In the United States, the Occupational Safety and Health Administration has set a permissible exposure limit at 15 mg/m3 over an eight-hour time-weighted average, while the National Institute for Occupational Safety and Health recommends exposures no greater than 10 mg/m3 over an eight-hour time-weighted average.[6] These occupational exposure limits are protective values, given the IDLH concentration is set at 1500 mg/m3.[7]