Assessing hydrogen peroxide vapor exposure from hospital sterilizers.

This study examines the hydrogen peroxide concentrations measured near four models of hydrogen peroxide sterilizers, from two manufacturers, monitored in seven hospitals across the U.S. and Canada over several years. The results showed that the majority of sterilizers do not emit hazardous levels of hydrogen peroxide and none of them exceeded the OSHA PEL of 1 ppm (8-hr time-weighted average (TWA)), however several of the sterilizers exceeded 3 ppm, the short-term exposure limit in two states: Washington and Hawaii. One hospital found brief concentrations of 25-40 ppm hydrogen peroxide from 4 hydrogen peroxide sterilizers each time they opened the sterilizer at the end of its cycle. Although not exceeding the OSHA PEL, these exposures are of concern since this concentration is roughly half the NIOSH IDLH of 75 ppm, and operators in a busy hospital environment may receive these exposures multiple times a day.