Foam sealants have revolutionized home insulation and weatherization. They now fulfill a long list of tasks: sealing window and door jambs, sealing wiring and pipe penetrations through the building shell, and most recently, sealing out radon from basements. Occasionally, the sealants have even been used to insulate the upper sections of foundation walls and the backs of spas and pools. Unfortunately, foam sealants are aerosols and use chlorofluorocarbons (CFCs) as foaming agents. CFCs have been linked to ozone depletion, and restrictions on their production went into effect on January 1, 1989. The foam sealant industry is waiting for major chemical manufacturers to find alternative foaming agents, but one manufacturer has already introduced an "ozone-friendly" foam sealant. I've tested it and I'll give