Laboratory and hospital evaluation of four personal monitoring methods for glutaraldehyde in ambient air.

Four industrial hygiene monitoring methods were studied in the laboratory and in a hospital to evaluate their effectiveness in measuring glutaraldehyde concentrations in ambient air. The sampling devices evaluated included a silica gel tube, a direct reading handheld glutaraldehyde meter, a DNPH- (2,4-dinitrophenylhydrazine) impregnated passive diffusion badge, and a DNPH-impregnated filter cassette. The accuracy and precision of the different methods were determined in the laboratory. The methods were evaluated using dynamically generated glutaraldehyde air concentrations over the range of 0.05-0.4 ppm. The badge, silica gel tube, and filter cassette methods were found to be accurate under controlled laboratory conditions. The handheld meter did not respond to the glutaraldehyde test atmospheres. The methods were compared in a hospital environment. During the hospital study the performance of the handheld meter could not be demonstrated because the concentrations of glutaraldehyde were below or only slightly above the manufacturer's stated 0.03 ppm limit of detection. Statistically significant differences were found between the badge, silica gel tube, and filter cassette methods, but the differences were small enough to be acceptable for industrial hygiene monitoring.