NIOSH approved for chlorine, hydrogen chloride, sulfur dioxide, chlorine dioxide, hydrogen fluoride and hydrogen sulfide. For use against particulates when no oil is present use with 8910 N95 Pre-Filter and 7020 retainer. For use against particulates when oil is present use with 8970 N95 Pre-Filter and 7020 retainer. For contaminants that fall under an OSHA substance specific standard requiring a high efficiency particulate air (HEPA) filter use with 7940 P100 filter disk and 7920 Piggyback adapter.