFC32 4.6E-17～8.6E-13
着火源が存在する
HC290 1.3E-12～2.4E-08
Ignition at
室内での着火Ignitionin indoor
Dii
HFC32 4.6E-17～8.6E-13HFC32 2.0E-14～3.7E-10
可燃範囲内に HC290 1.3E-12～2.4E-08
室内機からのHC290 5.9E-09～1.1E-04
着火源が存在する
可燃冷媒漏洩

機器据付け時

据付け時の着火

Install（未対策ケース）

Dii

R290
R32

2.9E-09～4.3E-08
HFC324.6E-17～8.6E-13
HFC32
8.0E-05～1.2E-03
HC2901.3E-12～2.4E-08
HC290
冷媒への着火8.0E-028.0E-02

HFC32 2.0E-14～3.7E-10
HC290 5.9E-09～1.1E-04

可燃範囲内に HFC32 2.0E-14～3.7E-10
室内機からの着火源が存在する HC290 5.9E-09～1.1E-04
可燃冷媒漏洩

運転中

HFC32 1.6E-07～2.0E-04
HC290 1.6E-07～2.0E-04

HFC32 0.1
HC290 0.1Indor

HFC32 1.4E-07～2.1E-06
HC290 4.1E-02～6.2E-01

HFC32 0.9
HC290 0.9

HFC32 2.0E-14～3.7E-10
室内機からの
5.9E-09～1.1E-04
HC290
停止中
可燃冷媒漏洩
急速冷媒漏洩
HFC32 1.6E-07～2.0E-04
HFC32 0.9
HFC32 1.4E-07～2.1E-06
室内機からの発生頻度／ｙHC290 冷媒漏洩発生確率
HC290 4.1E-02～6.2E-01
HC290 1.6E-07～2.0E-04
0.9

可燃範囲内に着火源が存在する

運転中

HFC32 1.6E-07～2.0E-04
HFC32 0.1
急速冷媒漏洩
HC290 1.6E-07～2.0E-04 室内機からのHC290 0.1
発生頻度／ｙ
冷媒漏洩発生確率

停止中

HFC32 1.6E-07～2.0E-04
HC290 1.6E-07～2.0E-04

急速冷媒漏洩
HFC32 1.6E-07～2.0E-04
HFC32 0.1
室内機からの
P１/２
２０１１．１２．７
発生頻度／ｙHC290 1.6E-07～2.0E-04
HC290
0.1
冷媒漏洩発生確率
可燃範囲内に室内機からのHFC32 4.0E-07～5.0E-04
HFC32 0.4
運転中
Indor
着火源が存在する
可燃冷媒漏洩
HC290 4.0E-07～5.0E-04
HC290 0.4

HFC32 2.9E-09～4.3E-08
HC290 8.0E-05～1.2E-03
Ignition at install 室内機からの可燃範囲内にIgnition at
R290
3.8.E-05～
3.9.E-05
着火源が存在する
可燃冷媒漏洩
R32
6.1.E-07～
1.3.E-06

微燃性冷媒安全検討WG（ミニスプリットリスクアセスメントSWG）

Indor

Indor

HFC32 2.0E-14～3.7E-10
HC290 5.9E-09～1.1E-04
室内機からの可燃冷媒漏洩

HFC32 2.9E-09～4.3E-08
HC290 8.0E-05～1.2E-03

Indoor

エアコン据付頻度
2.1

HFC32 2.0E-14～3.7E-10
HC290 5.9E-09～1.1E-04

停止中 HFC32 4.0E-07～5.0E-04
HC290 4.0E-07～5.0E-04
1.4E-07～2.1E-06
1.6E-07～2.0E-04
HFC32 HFC32
HFC32
HFC32 0.9
2.0E-14～3.7E-10
急速冷媒漏洩
4.1E-02～6.2E-01
HC290 HC290
HC290 1.6E-07～2.0E-04 室内機からのHC290 0.9
5.9E-09～1.1E-04
発生頻度／ｙ
冷媒漏洩発生確率

パナソニック（株）

HFC32 0.4
HC290 0.4

HFC32 4.0E-07～5.0E-04
HFC32 時間・体積当たりのHFC32 可燃になる
HFC32 0.4
0.4
4.0E-07～5.0E-04
可燃になる
時間・体積当たりのHC290 4.0E-07～5.0E-04
HC290 0.4
HC290
HC290 0.4
4.0E-07～5.0E-04
空間体積と持続時間
着火源の存在確率
空間体積と持続時間
着火源の存在確率
急速冷媒漏洩
室内機からの min･m3
室内機からのmin/m3
min･m3
min/m3
可燃範囲内に可燃範囲内に室内機からの発生頻度／ｙ
冷媒漏洩発生確率
運転中 冷媒漏洩発生確率
停止中
着火源が存在する
可燃冷媒漏洩
着火源が存在する
可燃冷媒漏洩
HFC32 4.0E-07～5.0E-04
HFC32 0.4
HFC32 4.0E-07～5.0E-04
HFC32 0.4
R290 4.8E-04～ 4.8E-04
R290 2.0E-06～ 1.0E-05
HC290 4.0E-07～5.0E-04
HC290 4.0E-07～5.0E-04
0.1
1.4E-07～2.1E-06
1.6E-07～2.0E-04
HFC32 2.9E-09～4.3E-08
HFC32 1.6E-07～2.0E-04
HFC32
HFC32HFC32
HFC32
HFC32 0.9時間・体積当たりのR32
5.6E-06～ 5.6E-06～ 1.0E-05
5.0E-040.4R32 2.0E-06
5.7E-06～8.6E-05
HFC32 HC290
HFC32 2.4E-02 HC290 0.4 HFC32 5.7E-06～8.6E-05
可燃になる
時間・体積当たりの可燃になる
0.1
4.1E-02～6.2E-01
HC290 8.0E-05～1.2E-03 空間体積と持続時間
HC290 1.6E-07～2.0E-04
HC290
HC290HC290
HC290 1.6E-07～2.0E-04
HC290 0.9 HC290
5.7E-06～8.6E-05 空間体積と持続時間
7.2E+03
HC290 1.4E+01
HC290 5.7E-06～8.6E-05
着火源の存在確率
着火源の存在確率
min･m3
min/m3
min･m3
min/m3R290
R32

4.8.E-04
7.6.E-06～～

4.9.E-04
1.6.E-05

急速冷媒漏洩
室内機からの発生頻度／ｙ

作業者の喫煙以外による着火

作業者の喫煙による着火接続配管（壁面内）

着火源が
存在する

室外機

室内機

R290
R32

4.8E-04
5.6E-06

R290
R32

冷媒漏洩
発生確率

着火源が
存在する

R290
R32

1.3E-07
4.3E-13～～～ 6.2E-09
可燃になる～ 2.1E-14
空間体積と持続時間
急速冷媒漏洩
min･m3
発生頻度／ｙ4.1E-10
1.4E-15

冷媒漏洩発生確率（工事不良による漏洩）
2.4

5.8E-09
6.7E-10

R290
R32

可燃になる
空間体積と持続時間
min･m3R290
R32

7.2E+02
2.4E-03

HFC32 5.0E-04
HC290 1.4E+01

8.5E+03
1.0E+02

R290
R290

可燃範囲内
に着火源が存在する確率

1.0E-02
1.0E-02

R290
R290

可燃になる

1.9E-06
6.5E-12R290
R32

1.0E+00
1.0E+00

4.4E-07
5.1E-08～～

6.7E-06
7.7E-07

R290
R32

HFC32 4.0E-07～5.0E-04

HFC32 0.4

4.0E-07～5.0E-04
HC290
2.4E-02
HFC32
R290 1.7E-03～ 8.4E-03
1.7E-03～ 8.4E-03
HC290 R327.2E+03

HC290 0.4
HFC32 5.7E-06～8.6E-05
HC290 5.7E-06～8.6E-05

可燃冷媒が漏洩

1.3E-02
1.3E-02

HC290 5.7E-06～8.6E-05

3.2E-03
3.2E-03

時間・体積当たりの空間体積と持続時間
着火源の存在確率
急速冷媒漏洩
HFC32 室内機からの2.4E-02
min･m3
min/m3HFC32 5.7E-06～8.6E-05
発生頻度／ｙHC290冷媒漏洩発生確率
HC290 5.7E-06～8.6E-05
7.2E+03

冷媒漏洩
発生確率

バルブ誤動作
による漏洩
2.7

時間・体積
あたりの存在確
率
2.11

R290
R32

1.8E-10
1.8E-10～～

時間・体積当たりの着火源の存在確率
min/m3

2.7E-09
2.7E-09

可燃空間の
時間・体積
2.5

R290
R32

据付者が
指示を無視
2.17

喫煙しながら据付ける確率2.16

4.0E-06
4.0E-06
可燃空間の
時間・体積
2.2

可燃空間の
時間・体積
2.10

8.8E-08
1.0E-08

着火源が存在する

HC290 1.4E+01
1.2E+02
1.4E+00～～

HFC32 4.0E-07～5.0E-04
HFC32 0.4
HC290 4.0E-07～5.0E-04
HC290 0.4
HFC32 5.0E-04
HFC32 5.7E-06～8.6E-05
R290
R32

R290
R32

据付者の喫煙率2.15

時間・体積当たりの着火源の存在確率
HFC32 5.7E-06～8.6E-05
HFC32 5.0E-04
室内機からのmin/m3
6.0E-01
R290 2.0E-01
HC290 1.4E+01
5.7E-06～8.6E-05
冷媒漏洩発生確率R290
R32HC290
6.0E-01
R290 2.0E-01

R290
R32

時間・体積
あたりの存在確
率
2.11

工事不良
（接続ミス・忘れ）
による漏洩
2.12

R290
R32

R290
R32

1.4E-02
1.4E-02

4.0E-04
4.0E-04

HFC32 5.7E-06～8.6E-05
HC290 5.7E-06～8.6E-05
R290
R32

接続配管が
壁面内に存在
する確率
2.13

R290
R32

1.0E-01
1.0E-01

7.8E-02
9.0E-03

接続配管が着火源と同一
壁面に存在
2.14

R290
R32

R290
R32

工事不良
（接続ミス・忘れ）
による漏洩
2.8

4.4E-03
4.4E-03

R290
R32

5.7E-06
5.7E-06～～

8.6E-05
8.6E-05

冷媒漏洩
発生確率

R290
R32

可燃になる
空間体積と持続時間
min･m3R290
R32

4.4E-03
4.4E-03

バルブ誤動作
による漏洩
2.7

時間・体積
あたりの存在確率
2.11

R290
R32

4.3E-03
4.3E-03

冷媒充填時の接続不良による
漏洩
2.9

HFC32 2.4E-02
HC290 7.2E+03
R290
R32

4.4E-03
4.4E-03

1.7E-02
1.7E-02

サービスマン側へ冷媒が漏洩する
確率

時間・体積当たりの着火源の存在確率
min/m3
R290
R32

工事不良
（接続ミス・忘れ）
による漏洩
2.8

R290
R32

7.9E-03
7.9E-03

1.0E-01
1.0E-01～～

5.0E-01
5.0E-01

冷媒充填時の接続不良による
漏洩
2.9

HFC32 5.7E-06～8.6E-05
HC290 5.7E-06～8.6E-05
R290
R32

4.4E-03
4.4E-03

FTA from Install to Disposal

1.0E-01
1.0E-01© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

1617． Results of risk assessment ; A2L

Wall mount type air conditioner
Risk: Ignition Probability
R32

R1234yf

Logistic

4.1×10-17

4.5×10-17

Installation

2.7×10-10

3.1×10-10

Use (Indoor)

3.9×10-15

4.3×10-15(Outdoor)

1.5×10-10

2.1×10-10Service

3.2×10-10

3.6×10-10

Disposal

3.6×10-11

5.3×10-11

・Probability of indoor use is lower than tolerable level 10-10.
・tolerable level 10-9 in service, installation and others is satisfied in all stages.
・The ignition probability of R32 and R1234yf is nearly same.
（Attention : R1234yf is extended flammable range in high humidity condition.
© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

1718． Agenda【1】Introduction【2】A2L refrigerant risk assessment and the tolerable level【3】Study for A2L refrigerant air-conditioner(Residential air-conditioner andlight commercial air-conditioner)【4】Guideline of Japan refrigeration andair-conditioner industry association【5】Risk assessment plan for A3 refrigerant air-conditioner【6】Conclusion© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

18

Procedure of risk evaluationin ISO/IEC guide51
JRAIA has been conducting the risk reduction
by measures and regulations
START
１

Identify user, intended use, reasonably foreseen misuse.
２

５
Risk Reduction

３
４Commercial A.C. and so on needsafety measures.
JRAIA made these measures toguidelines and requirements.

Hazard Identification
Estimation of risk
Evaluation of risk
Tolerable？

Validation and documentation
19 All Rights Reserved.
© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association.

1920． The result of commercial air-conditioner risk assessment ; A2L
The dominant risk factors and safety measures for step
Dominant risk factors

FactorFloormounted
indoor units

Item
Safetymeasures

Semiunderground(Depth≧1.2
m)Leakage gas

Item

Air circulation/
Ventilation

Safetymeasures

FactorOutdoors
Narrow
space

Item
Safetymeasures

Installation/
Service stages

Disposal stage

Leakage gas
Leakage gas
Human error
Air circulation/
Gas burnerHigh concentration
Ventilation(brazing)“Unit’s fan operating with a leak detector” “Education for workers” and(Min air flow: 10m3/min and minimum “Carrying a portable leak detector”
speed: 1.0m/s)

FactorOutdoors

Usage stage

Presence of ignition
sources

Human error

Human error

BoilerRefrigerant recovery
Gas burner (brazing)

Refrigerant recovery
Wiring for power
supplyIf refrigerant amount>1/2xLFLx1.2,“Unit’s fan operating with a leak detector(Air flow rate≧4.0[m/s], Depth≦2mand distance from discharge grille ≦3m)”,or “Mechanical ventilation”
Presence of ignition
Leakage gas
sources
Air circulation/
Opening

Boiler“Opening of 0.6 m or more for one side”“Education for workers” and“Carrying a portable leak detector”

Human error

Human error

Refrigerant recovery
Wiring for power
supply“Education for workers” and“Carrying a portable leak detector”
Refrigerant recovery
Gas burner (brazing)

Commercial A.C. needs safety measures.
JRAIA made these measures to Guidelines and requirements.
© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

2021． Guideline and Requirements
No. Std. GL.

of JRAIA

Title

Application

1

JRA GL-20 Appropriate measures to prevent combustion against
refrigerant gas leakage from the refrigerant charged
equipment using particular inert gas

General2

JRA 4068

Leak detector and
alarm

3

JRA GL-15 Guideline of design construction for ensuring safety
against refrigerant leakage from chiller using lower
flammability(A2L) refrigerants”

Chiller
7.5kW～

4

JRA 4070

Commercial A.C.
3～20ｔ

5

JRA GL-16 Guideline of design construction for ensuring safety
against refrigerant leakage from commercial air
conditioners using lower flammability(A2L)
refrigerants

Requirements of refrigerant leak detector and alarmfor air conditioning and refrigeration equipment

Requirements for ensuring safety against refrigerantleakage from commercial air conditioners using lower
flammability(A2L) refrigerant© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

2122． Guideline and Requirementsof JRAIA

No. Std. GL.

Title

Application

6

JRA 4072

Requirements for ensuring safety against refrigerantleakage from commercial refrigeration equipmentusing lower flammability(A2L) refrigerantscommercial
refrigerationequipment

7

JRA GL-18

Guideline of design construction for ensuring safety
against refrigerant leakage from commercial
refrigeration equipment using lower
flammability(A2L) refrigerants

8

JRA 4073

Requirements for ensuring safety against refrigerantleakage from commercial packaged air conditioner
for facilities using lower flammability(A2L)
refrigerants

9

JRA GL-19

Guideline of design construction for ensuringsafety against refrigerant leakage fromcommercial packaged air conditioner for
facilities using lower flammability(A2L)
refrigerantscommercial
packaged A.C
for facilities© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

2223． Agenda【1】Introduction【2】A2L refrigerant risk assessment and the tolerable level【3】Study for A2L refrigerant air-conditioner(Residential air-conditioner andlight commercial air-conditioner)【4】Guideline of Japan refrigeration andair-conditioner industry association【5】Risk assessment plan for A3 refrigerant air-conditioner【6】Conclusion© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

2324． Direction and Schedule ; A3 refrigerant■ Direction
・In the trend of deregulation of A3 refrigerants, JRAIA will propose air-conditioner be secured.
・Based on RAC's risk assessment method and results for A2L refrigerant , JRAIA also
conducts risk assessment for A3 refrigerant and recommended measures to ensure safety
from the evaluated result.
・JRAIA collaborates with universities and research institutions to compare the hazards to
the refrigerant of A2L and A3 refrigerants.

■ Schedule・First year ; A3 refrigerant risk assessment and countermeasure
・Second half year ; Estimation method and make plan for estimation
・ Last year ; Practical estimation for risk assessment.

2016

2017

2018

6,7/12/2018
Kobe Symposium

Risk assessment
Risk assessment

Risk reduction Reduction effectiveness

Hazard estimation
Plan for estimation

Hazard estimation© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

2425． Probability of presence of ignition source ; A3

Ignition Source [Units]

Ground

Each
Floor

Semi
-Undergr
ound

NarrowSpace

Outdoor Unit

1.4×10-14

9.5×10-14

2.5×10-14

9.1×10-14

Worker

3.6×10-10

1.3×10-9

1.7×10-9

1.7×10-9

User

5.6×10-8

5.4×10-8

1.1×10-7

1.1×10-7

6.6×10-4

2.2×10-4

2.2×10-4

2.2×10-4

Spark[times/m3min]

Smoking
Equipment(Match/Oillighter)

WorkerOpen
flame

Smoking
User●Open flame
・All open flame are ignition sources
Oil lighter, candle etc.
-8-8
6.0×10
3.0×10
1.5×10-7 brought
1.5×10-7
・Open
flame
into the space whereleaked refrigerant exists are regarded as-6ignition
9.3×10
1.3×10-6sources.
9.3×10-6
9.3×10-6[-]
Boiler

P=5.6/7,800,000/space volume/(365×24×60)
Fire accident rate: 5.6times/year, numbers:7.8mil. units[Worker]
P=Smoking space rate×service rateｘ0.322×16/spacevolume/(24×60) ×0.05[spark]×0.01
Smoking rate near unit：G： 0.2, EF：0.1, SU/NS： 0.5
Service rate: 0.1
Smoking rate for workers： 0.322(Japanese Male：JT)
Smoking numbers for workers：16/day (Japan)
Use rate for match/oil lighter: 0.05
Rule disregarding rate during work: 0.01
[User]
P=Smoking rate near units×0.209×17.1/spacevolume/(24×60)×0.05[spark]×smoking area rate
Smoking rate near units: G/SU/NS: 0.05, EF: 0.0125
Smoking rate： 0.209, Numbers： 17.1/day (Japanese
Adult), Smoking area rate: EF: 0.5, others: 0.9[Worker]
P=Smoking space rate×service rateｘ0.322×16×5/spacevolume/(24×60×60) ×0.01[User]
P=Smoking rate near units×0.209×17.1×5/space volume/(24×60×60)×smoking area rate
Open flame generating time: 5s
P=Use rate×Installed rate
Installed rate: 0.1%
Use rate…Ground： 0.66(24h/day, 20days/month）
Others： 0.22（8h/day, 20days/month）© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

2526． Ignition source ; A3

●Ignition source for A3 refrigerant
R410;A1

R32;A2L

Ignition source

R290;A3（Propane）●Open flame（Blazing torch,
Oil lighter, Candle）

No ignition

Rare ignition

Ignition●Electric spark

No ignition

Rare ignition

Ignition●Static electricity

No ignition

No ignition

Occasional
Ignition© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

2627． Leak simulation ; A3 refrigerant
Generation of Flammable cloud near the floor (Red area)●CFD results●Condition : refrigerant amount 500g, leakage speed125g/min
Time
Cross section

Red areas areflammable
cloud

Concentration

HeightTime© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

2728． Ignition and extinction property ; A3
１．Ignition property

２．Quenching distance and mass
burning rate
The substance at the lower left of the graphhas characteristics thatit easily ignites and burns violently.

Flame generation speed

R32

The substance at the lower rightis dangerous.

Quenching distanceand mass burning rate
Minimum ignition energy© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

2829． Real leakage ignition study ; A3
●Balcony is few ignition sources but A3 flammable refrigerant leaks
make serious accidents
Collective apartment

Real balcony© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

2930． Real leakage ignition study ; A3
●Balcony is few ignition sources but A3 flammable refrigerant leaks
make serious accidents
L:3.6mSerious flame

Real model balcony
By Infrared camera
High temp flame is white

W:1.0m
H:2.8mHh:1.3m(Handrail)

Red areas areflammable
religion

Leakage inlet© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

30

31． RA Step for A3 refrigerant
Establishment for safety specification of A3 refrigerant●Flammable Volume and time Integration
Step

Terms

① Evaluated product・Setting of evaluated product and usage condition
・Making the risk scenario
・Manufacturing, Transportation, Install, Use, serves, recycle②Risk assessment◎ Basic items of risk estimation
・ Installation case (leaky space model setting)・ Refrigerant leak rate and leak speed
・ Ignition source existence probability ←Identification the ignition source
・ Flammable cloud ← CFD, simplified calculation③ Measures④In market(Regulation）

・Equipment measures: Air circulation and ventilation fan, shutoff valve, alarm・ Document correspondence: Instruction manual, warning display
・ Regulatory compliance: regulations, industrial association manual・Regulatory compliance: regulations, industrial association manual・Document correspondence: Instruction manual, warning label
・Maintenance of work procedures manual・Improvement of working accuracy in education and training© 2016 JRAIA The Japan Refrigeration
Air TheConditioning
Industry Association.
All Rights Reserved.
© 2017 and
JRAIAJapan Refrigeration
and Air Conditioning
Industry Association. All Rights Reserved.

3132． Agenda【1】Introduction【2】A2L refrigerant risk assessment and the tolerable level【3】Study for A2L refrigerant air-conditioner(Residential air-conditioner andlight commercial air-conditioner)【4】Guideline of Japan refrigeration andair-conditioner industry association【5】Risk assessment plan for A3 refrigerant air-conditioner【6】Conclusion© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

3233． Conclusion
RA ; Risk assessment

1．Risk assessment for A2L refrigerant
・Completion of RA for residential air-conditioner⇒The cumulative sales units (from 2012 to 2016) is 25 million in Japan・Completion of RA for commercial air-conditioner⇒The cumulative sales units (from 2012 to 2016) is 3.5 million in Japan・Promotion on RA for other refrigeration products
Display cabinet, GHP, Condensing unite and etc.
2．Establishment of Japanese type risk assessment
3．Guideline and requirements of JRAIA for A2L・Apply the guideline and requirements for products in Japan・Reflecting on international safety standards
4．Risk assessment for A3 refrigerant
・Promotion of appropriate FTAs based on research withindustry-university collaboration.
・ Review of FTA results and planning of measures,
then demonstration of its effect (At Kobe symposium in 2018)© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

33

Thank you very much

© 2017 JRAIA The Japan Refrigeration and Air Conditioning Industry Association. All Rights Reserved.

34