in this research, air sampling of workplaces was carried out by two methods (long - time and short - time). the mean formaldehyde concentration with long - time method in pathology labs, surgery and endoscopy sections were 0.96 0.25 and 0.13 ppm and with short - time method, 8 hours, was 3, 0.3 and 0.2 ppm. the mean formaldehyde concentration in pathology labs was above the standard values (tlv...