How do You Know What Level Of Protection To Choose?

Disposable dust masks and cartridge filters usually indicate the level of protection by the letter P and a number:

  • P1: Suitable for use around mechanically generated mists and dusts from sanding, drilling and so forth.
  • P2:Suitable where thermally and mechanically generated mists, fumes (welding), dusts and smoke are present.
  • P3:For use around viruses, bacteria and highly toxic dust particles (only with a full face respirator).
  • The Respirator Protection Factor.

The physical and chemical properties of the contaminant, and its effects on the body, can be ascertained from the most current Material Safety Data Sheet (MSDS) from the supplier of the substance concerned.

Masks and filters that are going to be used for gas or vapour related tasks are rated by the gas or vapour type. This is represented by a letter to indicate its suitability for different types of harmful vapours, and then a number, which indicates the capacity to absorb the gas or vapour.

Dust Filter & Gas Filter Class
Type

Colour

(European/Aus/NZ)

Description
A

Organic vapours and gases with

boiling point 65°C and above

B

Inorganic vapours and gases

(excluding carbon/dioxide/monoxide)

E

Sulphur dioxide and other acidic

vapours and gases

K

Ammonia and ammonia derivatives

vapours and gases

ABEK

Combination filters (all of the above)

P  

Particulate filters

 

Classifications
  Particulate

Gas/Vapour

(Maximum concentration)

1 Low Efficency (80%) Low Capacity (1,000ppm)
2 Medium Efficiency (94%) Medium Capacity (5,000ppm)
3 High Effciency (99.95) High Capacity (10,000ppm)