Filters for half masks and full face masks provide protection against a range of hazardous substances. Particulate filters – also known as ‘dust filters’ – are used to protect against airborne particles, including dusts, fibres, mists and fumes. Particulate filters are classified by efficiency however the level of protection provided to the wearer can vary depending on the type of mask the filters are fitted to.

Filter classification

Particulate filters for half masks and full face masks are tested and certified to EN 143 which classifies filters based on efficiency:

- P1 – Low filter performance (80% minimum efficiency)
- P2 – Medium filter performance (94% minimum efficiency)
- P3 – High filter performance (99.95% minimum efficiency)

Assigned Protection Factors (APFs)

An Assigned Protection Factor (APF) refers to the level of protection that a wearer can reasonably expect from a respirator in the workplace. Different countries have varying APFs, and it is important to check local regulations prior to selecting equipment.

The type of mask that filters are fitted to can affect the APF provided by the equipment in combination. The APF provided by P3 filters fitted to a full face mask is higher than when fitted to a half mask.

A full risk assessment must be completed to determine the appropriate filter type and protection factor for a hazard or task. Half masks and full face masks are tight-fitting RPE, meaning fit testing is required. Find out more about fit testing. Contact JSP Technical for assistance in selecting respiratory protective equipment (RPE).

Learn more about selecting adequate and suitable RPE.
Find out more about RPE standards.