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Chlorodifluoromethane (R-22 or HCFC-22), a type of Freon. [9] [10] Dichlorodifluoromethane (R-12 or CFC-12), the most commonly used Freon brand refrigerant prior to its ban in many countries in 1996 and total ban in 2010. 1,1,1,2-Tetrafluoroethane (R-134a or HFC-134a), one of the main replacements for the formerly widespread R-12.
According to ASHRAE standard 34, the R-number of a chemical refrigerant is assigned systematically according to its molecular structure and has between two and four digits. If there are carbon -carbon multiple bonds , there are four digits in all: the number of these bonds is the first digit and the number of carbon atoms minus one (C-1) is next.
The first air conditioners and refrigerators employed toxic or flammable gases, such as ammonia, sulfur dioxide, methyl chloride, or propane, that could result in fatal accidents when they leaked. [4] In 1928 Thomas Midgley Jr. created the first non-flammable, non-toxic chlorofluorocarbon gas, Freon (R-12).
A special numbering system is to be used for fluorinated alkanes, prefixed with Freon-, R-, CFC- and HCFC-, where the rightmost value indicates the number of fluorine atoms, the next value to the left is the number of hydrogen atoms plus 1, and the next value to the left is the number of carbon atoms less one (zeroes are not stated), and the ...
Dichlorodifluoromethane (R-12) is a colorless gas popularly known by the genericized brand name Freon (as Freon-12). It is a chlorofluorocarbon halomethane (CFC) used as a refrigerant and aerosol spray propellant .
1-Chloro-1,1-difluoroethane (HCFC-142b) is a haloalkane with the chemical formula C H 3 C Cl F 2.It belongs to the hydrochlorofluorocarbon (HCFC) family of man-made compounds that contribute significantly to both ozone depletion and global warming when released into the environment.
Chlorodifluoromethane or Refrigerant gas R 22 UN 1019? (UN No. no longer in use) UN 1020: 2.2: Chloropentafluoroethane or Refrigerant gas R 115 UN 1021: 2.2: 1-Chloro-1,2,2,2-tetrafluoroethane or Refrigerant gas R 124 UN 1022: 2.2: Chlorotrifluoromethane or Refrigerant gas R 13 UN 1023: 2.3: Coal gas, compressed UN 1024 to 1025? (UN No.s no ...
Most are gases at room temperature and pressure. They are frequently used in air conditioning and as refrigerants ; R-134a (1,1,1,2-tetrafluoroethane) is one of the most commonly used HFC refrigerants .