Phenyl Mercuric Acetate (PMA): Mercury-Bearing Flexible Gymnasium Floors in Schools — Evaluation of Hazards and Controlled Abatement

Abstract

Phenyl mercuric acetate (PMA) historically has been used as a catalyst in polyurethane systems. In the 1950s–1970s, PMA was used as a catalyst in the 3M Tartan brand polyurethane flexible floors that were installed commonly in school gymnasiums. Mercury vapor is released into air above the surface of these floors. Sampling mercury in bulk flooring material and mercury vapor in air was conducted in nine Idaho schools in the spring of 2006. These evaluations were conducted in response to concerns by school officials that the floors could contain mercury and could release the mercury vapor into the air, presenting a potential health hazard for students, staff, and visitors. Controlled abatement was conducted in one school where remodeling would impact the mercury-bearing flexible gym floors (∼9,000 ft 2 total). The controlled abatement consisted of containment of the work area with negative air technology; worker protection, including mercury-specific training, use of personal protective equipment, and biological and exposure monitoring; and environmental protection, including proper disposal of mercury-bearing hazardous waste material.