Cost evaluation of control measures for indoor radon progeny.

Based on assumed conditions within a typical U.S. home, annualized costs for reducing indoor airborne radon progeny concentrations have been calculated for a variety of methods of control. These analyses were limited to methods for control in existing homes. Control through modified construction techniques was not evaluated. Methods assessed included increased air circulation, increased ventilation, particle removal using electrostatic precipitation and unipolar ion generation, and the application of sealants to room surfaces. Although surface sealants proved to be reasonably cost-effective per person- sievert dose reduction, such sealants are prone to cracking and the durability of their effectiveness is questionable. Use of ceiling fans for increased air circulation and particle deposition appears to be least cost-effective, but this method may be attractive in some cases for reasons of comfort. The use of unipolar ion generators appears to be the best approach from the standpoint of cost effectiveness. These devices are also easy to install and are esthetically readily acceptable.