"Chlorocarbons," or "chlorinated carbons," refers to hydrocarbons in which hydrogen atoms are replaced by chlorine atoms. We are concerned with seven chlorocarbons - four types of chlorinated C1 hydrocarbons (methane family) and three types of chlorinated C2 hydrocarbons (ethane family).

C1 hydrocarbons:
 
 
 

C2 hydrocarbons:

Methyl chloride (chloromethane, etc.)
Methylene chloride (dichloromethane, etc.)
Chloroform (trichloromethane)
Carbon tetrachloride (tetrachloromethane)

Trichloroethylene
Tetrachloroethylene (perchloroethylene)
1,1,1-Trichloroethane (methyl chloroform)

Of these, carbon tetrachloride and 1,1,1-trichloroethane have been prohibited from being produced and consumed except for specific applications since January 1, 1996 by the "Law Concerning the Protection of the Ozone Layer through the Regulation of Specified Substances and Other Measures" based on the Montreal Protocol on Substances that Deplete the Ozone Layer. Thus, the substances that our association is presently concerned with are among the five chlorinated hydrocarbons listed above.