Choosing the Correct Respiratory Mask and Filter

Posted: 26 May 2025 By Safety Direct

Filtering facepiece respiratory filter mask on a model - Safety Direct

Respiratory protection equipment (RPE) is essential for protecting yourself against airborne contaminants. These portable, air-purifying devices use filtration systems to provide protection, and there are a variety of filtration methods to choose from. Respirators come in powered and non-powered options, feature different face coverings, and are designed to protect against specific hazards. To choose the most suitable mask for your needs, consider factors like task requirements, exposure duration, user comfort, environmental conditions, and risk assessment. Once you understand your specific needs, it’s easier to determine what RPE offers the best protection.

Step 1: Determine the hazards in your environment

Step 2: Choose the level of protection needed

Step 3: Pick the appropriate mask with applicable filter type

Types of Respiratory Protection Masks

A common type of respiratory mask is a filtering facepiece, which was widely used during the COVID-19 pandemic. These masks are typically non-reusable (NR) and focus on particle filtration. The next level of coverage comes from half masks, followed by full masks, with the maximum level of protection provided by hoods and helmets. Most of these mask types are reusable (R) and require replacement filters or cartridges.

3M filtering facepiece, half mask, full mask and helmet

Powered vs. Non-Powered Masks

Respiratory masks can be powered in two ways:

Negative pressure: The user’s breath draws air through the filter or cartridge and is ideal for short-term exposure.
Positive pressure: Electrical power is used either to supply air directly into the mask (Supplied Air Respirator, SAR) or to power a fan that pulls air through the filter or cartridge (Powered Air Purifying Respirator, PAPR). These types are reusable and preferable in higher-risk environments with extended exposure times.

The Best Respirator Filtration Type

Respirators and masks fall into one of three filtration categories based on their range of protection:

Particle Filters: Designed to trap and hold solid or liquid particles such as dust, smoke, mists, or fine sprays. These filters use ratings based on the efficiency of the filter.

Gas and Vapour Filters: Designed to trap hazardous gases like ammonia or chlorine. These filters use both ratings (indicating absorption capacity) and colour codes (indicating the specific gas or vapour they protect against).

Combination Filters: These filters protect against both particles and gases or vapours.

Understanding RPE Colour Codes

To make sure that you are protected against all the contaminants in your environment, filters have colour codes to indicate the gases and vapours or particles they protect against. Many filters will combine ratings and colours to broaden their effectiveness.

For example, an A1P3 R rating is for a combination filter that is:

A1: Protection against organic gases and vapours with boiling points greater than 65°C to a Class 1 level
P3: Protection against particles to a Class 3 level
R: Reusable

This filter would have brown and white colour indicators and is suitable for applications such as painting, construction, agriculture, and road maintenance where there are less hazardous gases and vapours and higher levels of dust and particulates.

RPE Safety Standards

To ensure the maximum protection by your respiratory protection equipment (RPE), manufacturers must adhere to specific EU standards, ensuring consistency and safety. Each filter will indicate the standards it meets so you can be confident of its protection level. Below is a non-exhaustive list of EU standards that RPE filters follow.

It’s important to understand RPE ratings and classifications when selecting the appropriate protection for your environment. The HSA offers a detailed guidebook on respiratory protective equipment, providing additional guidance on the selection, use, and maintenance of RPE. This guide is valuable for employers, employees, and those responsible for health and safety in the workplace.

At Safety Direct, we carry a wide selection of respiratory protection to help you find the best solution for your workplace. Shop our range online or in store, and if you need advice, our sales team can help you choose the best RPE options for your needs.