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Dr Daniel Colbourned.colbourne@re-phridge.co.uk
36th Meeting of the Open-ended Working Group of the Parties to the Montreal Protocol – Side Event
UNEP OZONACTION: SAFE USE OF ALTERNATIVES TO HCFCs
A brief overview of safety issues to beconsidered when alternative
refrigerants are adopted
Types of refrigerants
CFC HCFC PFC HFE AmmoniaCarbon dioxideHydrocarbonEthers
un-saturated
HFC
saturated HFC
un-saturated
HC
saturated HC
Fluorinated Non-fluorinated
R11R12R13
R113R114R115
R22R123R124
R142b
R318R218
R1234yfR1234zeR1243zf
R161R32
R125R134aR143aR152a
RE245cb R717R744R1270R1150
R170R290R600
R600aR601
R601a
Refrigerants
RE170
“natural” synthetic
HFC
un-saturated
HCFC
saturated HCFC
R1233zdR1233xf
Selection of suitable alternatives
Hazards of all refrigerants
Release of refrigerant
Pressure rise
Presence of dangerous
concentration
Chronic physical impact
Acute physiological
impact
Physical damage to structure
Injury to persons
Rapid boiling of liquid
Ignition of flammable
mixture
Freeze burn
Asphyxiation
Secondary fireThermal radiation
Rapid de-compression
The new importance of safety…
HCFC-22
HCFC-123
R-717
R-744
HFC-32
HC-290
HC-1270
L-40
R-444A
R-444BHFC-1234yf
DR-7
DR-5R-446A R-447A
Higher toxicity
Higher pressure
R-410A
Flammable
Refrigerant safety classification
Lower (chronic) toxicity
Higher (chronic) toxicity
A1 B1
A2 B2
A3 B3
No flame propagation
Flammable
Higher flammability M
ore
oner
ous
requ
irem
ents
More onerous requirements
A2L B2LLower flammability
Number for state State Letter(s) for hazard Hazard Examples
2Liquefied gas (under
pressure)
A Non-flammable HCFC-22, R-744F Flammable HC-290, HFC-32
TC Toxic and corrosive R-717
UN system
Refrigeration industry system (Ashrea, ISO)
Accounting for the lifetime of equipmentPR
ODUC
TION
END-
OF-LI
FEOP
ERAT
ION
design
manufacture
storage and distribution
installation
in-use
decommissioning
product development
commissioning
service
disposal
technical managersdevelopment engineers
design engineers
production managerassembly line technicians
service, maintenance, other field technicians
service, maintenance, other field technicians
installation technicians
logistics department
commissioning engineer
EQUIPMENT STAGES RELEVANT PERSONNEL EXAMPLE ACTIVITIES
§ equipment design and development
§ conformity to regulations and standards
§ risk analysis concepts§ product safety testing
§ production and manufacture§ sample testing
§ storage of products and parts§ transportation
§ installation of equipment§ refrigerant handling
§ checking installation§ functional testing
§ service and maintenance practices
§ refrigerant handling§ retrofitting and workshop
conversions
§ decommissioning and disposal
§ refrigerant handling
maintenance
General approach for confirming safety
Establish conditions
Conformity to safety standards
Specific risk assessment
Particularly applicable to
mass-produced products
Direct use of risk assessment if standards are inadequate
Relevant safety standards for subsectors
SectorIEC
60335-2-24
IEC 60335-2-
40
IEC 60335-2-
89ISO 5149
ISO 13043
EN 378
Domestic refrigeration ×
Commercial refrigeration × × ×
Industrial systems × ×
Transport refrigeration × ×
Air-to-air air conditioners × × ×
Water heating heat pumps × × ×
Chillers × × ×
Vehicle air conditioning ×
Obligations for new refrigerants
Greater flammability Greater toxicity Greater pressure Stricter limits on the
quantity of refrigerant in occupied spaces
Use of gas detection, alarms and emergency ventilation
Prohibition of items that could act as sources of ignition
Warnings/signage
Stricter limits on the quantity of refrigerant in occupied spaces
Limited use in more densely populated areas
Use of gas detection, alarms and emergency ventilation
Provision of personal protective equipment
Thicker materials/higher pressure rating for pipes and components
Additional use of pressure relief devices and/or pressure limiting devices
Higher competencies for workers involved in construction of components and assemblies
Occupancy type
Seve
rity
of re
quire
men
ts
Direct systems
Indirect systems
a
mor
e se
vere
Less
sev
ere
Trained, controlledRandom, uncontrolled
b c unoccupied
Impact of system and occupancy on design
STEP 1: Avoidance of excessive pressurerelease
Identification of dangerous substances
Characterise the maximum achievable pressure
Construct system to withstand maximum pressure
STEP 2:Elimination of causes ofexcessive pressure rise
Identification of possible adverse causes leading to higher pressure
Eliminate causes or apply devices to avoid excessive pressure rise
STEP 3:Limiting theconsequencesof excessivepressure
Estimate the severity of excessive pressure
Adopt devices to alleviate unintended excessive pressure
STEP 1: Avoidance of toxic atmospheres
Identification of dangerous substances
Characterise possibility of toxic regions
Limit the extent of toxic regions
STEP 2:Elimination of contact with persons
Identification of possible recipients of exposure to toxic gas
Eliminate or protection of persons that may be exposed
STEP 3:Limiting theconsequencesof exposure
Estimate the severity of consequences of exposure
Adopt features to minimise the extent or duration of exposure
STEP 1: Avoidance of flammable atmospheres
Identification of dangerous substances
Characterise possibility of flammable regions
Limit the extent of flammable regions
STEP 2:Elimination of ignitionsources
Identification of potential sources of ignition
Eliminate or protection of potential sources of ignition
STEP 3:Limiting theconsequencesof ignition
Estimate the severity of consequences
Adopt features to minimise the severity of ignition
General risk assessment
For flammability
For high pressure
For toxicity
Topics for training
Topics FlammableHigher toxicity
Higher pressure
Basic principles
How to carry out flammability risk assessment for systems and installations X
How to carry out toxicity risk assessment for systems and installations X
How to carry out elevated pressure risk assessment for systems and installations X
Awareness of material safety data sheets (MSDS) X X X
Flammability characteristics (“fire triangle”, LFL, ignition energy, heat of combustion, etc) X
Toxicity characteristics (short term, long term, physiological effects, etc) X
Relevant safety standards and regulations that relate to equipment using flammable, higher toxicity and higher pressure gases X X X
Differences in refrigerant density compared to ordinary refrigerants and the implications on charge size and cylinder filling X
Differences in refrigerant pressure compared to ordinary refrigerants and the implications on system design pressure and size and cylinder pressure ratings X
Behaviour of a leak of refrigerant under different circumstances, i.e., the flow of denser-(or lighter-) than-air gas in closed rooms, enclosures, the outside in still or windy conditions and the effect of ventilation X X
System design and construction
Classifications within refrigeration safety standard – flammability, toxicity, occupancies, locations, system types X X X
Requirements of safety standards – determination of charge size limits (or minimum room sizes), need for safety devices (such as pressure limiters, pressure relief, etc), gas detection, ventilation, etc X X X
Sources of ignition; types of ignition sources, spark energies, temperature effects, etc X
Need for and types of protection appropriate for potential sources of ignition X
Importance of leak minimisation and methods for avoiding leakage X X X
Information requirements such as equipment marking, labelling and signage X X X
Working practices
How to carry out a risk assessment for creating and maintaining a safe working area and for carrying out work on a system containing flammable refrigerants X
How to carry out a risk assessment for creating and maintaining a safe working area and for carrying out work on a system containing higher toxicity refrigerants X
How to carry out a risk assessment for creating and maintaining a safe working area and for carrying out work on a system containing higher pressure refrigerants X
Selection and use of appropriate tools, equipment and personal protective equipment (PPE) when handling flammable, higher toxicity or higher pressure refrigerants X X X
Appropriate use of fire extinguishers X
Standard procedures for safe charging, recovery, evacuation, venting, etc X X X
Emergency response procedures, such as in the event of a major release or a fire or carrying out first aid X X X
Provision of relevant information for data-plates, equipment documentation and owners/operators X X
Selection of appropriate ‘like for like’ replacement components for electrical devices, electrical enclosures, compressors, etc., and maintaining the integrity of sealed electrical enclosures X
Presence and absence of odorant X
Restriction on relocation of existing systems/equipment X X X
Equipment for service and maintenance
Final remarks
Daniel Colbourned.colbourne@re-phridge.co.uk
Thank you for your attention!
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