List of refrigerants

This is a list of refrigerants, sorted by their ASHRAE-designated numbers, commonly known as R numbers. Many modern refrigerants are human-made halogenated gases, especially fluorinated gases and chlorinated gases, that are frequently referred to as Freon (a registered trademark of Chemours).

Numbering scheme
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. If there is more than one carbon atom but no multiple bonds, there are three digits, and the number of carbon atoms minus one is the first digit. If there is only one carbon atom, then there are only two digits. The last two digits are always the number of hydrogen atoms plus one (H+1), followed by the number of fluorine atoms. Any other atoms attached to the carbons are assumed to be chlorine atoms. For example, R-22 has one carbon atom, one hydrogen atom (2−1 = 1), two fluorine atoms, and one chlorine atom (4−2−1 = 1), so it is chlorodifluoromethane, while R-134 has two carbon atoms (2−1 = 1), two hydrogen atoms (3−1 = 2), four fluorine atoms, and no chlorine atoms (6−2−4 = 0), so it is one of the tetrafluoroethanes. This basic scheme is modified as follows:
 * Capital letters "B" and "I" are suffixed, together with atom counts, if chlorine atoms have been replaced with bromine or iodine.
 * If there are two carbons, the isomer without suffix is the most symmetrical; after this, lower-case suffixed letters "a", "b", ..., are added, moving forwards through the alphabet as symmetry decreases.
 * If there are more than two carbons, a more complex system of suffixed letters and possibly numbers is used to distinguish isomers, when necessary.
 * The suffixes "(Z)" and "(E)" may be used to differentiate (Z)- and (E)- (cis- and trans-) isomers.
 * For larger molecules, numerical "digits" exceeding 9 may occur; in this case, these numbers are separated by dashes.
 * For a cyclic carbon skeleton, the prefixed capital letter "C" is used.
 * For an oxygen-containing refrigerant (an ether), the prefixed capital letter "E" is used.

There are separate numbering schemes for zeotropic and azeotropic blends, organic chemicals which don't fit into the scheme above, and inorganic chemicals:
 * Zeotropic blends are numbered starting with 400. Suffixed capital letters "A", "B", ... may be used to distinguish different blends with the same constitutents.
 * Azeotropic blends are numbered similarly to zeotropic blends, but starting with 500.
 * Other organic chemicals may be numbered starting with 600. Suffixed lowercase letters "a", "b", ..., may be used to distinguish isomers.
 * Inorganic chemicals are given numbers equalling 700 plus their molecular weight, if the weight is less than 100, or 7000 plus the molecular weight otherwise. Suffixed capital letters "A", "B", ... may be used to distinguish different chemicals with the same molecular weight.

Columns
The table is sortable by each of the following refrigerant properties (scroll right or reduce magnification to view more properties):
 * Type/prefix (see legends)
 * ASHRAE number
 * IUPAC chemical name
 * molecular formula
 * CAS registry number / blend name
 * Atmospheric lifetime in years
 * Semi-empirical ozone depletion potential, ODP (normalized to be 1 for R-11)
 * Net global warming potential, GWP, over a 100-year time horizon (normalized to be 1 for R-744, carbon dioxide)
 * Occupational exposure limit/permissible exposure limit in parts per million (volume per volume) over a time-weighted average (TWA) concentration for a normal eight-hour work day and a 40-hour work week
 * ASHRAE 34 safety group in toxicity & flammability (in air @ 60 °C, 101.3 kPa) classing (see legends)
 * Refrigerant concentration limit / immediately dangerous to life or health in parts per million (volume per volume) and grams per cubic meter
 * Molecular mass in atomic mass units
 * Normal boiling points for pure substances, bubble and dew points for zeotropic blends, or normal boiling point and azeotropic temperature for the azeotropic blends, at 101,325 Pa (1 atmosphere) and in degrees Celsius
 * Critical temperature in degrees Celsius
 * Absolute critical pressure in kilopascals

Since over 100,000 refrigerant blends are possible, this list should only have notable refrigerants and refrigerant blends.

Type and flammability
Compounds used as refrigerants may be described using either the appropriate prefix above or with the prefixes "R-" or "Refrigerant." Thus, CFC-12 may also be written as R-12 or Refrigerant 12. An alkene, olefin, or olefine is an unsaturated compound containing at least one carbon-carbon double bond.


 * Educated Estimates