Effectiveness of Engineering Controls for Airborne Lead Exposure during Renovation/Demolition of a Commercial Building

Abstract

Airborne lead exposure was evaluated during renovation/demolition of a building that contained lead-based paint (LBP). During this work, different engineering and work practice controls were utilized for prevention and reduction of worker exposure to lead. These results suggest that the highest exposure occurred when no engineering or work practice controls were employed. Summary exposure levels under these conditions exceeded the Occupational Safety and Health Administration (OSHA) Permissible Exposure Level (PEL). When engineering/work practice controls, in the form of negative air machine filtration (NAM) and wet methods were used, airborne concentrations of lead were well below the OSHA PEL (50 µg·m^–3) and action level (30 µg·m^–3). Employment of NAM without wet methods reduced arithmetic mean exposure below the OSHA PEL and geometric mean below the OSHA action level. Occupational exposure concentration with NAM/wet methods was statistically lower when compared to no NAM/no wet methods and NAM/no wet methods. Exposure concentrations exhibited a nonnormal distribution. Comparison of within and between-worker variability suggests that process/environmental conditions (engineering/work practice controls) govern exposure. This study suggests employment of engineering and work practice controls for lead abatement and that process or environmental controls as compared to individual work practices/tasks are most important in controlling exposure. Study results support employment of NAM/wet method controls during renovation or demolition of building materials that contain LBP.

A Suggested Lead Surface Concentration Standard for Final Clearance of Floors in Commercial and Industrial Buildings

“…It has been suggested that lead loading is non-normally distributed, but BLL is normally distributed [16]. Summation of exposure data may be best represented as a geometric value (mean) [1,7]. that there is no relationship between the surface sampling methods, wipe and vacuum [21], if these proposed standards are applied the sampling method must be uniform and not interchanged.…”

“…Lead abatement is developing into a separate environment industry in the United States [1][2][3][4][5][6]. This is a result of the risks associated with use of the heavy metal lead in building materials and subsequent regulations controlling exposure associated with building materials [7,8].…”

“…Regulatory agencies considered the major route of exposure to children to be hand-to-mouth activities (pica) with inhalation a second but also important route [9,10]. Conversely, occupational exposure to lead, from a regulatory perspective, has focused on inhalation [1,[4][5][6]. This has resulted in two sets of proposed standards.…”

“…Employment of these 'HUD/EPA' criteria for commercial structures would appear not to be appropriate [1,18]. OSHA standards are also not applicable since these criteria were established primarily for those performing lead abatement and are related to inhalation exposure [1].…”

Toxicological analysis of ambient monitoring in metal industry

“…permissible exposure limit -PEL), koja je za Singapur 0,15 mg/m 3 (150 µg/m 3 ) i veća je tri puta od one koju propisuje OSHA (50 µg/m 3 ). Pri analizi samo jednog uzorka, vrlo je verovatno da postoji velika varijacija date vrednosti, što zahteva ispitivanje većeg broja uzoraka [19].…”