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Significant New Alternatives Policy (SNAP)

Compositions of Refrigerant Blends

The following tables show the percentage composition of refrigerant blends found acceptableHelpacceptableThis designation means that a substitute may be used, without restriction, to replace the relevant ODS within the end-use specified. For example, HCFC-22 is an acceptable substitute for R-502 in industrial process refrigeration. Note that all SNAP determinations apply to the use of a specific product as a substitute for a specific ODS in a specific end-use.acceptable subject to narrowed use limitsHelpacceptable subject to narrowed use limitsThis designation indicates means that a substitute would be unacceptable unless its use was restricted to specific applications within an end-use. This designation is generally used when the specific characteristics of different applications within an end-use result in differences in risk. Use of the substitute in the end-use is legal only in those applications included within the narrowed use limit. Note that all SNAP determinations apply to the use of a specific product as a substitute for a specific ODS in a specific end-use., or acceptable subject to use conditionsHelpacceptable subject to use conditionsThis designation means that a substitute would be unacceptable unless it is used under certain conditions. An example is the set of use conditions placed on motor vehicle air conditioning refrigerants, requiring the use of unique fittings and labels and requiring that the original refrigerant be removed before charging with an alternative. Use of the substitute in the end-use is legal provided the conditions are fully met. Note that all SNAP determinations apply to the use of a specific product as a substitute for a specific ODS in a specific end-use.. The specific determinations that apply to these blends are listed by end-use.

Percentage Composition of Substitute Refrigerant Blends

Trade Name ASHRAEHelpASHRAEASHRAE is an international organization that establishes standards for the uniform testing and rating of heating, ventilation, air conditioning, and refrigeration equipment. It also conducts related research, disseminates publications, and provides continuing education to its members. Number HCFCsHelpHCFCsCompounds containing hydrogen, fluorine, chlorine, and carbon atoms. Although ozone depleting substances, they are less potent at destroying stratospheric ozone than chlorofluorocarbons (CFCs). They have been introduced as temporary replacements for CFCs and are also greenhouse gases. See ozone depleting substance. HFCsHelpHFCsCompounds containing only hydrogen, fluorine, and carbon atoms. They were introduced as alternatives to ozone depleting substances in serving many industrial, commercial, and personal needs. HFCs are emitted as by-products of industrial processes and are also used in manufacturing. They do not significantly deplete the stratospheric ozone layer, but they are powerful greenhouse gases with global warming potentials ranging from 140 (HFC-152a) to 11,700 (HFC-23). HCs HFOs PFCsHelpPFCsA group of human-made chemicals composed of carbon and fluorine only. These chemicals (predominantly CF4 and C2F6) were introduced as alternatives, along with hydrofluorocarbons, to the ozone depleting substances. In addition, PFCs are emitted as by-products of industrial processes and are also used in manufacturing. PFCs do not harm the stratospheric ozone layer, but they are powerful greenhouse gases: CF4 has a global warming potential (GWP) of 6,500 and C2F6 has a GWP of 9,200.
22 124 142b 23 32 125 134a 143a 152a 227ea Ethane
(R-170)
Propane
(R-290)
n-Butane
(R-600)
Isobutane 
(R-600a)
Propylene
(R-1270)
Isopentane HFO-1234yf HFO-1234ze(E) PFC-116
(perfluoro-ethane)
PFC-218
(perfluoro-propane)
MP-39 R-401A 53 34             13                      
MP-66 R-401B 61 28             11                      
MP-52 R-401C 33 52             15                      
HP-80 R-402A 38         60           2                
HP-81 R-402B 60         38           2                
R-403B R-403B 56                     5               39
HP-62, FX-70 R-404A           44 4 52                        
GHG R-406A 55   41                     4            
KLEA 60, KLEA 407A R-407A         20 40 40                          
KLEA 407B R-407B         10 70 20                          
KLEA 407C, AC9000 R-407C         23 25 52                          
  R-407D         15 15 70                          
Genetron Performax LT R-407F         30 30 40                          
FX-10 R-408A 47         7   46                        
FX-56 R-409A 60 25 15                                  
AZ-20, Puron, Suva 9100 R-410A         50 50                            
AC9100 R-410B         45 55                            
R-411A R-411A 87.5               11           1.5          
R-411B R-411B 94               3           3          
GHG-X4 R-414A 51 28.5 16.5                     4            
Hot Shot R-414B 50 39 9.5                     1.5            
NU-22/ISCEON 59 R-417A           46.6 50           3.4              
Choice Refrigerant R-420A     12       88                          
Choice R421A R-421A           58 42                          
Choice 421B R-421B           85 15                          
ISCEON 79 R-422A           85.1 11.5             3.4            
ICOR XAC1 R-422B           55 42             3            
ICOR XLT1 R-422C           82 15             3            
ISCEON MO29 R-422D           65.1 31.5             3.4            
RS-44 (new composition) R-424A           50.5 47           1 0.9   0.6        
RS-24 (new composition) R-426A           5.1 93           1.3 0.6            
Forane 427A R-427A         15 25 50 10                        
RS-52 R-428A           77.5   20       0.6   1.9            
RS-45 R-434A           63.2 16 18           2.8            
KDD5, ISCEON MO99 R-438A         8.5 45 44.2           1.7     0.6        
HCR-188C R-441A                     3.1 54.8 36.1 6            
RS-50 R-442A         31 31 30   3 5                    
Solstice® N-40 R-448A         26 26 21                   20 7    
Opteon® XP-40 R-449A         24.3 24.7 25.7                   25.3      
Solstice® N-13 R-450A             42                     58    
AZ-50 R-507A           50   50                        
Klea 5R3 R-508A       39                             61  
Suva 95 R-508B       46                             54  
Opteon® XP-10 R-513A             44                   56      
Free Zone 
(2% is a lubricant)
      19       79                          
Freeze 12       20       80                          
FRIGC FR-12     39         59           2              
G2018C   95.5               1.5           3          
GHG-HP   65   31                     4            
GHG-X5   41   15             40       4            
Hot Shot 2             19.5 78.8           1.7              
ICOR AT22             55 42.5         1   1.5            
KDD6   Claimed as CBI
NARM-502   90     5         5