The 3M 8511 is NIOSH certified to have a filter efficiency of 95% or greater for non-oil based particulates. Made in the USA. This disposable N95 particulate respirator features the proprietary 3M™ Cool Flow™ Valve and helps provide comfortable, reliable worker respiratory protection. It is ideally suited for hot/dusty work settings that require long periods of wear. Use for solid particulates and liquid mists in concentrations not exceeding 10X PEL/OEL.