In-depth survey report: evaluation of control technology for perchloroethylene in dry cleaning shops at Ten Ten Cleaners, San Francisco, California, report no. EPHB-240-12.
NIOSH 2000 Mar; :1-15
NIOSH evaluated eight dry cleaning shops to determine the extent of exposure and the technological feasibility of controlling worker exposure to perchloroethylene (Perc). In this study, dry cleaning plants were selected and data taken to characterize worker exposure levels and control technology for "fourth generation" closed-loop, dry-to-dry machines (with an integrated, in-line refrigerated condenser and a carbon absorber to recover Perc vapors during the dry cycle), and "fifth generation" machines, having the same features as fourth generation machines plus an internal monitor/interlock system to prevent door opening at Perc concentrations above a set level. Full shift time-weighted average (TWA) and short duration Ceiling and 15 minute Short Term Exposure Level (STEL) Perc exposures were measured on several workers in each shop. Information was collected at each dry cleaning plant to correlate Perc measurements with controls and equipment. Results of measurements at Ten Ten Cleaners indicate a range of <0.008 to 0.59 ppm for full shift charcoal tube measurements Data gathered at the eight dry cleaning shops monitored indicate that in almost all instances the full shift TWA concentration of Perc were below the 5 to 10 ppm range STEL and Ceiling measurements at Ten Ten Cleaners ranged from 0.5 to 7.3 ppm for STEL measurements and 9 to 620 ppm for Ceiling values. The comparable range for the set of eight shops was 2 to >2,000 ppm and 0.2 to 60 ppm, with half the measurements of Ceiling and STEL levels below 168 ppm and 4.2 ppm, respectively.
Region-9; Control-technology; Dry-cleaning-industry; Dry-cleaning-solvents; Chlorinated-hydrocarbons; Occupational-exposure; Engineering-controls
Control Technology; Field Studies
NTIS Accession No.
National Institute for Occupational Safety and Health