A field comparison of methods for monitoring ethylene oxide concentration.
Cummins-K; Burroughs-GE; Tremblay-J
Appl Occup Environ Hyg 1993 May; 8(5):463-471
A field evaluation of techniques for monitoring ethylene-oxide (75218) exposure was conducted. Crystal Diagnostics AirScan (AirScan) and 3M 3551-badges, hydrobromic-acid coated sorbent tubes, and two types of portable gas chromatographs were evaluated. The AirScan and 3M badges were passive diffusion devices. The sorbent tube was used in conjunction with a portable battery powered sampling pump. The gas chromatographs used a photoionization detector. The monitoring systems were tested in parallel at two commercial sterilization facilities that used ethylene-oxide to sterilize medical supplies. Fifteen minute and 8 hour time weighted average (TWA) exposure concentrations were measured. The performance of the systems were compared with each other as the actual ethylene-oxide concentrations in the facilities were not known. Overall 15 minute ethylene-oxide exposures at both sites ranged from 0.7 to 32 parts per million (ppm). The 8 hour TWA exposures ranged from 0.5 to 1.6ppm. Ethylene-oxide concentrations measured by the AirScan monitor at one site were significantly higher than those measured by the sorbent tube, but neither could be distinguished from the other three methods. Data obtained by all methods at the second facility did not differ significantly from each other, except for a set of 3M badges analyzed by one of two contract laboratories which found lower ethylene-oxide concentrations. The relative standard deviations (RSDs) in the data obtained by the gas chromatographs, sorbent tube, and 3M badge ranged from 0.7 to around 7%. The RSDs in data obtained by the AirScan monitors at the two facilities averaged 13.7 and 16.07%. The authors conclude that although the AirScan monitor is less precise than the other methods, all four monitoring methods provide statistically equivalent measures of short term and full shift ethylene-oxide exposures.
NIOSH-Author; Air-monitoring; Epoxides; Industrial-hygiene; Equipment-reliability; Air-sampling-equipment; Workplace-monitoring; Toxic-gases
Applied Occupational and Environmental Hygiene