Respirators are specifically designed for use in work applications where metal fumes may be present such as welding, brazing, grinding, metal pouring, and more. Each filter has at least 95% efficiency for protection against solid and liquid particles excluding those containing oil. Welding respirators are disposable and feature the 3M™ Cool Flow™ Exhalation Valve and welding web. Also available with a faceseal and ozone protection* and nuisance level** organic vapor relief. NIOSH approved.* 3M recommended for ozone protection up to 10 x OSHA PEL (Not NIOSH approved for ozone). **Nuisance level refers to concentrations not exceeding OSHA PEL or other applicable exposure limits, whichever is lower.