"In the field of health care, gaseous chlorine dioxide should be further promoted." "The concentration of the 8 h weighted concentration value (0.28 mg/m3) was exposed for a long time to achieve the purpose of eliminating common indoor bacteria. In the case of killing bacterial spores, higher relative humidity is required, generally not less than 60% RH. The higher relative humidity can wet the outer wall of the spore to expand it to facilitate the attachment and penetration of gaseous chlorine dioxide, while the high humidity environment increases the risk of corrosion of gaseous chlorine dioxide"

***** {Calculation methods for air concentrations of gas in ppm"the OSHA PEL in mg/m3 is absolutely fixed and not subject to corrections for temperature and pressure." "This constraint implies that volume concentration of gases in parts per million (ppm) must be with reference to some defined temperature and pressure; these are NTP (25 °C and 760 mm Hg) in the OSHA PEL limit."

" I have assumed that you are speaking to the permissible exposure limit (PEL) for a single air contaminant over an extended workshift rather than calculating a PEL for multiple chemical exposures with synergistic or additive effects. OSHA has only two standards that specifically allow an adjustment to the PEL based upon the number of hours worked. Those two standards include 29 CFR 1910.1025 and 1926.62 - both for occupational lead exposure. No other OSHA PEL has taken this approach. All of the other OSHA PELs are based upon an 8-hour time weighted average (TWA) exposure limit, a short term exposure limit (STEL) or a ceiling exposure limit. Some contaminants may have multiple exposure limits depending upon the nature of the hazardous chemical."