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Respirator cartridge selection

Respirator cartridge selection

Find out in this section how to select the right gas mask filter. Respirator cartridges are used with half-mask respirators, full-face mask respirators or powered air purifying respirators (PAPRs) to filter contaminated air.

Filter selection tool
Gas selection	Corresponding filter cartridge

> Understanding coding

To select the proper filter cartridge for your gas mask, it is necessary to know the gas or substances that you want to be protected from.

Respirator cartridge - gas mask filter types codification

	A	Organic gas and vapor with boiling point above 65°C (solvents, hydrocarbons, alcohols, benzene, ethanol, freons/refrigerants, white spirit) dedicated respirator cartridge
	AX	Respirator cartridge for organic compound gas and vapor with boiling point below 65°C (many VOCs, methyl acetate, acetone, chloroform, methanol, phenol, styrene)
	B	Inorganic gas and vapor (hydrocyanic acid, bromine, chlorine, cyanide, chlorine dioxide, fluorine, hydrogen sulfide, carbon disulfide)
	CO	Carbon monoxide respirator cartridge
	E	Acid gas and vapor – mainly associated with P3 – (acrylic acid, formic acid, nitric acid, hydrogen chloride, sulfur dioxide, hydrogen fluoride)
	Hg	Mercury vapor and derivatives - mainly associated with P3 respirator cartridges
	K	Ammonia and organic derivatives (DMA, DMEA, hydrazine, methylamine, MMH, UMDS)
	Nox	Nitric oxide, nitrogen oxide, nitrous vapor
	REACTOR	Respirator cartridge against radioactive iodine, radioactive methyl iodine
	Sx	Specific manufacturer mentioned gas and vapor
	P	Solid and liquid particles (lead, asbestos, ceramic fibers, aerosols), highly toxic and radioactive particles, bacteria and viruses (bird flu, A/H1N1 flue, SRAS, tuberculosis, Ebola virus)

Major respirator cartridge filter combinations

Gas mask filter:	Protection from:
P	Solid and liquid particles, radioactive and highly toxic particles, bacteria and viruses
A2	Organic gas and vapor (solvent) with a boiling point above 65°C
B2	Inorganic gas and vapor (chlorine, hydrogen sulfide, hydrogen cyanide)
E2	Acid gas and vapor like sulfur dioxide
K2	Ammonia and organic derivatives
A2B2	Organic and inorganic gas and vapor
A2B2E2K2	Organic and inorganic gas and vapor, acid gas and vapor and ammonia
AX	Organic compound gas and vapor with a boiling point below 65°C
A2-P3	Organic gas and vapor (solvent) with a boiling point above 65°C, solid and liquid particles, highly toxic and radioactive particles, bacteria and viruses
B2-P3	Inorganic gas and vapor (chlorine, hydrogen sulfide, hydrogen cyanide), solid and liquid particles, highly toxic and radioactive particles, bacteria and viruses
E2-P3	Acid gas and vapor like sulfur dioxide, solid and liquid particles, highly toxic and radioactive particles, bacteria and viruses
K2-P3	Ammonia and organic derivatives of ammonia, solid and liquid particles, highly toxic and radioactive particles, bacteria and viruses
A2B2-P3	Organic and inorganic gas and vapor, solid and liquid particles, highly toxic and radioactive particles, bacteria and viruses
A2B2E1-P3	Acid, organic and inorganic gas and vapor, solid and liquid particles, highly toxic and radioactive particles, bacteria and viruses
A2B2E2K2-P3	Organic and inorganic gas and vapor, acid gas and vapor, ammonia, solid and liquid particles, highly toxic and radioactive particles, bacteria and viruses
AX-P3	Organic compound gas and vapor with a boiling point at or below 65°C, solid and liquid particles, highly toxic and radioactive particles, bacteria and viruses
Reactor-Hg-P3	Mercury and compounds, radioactive iodine and organic compound (methyl iodine), solid and liquid particles, highly toxic and radioactive particles, bacteria and viruses
A1E1Hg-P3	Acid, organic and inorganic gas and vapor, ammonia and organic derivatives, mercury vapor and compounds, solid and liquid particles, highly toxic and radioactive particles, bacteria and viruses
A2B2E2K2-Hg-P3	Acid, organic and inorganic gas and vapor, ammonia and organic derivatives, mercury vapor and compounds, solid and liquid particles, highly toxic and radioactive particles, bacteria and viruses
A2B2E2K1HgNOCO20-P3	Acid, organic and inorganic gas and vapor, ammonia and organic derivatives, mercury vapor and compounds, solid and liquid particles, highly toxic and radioactive particles, micro-organisms like bacteria and viruses

Filtering air purifying respirator usage limits

A filtering APR unit - gas mask or powered air purifying respirator equipped with respirator cartridge - should not be used in the following situations:

When the oxygen rate is under 19%.
When working in a confined space or a poorly ventilated area like tunnels, tanks or boat slips
When the pollutant concentration is unknown or immediately dangerous to life or health (IDLH)
When the pollutant concentration exceeds the maximum allowed concentration of the filter

In these situations using a self contained respiratory protection, aslo known as atmosphere supplying respirators, is recommended.

Respirator cartridge selection

Filter selection tool

Respirator cartridge - gas mask filter types codification

Major respirator cartridge filter combinations

Filtering air purifying respirator usage limits