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  2. Significant New Alternatives Policy (SNAP)

Compositions of Refrigerant Blends

The following tables show the percentage composition of refrigerant blends found acceptableThis 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 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 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 NameASHRAEASHRAE 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. NumberHCFCsCompounds 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.HFCsCompounds 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).HCsHFOsPFCsA 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.
22124142b2332125134a143a152a227eaEthane
(R-170)
Propane
(R-290)
n-Butane
(R-600)
Isobutane 
(R-600a)
Propylene
(R-1270)
IsopentaneHFO-1234yfHFO-1234ze(E)PFC-116
(perfluoro-ethane)
PFC-218
(perfluoro-propane)
MP-39R-401A5334      13           
MP-66R-401B6128      11           
MP-52R-401C3352      15           
HP-80R-402A38    60     2        
HP-81R-402B60    38     2        
R-403BR-403B56          5       39
HP-62, FX-70R-404A     44452            
GHGR-406A55 41          4      
KLEA 60, KLEA 407AR-407A    204040             
KLEA 407BR-407B    107020             
KLEA 407C, AC9000R-407C    232552             
 R-407D    151570             
Genetron Performax LTR-407F    303040             
FX-10R-408A47    7 46            
FX-56R-409A602515                 
AZ-20, Puron, Suva 9100R-410A    5050              
AC9100R-410B    4555              
R-411AR-411A87.5       11     1.5     
R-411BR-411B94       3     3     
GHG-X4R-414A5128.516.5          4      
Hot ShotR-414B50399.5          1.5      
NU-22/ISCEON 59R-417A     46.650     3.4       
Choice RefrigerantR-420A  12   88             
Choice R421AR-421A     5842             
Choice 421BR-421B     8515             
ISCEON 79R-422A     85.111.5      3.4      
ICOR XAC1R-422B     5542      3      
ICOR XLT1R-422C     8215      3      
ISCEON MO29R-422D     65.131.5      3.4      
RS-44 (new composition)R-424A     50.547     10.9 0.6    
RS-24 (new composition)R-426A     5.193     1.30.6      
Forane 427AR-427A    15255010            
RS-52R-428A     77.5 20   0.6 1.9      
RS-45R-434A     63.21618     2.8      
KDD5, ISCEON MO99R-438A    8.54544.2     1.7  0.6    
HCR-188CR-441A          3.154.836.16      
RS-50R-442A    313130 35          
Solstice® N-40R-448A    262621         207  
Opteon® XP-40R-449A    24.324.725.7         25.3   
Solstice® N-13R-450A      42          58  
AZ-50R-507A     50 50            
Klea 5R3R-508A   39              61 
Suva 95R-508B   46              54 
Opteon® XP-10R-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      19.578.8     1.7       
ICOR AT22      5542.5    1 1.5      
KDD6 Claimed as CBI
NARM-502 90  5    5           
Contact Us About the Significant New Alternatives Policy (SNAP) to ask a question, provide feedback, or report a problem.
Last updated on March 30, 2026
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