Comprehensive Guide to Choosing Respirator Filters
Understanding the critical role of respirator filters in protecting against hazardous substances is essential for ensuring workplace safety. This guide delves into different types of respirator filters, their applications, and standards, providing you with the knowledge to select the right filter based on your specific needs. FILTER TYPES AND STANDARDS: Respirator filters are categorized based on the protection they offer against different hazards, including particles, gases, and vapors. European standards have set the criteria for these filters:| EN 14387 | Focuses on anti-gas and combined filters |
| EN 143 | Targets particle filters, introducing classifications like P1,P2, and P3 for dust resistance and reusability. |
| EN 372 SX | Specializes in anti-gas filters against specific substance combinations, extending the coverage of EN 14387. |
| EN 149 | Defines specifications for disposable masks, emphasizing single-use protection |
| Aerosol filters are crucial for environments with suspended solid or liquid particles. Their design aims to protect against these particles with negligible falling speeds. | ![]() |
| Class P1 filters (low efficiency) | Stop at least 80% of this aerosol (i.e., penetration of less than 20%) |
| Class P2 filters (medium efficiency) | Stop at least 94% of this aerosol (i.e., penetration of less than 6%) |
| Class P3 filters (high efficiency) | Stop at least 99.95% of this aerosol (i.e., penetration of less than 0.05%) |
| P1 | Annoying dusts, non-toxic fibrogenic dusts |
| P2 | Toxic dust (wood, polyester resin, etc.), metal fumes (welding fumes), Oil Mist |
| P3 | Very toxic dust (asbestos, arsenic, cadmium, etc.) lead, welding fumes, Oil Mist |
| Protection against gases and vapors requires filters designed for specific substances, identifiable by unique markings. |
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| Kind | Color | Area of use |
|---|---|---|
| A | Brown | Organic gases and vapors with a boiling point above 65°C |
| B | Gray | Inorganic gases and vapors (except carbon monoxide CO) (*) (*) some manufacturers offer specific filters against carbon monoxide (CO) |
| E | Yellow | Sulfur dioxide (SO2) and other acidic gases and vapors |
| K | Green | Ammonia and organic amine derivatives |
| HgP3 | Red + white | Mercury vapors |
| NOP3 | Blue + white | Nitrogen oxides |
| AX | Brown | Low boiling point organic compounds (65°C) |
| SX | Purple | Specific compounds designated by the manufacturer |
| Class 1 | The lowest capacity (cake) |
| Class 2 | Average capacity (cartridge) |
| Class 3 | Largest capacity (can) |
| AB1 (also A1B1) (or 2 or 3) | Brown + gray | Mixed filter against organic gases and vapors and class 1 (or 2 or 3) inorganic gases and vapors |
| BK1 (also B1K1) (or 2 or 3) | Gray + green | Mixed filter against inorganic gases and vapors and against ammonia and class 1 (or 2 or 3) organic amine derivatives |
| AE1 (also A1E1) (or 2 or 3) | Brown + yellow | Mixed filter against organic gases and vapors and sulfur dioxide and acid vapors |
| ABEK1 (also A1B1E1K1) (or 2 or 3) | Brown + gray + yellow + green | Mixed filter against organic, inorganic gases and vapors, sulfur dioxide, acids and against ammonia and class 1 (or 2 or 3) amine derivatives |
| AXP1 (or 2 or 3) | Brown + white | Combined filter against low boiling point organic gases and vapors and against class 1 (or 2 or 3) aerosols |
| AB1 (or 2 or 3) (also A1B1 or 2 or 3) P1 (or 2 or 3) | Brown + gray + white | Combined filter against class 1 (or 2 or 3) organic and inorganic gases and vapors and against class 1 (or 2 or 3) aerosols |
| Type A filtration | Protection against organic vapors with a boiling point above 65° C (solvents and hydrocarbons): Acetates, Acids (acetic, acrylic), Acrylate (methyl ethyl), Alcohols, Benzene, Butanol, Butyl Glycol, Cresols, Dichloro (-ethane, – benzene, -toluene), Aromatic essences Ethanol, dichloroethyl, Ethyl glycol, Isopropanol, Kerosene, Methyls, Perchlorethylene, Phenols, (AB), (AK), Styrene, Turpentine, Trichlorethylene, Trichloroethane, Toluene, White spirit , Xylenes |
| AX type filtration | Protection against organic vapors with a boiling point below 65° C: Methyl acetate, Acetone, Bromoethane, Butane, Chloroethane, Chloroform, Vinyl chloride, Dichloroethane, Dichloroethylene, Dichloromethane, Diethylamine, Dimethyl ether, Formate ethyl, Freons, Methanol, Methylbutane, Trichloromethane |
| Type B filtration | Protection against inorganic gases and vapors : Acids (hydrogen cyanide, nitric, hydrogen sulfide), Aminopropane, Bromine, Hydrogen bromide, Chlorine ( ), Cyanides, Chlorine dioxide, Fluorine, Formalin), Arsenic hydrogen, Isocyanates, Nitroglycerin, Sulfide carbon |
| Type E filtration | Protection against: Acids (hydrobromic, hydrochloric, hydrofluoric, formic), Sulfur dioxide, Sulfur dioxide, Hydrochloric gas |
| Type K filtration | Protection against ammonia and certain amine derivatives: Aziridine, Butylamine, Diethylamine, Diisopropylamine, Dimethylamine, Dimethylhydrazine, Ethylamine, Ethylene imine, Hydrazine, Isopropylamine, Methylamine |


