I'm not on a hazmat team, so I need to clarify this question. When measuring an exposure to a chemical that has a PEL,and the PEL for that chemical (hydrogen Peroxide) is 1 do you divide the exposure by the actual time exposed. The way I read into the standard you would divide by 8 for a 8 hour work day. I had an employee that wore a dositube to measure exposure and over a 5 hour period she was exposed to 15PPM. Should the 15 be divided by 5, 8, or 40 for the work week? Thanks for any replys