Keywords: structural steel demolition, lead exposure, lead-, based paint, occupational exposure, residential renovation, acetylene torch cutting, welding, abrasive blasting, occupational health and safety
Occupational exposures to lead-based paint in structural steel demolition and residential renovation work
Occupational exposures to lead are characterised for a number of different lead-based paint abatement techniques in two work settings: residential renovation and structural steel demolition. Exposure levels reported during heavy structural steel demolition work involving acetylene torch cutting, welding, and abrasive blasting can be more than 100 times greater than the permissible exposure limit (PEL) set by the Occupational Safety and Health Administration (OSHA) for construction (200 µg/m³), which was in effect at the time of this study (the PEL was reduced to 50 µg/m³ in 1993). Surveillance data from an OSHA database for those standard industry classification (SIC) codes with a potential for exposure to lead-based paint in construction show that 49% of the air samples collected by OSHA were greater than 200 µg/m³, suggesting widespread non-compliance. New occupational exposure data from lead-based paint abatement work in public and private housing are also presented. In one public housing development, personal exposures to lead particulates measured during open flame burning and uncontained powered sanding were found to be more than 5000 µg/m³. These findings are contrasted with exposures measured during lead-based paint abatement work performed in accordance with the lead-based paint guidelines released by the US Department of Housing and Urban Development, where exposures were all lower than 25 µg/m³. Data from another public housing abatement project, involving work on 400 dwelling units over a 15-month period, show that workers' blood lead levels did not increase by more than 5 µg/dl above the pre-employment baseline. Abatement techniques studied here include interior and exterior building component replacement and exterior paint-stripping using a needle gun equipped with a high efficiency particulate air (HEPA) vacuum dust containment system. The data presented here show that it is feasible to keep airborne lead exposures below 20 µg/m³ in residential lead hazard control work, and to establish medical removal protection at blood lead levels of 25 µg/dl. These findings should be considered as OSHA finalises its interim final rule for lead exposure in construction work.