Respirator filters selection guide - Respirator filters – select correct classification of filters for smoke

Respirator filters selection guide

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Only the combination of protection masks and respiratory filters ensures protection

There are various filter types: particle, gas (e.g. ABEK) or combination filters. Depending on where you will be using them, you can protect yourself against multiple hazardous substances all at the same time.

A colour-coding enables you to instantly recognise the filter type. In addition, filters are classified according to their efficiency or capacity. We will explain this here in greater detail.

Correctly reading and using filter colour codes: Here's how it works

You can only be sure of respiratory protection when you have chosen the right type of filter for the hazardous substance you are dealing with. All respirator filters are labelled with standard colour coding used throughout Europe in accordance with the EN 14387 standard. This enables you to instantly recognise which type of protection each filter provides.

A filter with the green colour code and the label "K" for example, always protects against ammonia and organic ammonia derivatives. Gas filters that cover different gases, or combination filters that provide additional particle protection, thus have several colour codes and a compound label. An example is an ABEK filter with the colour code brown-grey-yellow-green. It protects against gases and vapours of organic and inorganic compounds as well as against sulphur dioxide, hydrogen chloride, ammonia and organic ammonia derivatives.

Slide trough the colour coding for 10 filter types and their application scenarios:

Filters color code AX

Filter type: AX

Gases and vapours from organic compounds, boiling point <65°

For handling aceton.

Filters colorcode A

Filter type: A

Gases and vapours from organic compounds, boiling point >65°

For handling solvent vapours when removing paint or in bonding, painting and varnishing processes (in combination with a particle filter).

Filters color code B

Filter type: B

Inorganic gases and vapours (for example, chlorine, hydrogen sulphide, hydrocyanic acid)

For welding processes (as an ABE P-filter).

Filters color code E

Filter type: E

Sulphur dioxide, hydrogen chloride 

For cleaning processes involving acids (as an ABE P-filter).

Filters color code K

Filter type: K

Ammonia and organic ammonia derivatives 

For handling liquid fertilisers (as an ABEK-filter).

Filters color code CO

Filter type: CO

Carbon monoxide

Used with escape devices to protect against gases during a fire, or for handling hydrogen peroxide (as a CO NO P-filter).

Filters color code Hg

Filter type: Hg

Mercury vapour 

For handling chemicals (as an ABEK Hg P-filter).

Filters colorcode NO

Filter type: NO

Nitrous gases including nitrogen monoxide 

For handling ammonium nitrate or ozone (as NO P-filter).

Filters color code Reactor

Filter type: “Reactor”

Radioactive iodine, including radioactive methyl iodide

Filters color code P

Filter type: P


For grinding, cutting or drilling processes; contact with bacteria or viruses.

What is the meaning of filter classifications: Filter efficiency and capacity

In addition to the colour coding, gas filters are further classified according to their capacity, and particle filters according to their efficiency. There are three classes, ranging from 1 (lowest level of protection) to 3 (highest level).

So, regarding gas filters, the classes describe the maximum permissible concentration of toxic substances a filter can take.

For particle filters, the filter class clearly indicates how efficiently particles are filtered from the ambient air:

P1 / FFP1: 80%

P2 / FFP2: 94%

P3 / FFP3: 99.9%

P = Particle / Particle class

FFP = Filtering Facepiece

There is one special thing about disposable dust masks, also called FFPs. These masks are made entirely of particle-filtering material and therefore don't require a separate filter like reusable masks. Dust masks only provide protection from particles and are designed to be used once only. Grinding, for example, is a job where this type of mask is commonly used.

See Dräger's newest FFP masks.

Respiratory filter portfolio

The following overview shows our respiratory filter portfolio. Our filter series differ in their connector and have to be selected according to the corresponding respirator. All filter series contain particle, gas as well as combined filters.

Respirator filters – bayonet

Bayonet Filter series

These filters have a Dräger-specific bayonet connection and are used in pairs as a twin-filter system. The bayonet filter series can be used with X-plore 3000 half masks or 5500 full face masks.

Respirator filters – Filters Rd40

Rd40 Filter series

Filters with the standard thread connection Rd40 according to EN 148-1 can be used with all half and full-face masks with standard thread connection Rd40, e.g. X-plore 4700 half mask or X-plore 6300 full-face mask.

Respirator filters – Filters Rd90

Rd90 filter series

Rd90 is a Dräger-specific connection to be used in combination with X-plore 4700 half masks.

Knowledge to go

Colour code easy-reference chart
Filters colour codes handbook

Which type of filter is best suited for use during welding processes? Download the colour code chart now for a quick overview of the right filter solutions for any type of task.

Download chart
PDF 42,5KB
Filter classes at a glance
Classification of filters handbook

Filters are classified according to their capacity (gas filter) or their efficiency (particle filters). The particle filter class indicates how efficiently particles are filtered from the ambient air. Our filter class chart gives you a quick overview.

Introduction to light respiratory protection
Introduction to respiratory protection handbook

Will a filtering device provide sufficient protection against hazardous substances? How do you select the right filtering device? Find the answers to these and other important questions in our free handbook.

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Get in touch with Dräger

Draeger Envelop

Draeger Arabia & Co. Ltd

P.O. Box 31787
Al-Khobar 31952 Kingdom of Saudi Arabia 

+966 11 5102636

Not all products, features, or services are for sale in all countries. Please contact your local Dräger representative for more information.