Respiratory Protective Equipment Guide

What is RPE?

Anyone working in dusty environments is required to wear respiratory protective equipment (RPE). Even if dust management systems are in place, they don’t always capture every dust particle, so RPE protects the user from airborne dust.

According to the Health and Safety at Work etc Act 19745 and the Management of Health and Safety at Work Regulations 1999, employers have a legal responsibility to control substances hazardous to health in a workplace.

RPE may also be applicable under the Control of Asbestos Regulations 2012, Control of Lead at Work Regulations 2002, Ionising Radiations Regulations 1999, and Confined Spaces Regulations 1997.

Types of RPE

There are generally two types of RPE available for workers. Respirators filter the air being breathed in to remove harmful substances, and breathing apparatus provides a stream of clean air for the worker to breathe in.

• Non-powered Respirators – rely on the user's breathing to draw air through the filter
• Powered Respirators – use a motor to pass air through the filter, offering a clean supply of air
• Breathing Apparatus – requires a separate supply of breathing quality air from an independent source.

Within these broader categories, RPE is designed to protect the worker from hazards, suit various work situations, and match any additional requirements of the worker. This includes the size, gender, and build of an individual.

Breathing apparatus and respirators can be tight-fitting masks, relying on the seal with the user's face (which requires a face fit test). Loose-fitting facepieces are powered respirators or breathing apparatus supplying clean air to the user (such as helmets, visors, or hoods).

The exact RPE used may also have to factor in any underlying respiratory or health issues the wearer has. Respiratory protective equipment must be adequate to reduce exposure to the hazard to a level suitable for the wearer's health and also suitable for the wearer, task, and environment.

Emergency Escape Breathing Apparatus, including 15 Minute Escape Sets and Chemical Escape Sets, are also available in cases where large amounts of harmful substances could be released if there’s a system failure or accident when working with dangerous substances.

RPE Filters

Filters are available for solid or liquid particulates or vapours and gases. It is vital to choose the correct filter for the job.

For this, you need to identify the work hazard during the COSHH risk assessment. Some examples are below, although your line of work may involve additional hazards.

Solid particles:

• asbestos dust
• wood dust
• silica dust
• flour
• stone dust
• smoke
• fungal spores
• welding fumes

Liquid particles:

• sprays, such as paint, pesticides, cleaning liquids
• aerosols
• mists, such as cutting fluids and oil mist

Vapours and gasses:

• solvent vapours
• carbon monoxide
• engine fumes
• sewer gas
• chlorine

Particle filters and gas/vapour filters are available as two different products. Particle filters don’t protect against gasses and vapours, and vice versa. So, your workplace may require various forms of RPE for each worker. Neither filter type can be used in oxygen-deficient atmospheres.

Assigned Protection Factors

Your decision will depend on the amount of hazard in the air and its form. The protection they offer will be determined by several factors, including the protection factor, which is the ratio of hazardous substances outside the RPE to the amount inside the RPE.

Each RPE type and class is categorised by an assigned protection factor (APF). The APF is a number rating indicating how much protection the RPE is capable of providing. For example, if used properly, RPE with an APF of 10 will reduce the wearer’s exposure by at least a factor of 10, so the wearer will only breathe in one-tenth or less of the amount of substance.

Only a few number ratings are used, so RPE APFs will be 4, 10, 20, 40, 200, or 2000. When calculating the protection factor, always choose an APF above the calculated value.

You can work out the ratio using the method below:

When hazardous substances are classed as carcinogens or could potentially cause asthma, exposure needs to be reduced to a level as low as possible.

Quantitative and Qualitative Face Fit Testing

Quantitative face fit testing uses methods such as particle counting to effectively measure the quality of the seal and the effectiveness of keeping out particles. Qualitative face fit testing relies on a person's sense of taste when wearing a hood with and without a mask.

Read our guide on Fit Testing & Respiratory Workplace Protection to find out more.

Why is RPE important?

Respiratory illnesses are often chronic. Health issues may not become apparent until years after exposure to harmful substances, by which time it is too late to act.

Some of these issues can prove fatal. Occupational respiratory diseases can kill tens of thousands of people every year.

So, while RPE should be the final line of defence in the workplace, it can be the only solution in some cases. Therefore, its suitability and quality are imperative.