Mechanical filter respirators are a class of respirator that removes particulates from the air using a filter that mechanically stops them from reaching the wearer's nose and mouth.
| Oil resistance | Rating | Description |
|---|---|---|
| Not oil resistant | N95 | Filters at least 95% of airborne particles |
| N99 | Filters at least 99% of airborne particles | |
| N100 | Filters at least 99.97% of airborne particles | |
| Oil resistant | R95 | Filters at least 95% of airborne particles |
| R99 | Filters at least 99% of airborne particles | |
| R100 | Filters at least 99.97% of airborne particles | |
| Oil proof | P95 | Filters at least 95% of airborne particles |
| P99 | Filters at least 99% of airborne particles | |
| P100 | Filters at least 99.97% of airborne particles |
According to 3M, respirators made according to the following standards are equivalent to US N95 or European FFP2 respirators "for filtering non-oil-based particles such as those resulting from wildfires, PM 2.5 air pollution, volcanic eruptions, or bioaerosols (e.g. viruses)":
