![]() Unfortunately the right idea of formaldehyde exposure monitoring collides with fear that is not the best adviser to common sense. Nobody wants to take chances to deal with the regulatory governmental institutions. It was a simple explanation as splashing that could contaminate the sample badge, but the management became so agitated that a special consulting firm was invited, with many days of monitoring performances, meetings, and papers. Nobody on this day reported any odors that would be consistent with high formaldehyde exposures. One was 10 ppm while another showed 0.055 ppm. Recently, during annual monitoring, personal samples at two grossing stations collected on the same day near each other came back with different readings. I always resisted temptation to repeat intentionally this “experiment.” I haven’t done this for good reasons that show the second story. I do not have any explanation why the reading came normal. I left once by accident a monitoring badge overnight on my coat near buckets with formalin, but somebody for some reasons open the lid. Two personal stories reflect the relative value of this monitoring.īeing “soaked” by formalin for many years, my annual monitoring had never reviled any abnormal reading. The most important is that surgical pathology handles 10% Formalin, but not formaldehyde as emanating gas. Actually, they are not necessary to use in laboratory practice, although they are reasonable in industrial setting because there might be additional factors which can be combined with formaldehyde (industrial dust, metallic particles, etc.). I my opinion, ACGIH limits are not attainable in the surgical pathology laboratory. It is remarkable that the ACGIH 0.3 ppm limit is set on irritation, not carcinogenicity. The American Conference of Governmental Industrial Hygienists (ACGIH) has more stricter requirements for time weighted average (TWA) short-term-exposure limit (STEL) (0.3 ppm) than OSHA (2 ppm), although the recommended exposure limits do not have a legal application in the USA in opposite to OSHA. ![]() The badges are portable, for example provided by Advanced Chemical Sensors, Inc. Usually monitoring is done on annual basis. ![]() Determination time-weighted average (TWA) collected from the employee’s breathing zone air during full shift is considered as optimal. A “representative employee” is asked to wear a sampling passive badge device to collect formaldehyde (industrial monitoring uses a different methodology). OSHA requires monitoring by the employer of the exposure to formaldehyde exceeds the 0.5 ppm (the Action Level) or the 2.00ppm STEL. The limit for airborne exposure to formaldehyde set by OSHA the Formaldehyde Standard (TWA) is 0.75 ppm in an 8-hour time-weighted average (officially 1 ppm) and 2 ppm for a 15-minute Short-Term Exposure Limit (OSHA STEL). According to OSHA odor threshold is 0.8-1 ppm. ![]() The threshold for subjective effects varies considerably from 0.1 to 2.5 ppm most people feel symptoms in the throat first. ![]()
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