Gas mask filter

The efficiency of the filtering respiratory protection devices depends mainly on the choice of the filter following the gases, vapors, and particles present. According to the activity sectors and gases likely to be there, different gas mask filters guarantee efficient respiratory protection: particle filters (fine dust, aerosols, viruses, and bacteria), anti-gas filters (organic and inorganic vapors, acids, ammonia, and mercury vapors), combined filters (gas and particles), CO / NO filters and Reactor / Nuclear filters (Iodine 131 and radioactive methyl iodide).

Our range of gas mask filters

Filter selection tool

Gas selection

Corresponding filter cartridge

> Understanding coding
  1. Spasciani DIN Rd40 filters combine know-how and advanced technology in the filtration field. They are approved to the latest EN standards in force, marked "R" for reusable and with a standard thread EN 148-1 40mm and compatible with all full face masks approved EN 136 and half-masks approved EN 140.

    • Respiratory protection filters Rd40 DIN (Rd40 mm x 1/7") according to EN 148-1 marked "R" for reusable
    • Wide range of filters: particulate, anti-gas, Nuclear/Reactor, and CO/NO filters (ABEK-Hg-NO-CO20-P3)
    • Compatible with EN 136 full face masks and EN 140 half masks
    • Lightweight and durable polypropylene housing
    • Excellent quality/price ratio
  2. The Dräger X-plore Rd40 respiratory protection filters feature a universal 40 mm thread (complied with EN 148-1 standard) and offer efficient filtration against toxic substances, from organic vapors to radioactive iodine through acids and mercury. They are individually wrapped to ensure optimal protection even when they are not in use.

    • Respiratory protection filters Rd40 DIN (EN 148-1) compatible with EN 136 approved masks and EN 140 half masks
    • Wide range of filters: particulate, anti-gas, Nuclear/Reactor, and CO/NO filters (ABEK-Hg-NO-CO20-P3)
    • Aluminum housing for easy damage detection
    • Marked "R" for "Reusable"
    • Complies with EN 14387 and EN 143:2000 standards
  3. The CO / NO filters are "super cartridges" filtering particles and aerosols, organic and inorganic vapors, acids, ammonia and its derivatives, and mercury vapors. They filter especially carbon monoxide (CO) and nitrogen monoxide (NO), gases that are particularly difficult to filter due to their properties.

    • Filter CO / NO: protection against carbon monoxide and nitrogen monoxide in addition to maximum chemical protection
    • Respiratory protection filters Rd40 DIN (EN 148-1) compatible with EN 136-approved full face masks
    • Limited duration of use (20 minutes maximum)
    • Aluminium housing with interior treatment
    • Intended for evacuation from the danger zone
  4. Nuclear / Reactor filters are available in 2 filtration versions: A2-P3 Reactor and A2B2E2K1-P3 Reactor. They offer respiratory protection against radioactive particles, iodine 131, and radioactive iodomethane. Type Rd40 with a universal thread of 40mm, these filters fit all EN 136 approved full face masks, covering the entire face.

    • Nuclear / Reactor filter: Protection against radioactive particles, iodine 131 and radioactive methyl iodide
    • Respiratory protection filters Rd40 DIN (EN 148-1) compatible with full face masks approved EN 136
    • Available in two versions: A2-P3 Reactor and A2B2E2K1-P3 Reactor
    • Low breathing resistance: 2.1 mbar at 30 l/min
    • Propylene housing / Weight 265 grams
  5. CleanSpace filters cover a wide range of applications from the P3/HEPA filter against fine particles, aerosols, viruses and bacteria to the ABEK1-P3 filter for most tertiary applications, the A2-P3 filter for phytosanitary treatment or paint works or the AX-P2 filter against solvents and volatile organic compounds.

    • EN12942 certified high performance filters, fiberglass media and plastic casing with silicone seal
    • Filters for CleanSpace Pro: P3/HEPA, A2-P3, AX-P2, ABEK1-P3
    • Filters for CleanSpace Ultra: P3/HEPA, A2-P3, AX-P2, ABEK1-P3
    • Filters for the CleanSpace Ex (ATEX version): P3, A2-P3, ABEK1-P3 & AX-P2 (the only ATEX powered air unit on the market against VOCs)
    • Filters for the CleanSpace Halo (healthcare or food industry): P3/HEPA
  6. Compatible with Dräger bi-filters masks and half masks, the X-plore bayonet filters combine modern design and low breathing resistance to fit the most diverse applications. Their sideways positioning provides a broad and continuous field of vision and better weight distribution of the filters too.

    • Dräger X-plore bayonet filters for dual-filter masks (X-plore 3300, X-plore 3500, X-plore 5500)
    • Broad and continuous field of view and better filters weight distribution
    • Bayonet connection for easy and safe installation
    • Robust housing made of lightweight ABS plastic
    • Excellent price/performance ratio
  7. SCOTT Pro 2000 filters, combining lightness and low breathing resistance, are compatible with all full-face masks complying with the EN 136 standard and half masks complying with the EN 140 standard. The available range covers the entire field of respiratory filter application, all conforming to European standards and bearing the CE mark.

    • Respiratory protection filters Universal DIN 40 mm connection, by EN 148-1 standard
    • Compatible with full-face masks (EN 136) and half masks (EN 140)
    • Three ranges of filters: particulate, anti-gas, and combined filters
    • Large absorption surface to avoid the risk of clogging
    • Filters marked "R" for "Reusable"


Gas mask filter codification

Gas filters

For each gas mask category and depending on the nature of gases or vapors, there are different gas mask filter types. Each respirator cartridge is labeled with a letter and a specific color for every gas or gas family in compliance with the EN 14687 European standard.


Gas mask filter respirator cartridge color codes:


type A AX filter for gas mask


Organic gas and vapor with boiling point above 65°C (solvents, hydrocarbons, alcohols, benzene, ethanol, refrigerants/freons, white spirit)

type A respirator filter


Organic compound gas and vapor with boiling point below 65°C (many VOCs, methyl acetate, acetone, chloroform, methanol, phenol, styrene)

type B filter cartridge for mask


Inorganic gas and vapor (hydrocyanic acid, bromine, chlorine, cyanide, chlorine dioxide, fluorine, hydrogen sulfide, carbon disulfide)

CO type respirator filter


Carbon monoxide

type E gas mask filter


Acid gas and vapor – mainly associated with P3 – (acrylic acid, formic acid, nitric acid, hydrogen chloride, sulfur dioxide, hydrogen fluoride)

Type Hg gas mask filter


Mercury vapor and derivatives - mainly associated with P3

Type K gas mask filter


Ammonia and organic derivatives (DMA, DMEA, hydrazine, methylamine, MMH, UMDS)

Nox gas mask filter


Nitric oxide, nitrogen oxide, nitrous vapor

REACTOR gas mask filter


Radioactive iodine, radioactive methyl iodine

type SX gas mask filter


Specific manufacturer mentioned gas and vapor

type P gas mask filter against particulates and dusts


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)


Find the proper respirator cartridge filter for your application


Gas mask filter categories:

According to the EN143 and EN143/A1 standards, air purifying respirator filters are gathered into efficiency categories.

Maximum toxic substances concentrations allowed:

– Half mask respirator: 50 times the OEL

– Full-face mask respirator: 2000 times the OEL

. Class 1 (lower efficiency): Canister filter (ex: A1) – small capacity, gas rate below 0,1% volume

. Class 2: Cartridge filter (ex: ABEK2) – intermediate capacity, gas rate below 0.5% volume

. Class 3: For a gas rate below 1% volume

Particles filter

For gas mask filters, there are different particles filter classes:

- P1 class filters – low efficiency, stop at least 80% of this aerosol (penetration below 20%)

- P2 class filters – intermediate efficiency, stop at least 94% of this aerosol (penetration below 6%)

- P3 class filters – high efficiency, stop at least 99,95% of this aerosol (penetration below 0,05%)

Combined filters (gas and particles)

As the name implies, a combined gas mask filter stop both gases and particles. These filtering respirator cartridges are heavier than aerosol or gas cartridges but are more efficient. Air enters first a particle filter (which is also a pre-filter) and then goes through a gas filter.

Combined gas and particles filters provide safety against paint droplets and gases as well. These respiratory protective cartridges are mainly used for liquid spraying works.

Filtering air purifying respirator usage limits

Never use filtering respiratory personal protective equipment in the following situations:

- Ambient oxygen rate below 19%

- In confined spaces or any poorly ventilated areas: tanks, tunnels, boat slips…

- When the substance concentration is unknown or immediately dangerous to life or health (IDLH)

- When the substance concentration exceeds the allowable concentration or the filter capacity

In these situations the use of atmosphere supplying respirators like SCBAs, supplied air respirator systems and emergency escape breathing devices is recommended