Survey report: control technology evaluation for controlling worker exposure to asphalt fumes from roofing kettles: kettle operated using an afterburner system at Jo and George Marti Elementary School, Cleburne Independent Schools, 2020 West Kilpatrick St., Cleburne, Texas, report no. CT-231-15a.
NIOSH 2004 Mar; :1-23
On February 4, 5, 11, 12, 18, and 19, 2003, a field survey was conducted at a construction site where a built up asphalt roof was being install on Jo and George Marti Elementary School in Cleburne, Texas. The school was a new school under construction. The survey was conducted to evaluate the effectiveness of using an afterburner system with a safety loading door fitted to an asphalt kettle to reduce worker exposure to asphalt fumes. Personal breathing zone and area air samples were collected and analyzed for total particulate (TP), benzene soluble fraction (BSF) of the TP, and total polycyclic aromatic compounds (PAC). These three analyses were chosen to represent indices of exposure to asphalt fumes. Air samples were collected with the afterburners on and kettle lid closed and the afterburner off and kettle lid closed. Air samples were collected on the kettle operator, two roof level workers, and area air samples collected around the four comers of the kettle. Only the kettle operator's exposure to TP was reduced (74%) when the afterburner was on and the kettle lid was closed when compared to when the afterburner was off and the kettle lid was opened. Exposures to BSF and total PAC for the kettle operator increased 17% and 21 % for BSF and total PAC when the afterburner was on and the kettle lid was closed when compared to when the afterburner was off and the kettle lid was opened. Reductions of 74%, 84%, and 81 % in TP, BSF, and total PAC were measured for the area air samples collected around the kettle when the afterburner was on and the kettle lid was closed when compared to when the afterburner was off and the kettle lid was closed. For the roof level workers, exposures to TP, BSF, and total PAC increased 275%, 287%, and 142%, respectively, when the afterburner was on and the kettle lid was closed when compared to when the afterburner was off and the kettle lid was closed. None of the reductions measured were statistically significant (p less than or equal to 0.05). Although the results generally did not show a statistically significant reduction in exposure to asphalt fumes, a 74% reduction in TP was measured for the kettle operator. This indicates that the afterburner did have some impact on operator exposure. The kettle operator's measured exposures to BSF and total PAC were higher when the afterburners were on. This may indicate that the exhaust for the afterburner needs to be redirected so that it does not enter the operator's breathing zone. The fact that reductions were seen in the area air sample results when the afterburners were on also indicates that a reduction in the kettle operator's exposures may decrease with the afterburners on if the exhaust was redirected. The increase in exposure for the roof level workers when the afterburners were on would seem to indicate that the afterburner has little effect in reducing their exposures to asphalt fumes.
Construction-materials; Construction-workers; Control-technology; Roofers; Air-sampling; Asphalt-fumes; Exposure-assessment; Exposure-levels; Breathing-zone; Region-6; Benzenes; Polycyclic-aromatic-hydrocarbons
National Institute for Occupational Safety and Health, Division of Applied Research and Technology, Mail stop R-5, 4676 Columbia Parkway, Cincinnati, OH 45226
Field Studies; Control Technology
NTIS Accession No.
Research Tools and Approaches: Control Technology and Personal Protective Equipment
National Institute for Occupational Safety and Health