Engineering controls for furniture strippers to meet the new OSHA PEL for methylene chloride.
Fairfield Estill C; Kurimo R; Watkins D
American Industrial Hygiene Conference and Exposition, May 20-25, 2000, Orlando, Florida. Fairfax, VA: American Industrial Hygiene Association, 2000 May; :39-40
OSHA recently lowered the permissible exposure limit (PEL) for methylene chloride to 25 ppm with an action level of 12.5 ppm. Small businesses are now required to use engineering controls to meet this standard. This research was conducted at a small furniture-stripping facility with one worker who strips furniture using a dip tank. In the mid-1980s, this facility was found to have exposures to methylene chloride as high as 2000 ppm. In 1991, engineering controls were installed at the dip tank, and exposures were reduced to 59 ppm. A follow-up survey in 1997, however, showed that exposures at this facility had increased to 74 ppm. In 1998 and 1999, to reduce the methylene chloride levels to below the OSHA standard, improvements were made. These included larger ducts, more gradual transition duct, new fan for the dip tank, ventilation system in the rinsing area, and paraffin wax in the stripping solution. Ten one-hour samples were collected on the left lapel in the employee's breathing zone. Area samples and bulk samples were also collected. The 10 breathing zone samples had a mean time-weighted average (TWA) concentration of 7.6 ppm and ranged from not detectable to 14.3 ppm. The mean breathing zone concentration was statistically less than the 1997 OSHA PEL of 25 ppm (t-test, df = 9, p = 0.01). For area samples, TWAs of 4.9, 8.1, and 6.1 ppm were found in the stripping, rinsing, and drying areas, respectively. Fifty-two percent of methylene chloride was found in the stripping solution and 0.03% was found in the rinsing water. The results from this survey show that worker exposures to methylene chloride while stripping furniture can be controlled below the 1997 OSHA PEL of 25 ppm.
Methyl-compounds; Chlorides; Permissible-concentration-limits; Exposure-levels; Exposure-limits; Small-businesses; Control-technology; Control-methods; Engineering-controls; Standards; Air-sampling; Air-quality-monitoring; Furniture-industry; Furniture-workers; Industrial-exposures; Industrial-hygiene-programs; Industrial-engineering; Ventilation-equipment; Ventilation-systems; Breathing-zone; Employee-exposure; Sampling; Time-weighted-average-exposure; Environmental-control-equipment; Work-environment; Paint-removers; Solvent-vapors; Solvents
American Industrial Hygiene Conference and Exposition, May 20-25, 2000, Orlando, Florida