What does the P1 P2 P3 classes for protective half-masks mean?

What does the P1 P2 P3 classes for protective half-masks mean?

The half-masks are used to protect against atomised small-sized solid particles, such as dusts, smokes, mists (do not protect against gases). The protective half-masks, made of fabric, are classified into three filtration effectiveness classes:
P1 – retain about 80% of particles smaller than 2 micrometers
P2 – retain about 94% of particles smaller than 0,5 micrometer
P3 – retain about 99,95% of particles smaller than 0,5 micrometer
The protective half-masks of the P1, P2, P3 classes are tested in accordance with the requirements of the standard PN-EN 149:2001.

Class of filtrationMaximum concentration level of pollutants (MCL)Filtration efficiencyKind of aerosolPurpose
P1 4 x NDS 80% dust, smoke, mist agricultural and food industry, application in building sector, quarries, cement works, in the wood industry for soft woodworking; protects against dusts such as calcium carbonate, natural and synthetic graphite, gypsum, chalk, cement, plaster, marble, zinc oxide, plant pollens, cellulose, sulphur, cotton, ferrous metal filings, coal dust containing less than 10% of free silica
P2 10 x NDS 94% dust, smoke, mist asbestos, copper, barium, titanium, vanadium, chromium, manganese, hardwood, coal dust with free silica content exceeding 10%, mining industry, chemical industry, metallurgic industry (version with exhalation valve), for hard woodworking
P3 30 x NDS 97% dust, smoke, mist high concentration of respirable dusts, use when welding and soldering, protects against dusts containing: beryllium, antimony, arsenic, cadmium, cobalt, nickel, radium, strychnine, radioactive particles

It is worth knowing

The half-masks increase inhalation resistance. The longer they are used, the more difficult it is to breathe due to absorbed dusts. Furthermore, their effectiveness is reduced accordingly to the growth of carbon dioxide and water vapour between the half-mask bowl and face (so-called dead zone). The carbon dioxide concentration within the dead zone increases after every exhalation. The masks should be therefore often changed. The non-return exhalation valves, accelerating gas circulations, are used in order to improve the comfort of use. When considering the purchase of the dust mask, it is worth choosing these ones equipped with this facility.

The proper mask adherence is essential for the mask effectiveness and comfort of use. The lack of tightness of the half-mask on its border results in the increase of so-called total leak, and, as a consequence, the loss of the filtration effectiveness. The loss of the tightness can be caused e.g. by the user’s facial hair.


Högert Technik GmbH
Pariser Platz 6a
10117 Berlin, Niemcy

Distribution in Poland GTV
ul. Przejazdowa 21
05-800 Pruszków, Polska