Protecting Against Invisible

Respiratory Protection Equipment: Protecting against invisible respiratory hazards in the workplace

Some of the most difficult health and safety hazards to guard against are those that are difficult or impossible to see. Substances that can be inhaled such as invisible vapours and minute dust particles can cause serious lifelong illness, or potentially even death. This makes the role of Respiratory Protection Equipment (RPE) in the workplace very important. There are two main options available: respirators that filter harmful substances from the air; and breathing apparatus that provide clean air.



The Control of Substances Hazardous to Health (COSHH) regulations set out requirements to minimise hazards in the workplace. They require employers to: identify and assess the concentration of hazards; provide only CE-approved Personal Protection Equipment; and establish a documented training programme for employees that use RPE to ensure correct use, fitting and maintenance including cleaning, replacement and storage. RPE should only be used where all attempts to remove or reduce the levels of hazard have already been made by installing extraction equipment or using physical barriers, for example.



In general, there are two types of respiratory hazard: particulates such as mists, fumes, dusts or fibres; and gas and vapours such as solvent vapours or acidic gases. It is also necessary to consider the nature of work being undertaken to identify the origin of potential hazards. Process-generated hazards include mists, dusts, fumes or gases that are produced when heating, sanding or cutting materials; and bought-in hazards such as bottled gases, solvents or chemicals. Any product classed as ‘Dangerous for Supply’ comes with a Material Safety Data Sheet (MSDS) or Safety Data Sheet (SDS), which should provide information on health hazards, substances contained in the product, and the type of RPE needed.



There are various types of respirator and breathing apparatus, offering different levels of protection with each type and class of RPE categorised by its Assigned Protection Factor (APF). The APF is a simple rating that indicates how much protection is offered by a device, in percentage terms. For example, as long as RPE is used correctly, an APF of 10 will reduce exposure to the wearer by at least a factor of ten; or put another way, the RPE wearer will breathe in one-tenth or less of the amount of substance present in the air. If multiple hazards are present, such as both dust and gas, it will be necessary to assess the protection factor for each and choose the appropriate RPE based on the highest protection factor required.

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In general, disposable respirators only protect wearers from particulate hazards, but they are cost-effective, versatile, easy to use, require no maintenance, and are hygienic because they are discarded after use. They have different moulded shapes to suit individuals, can be valved or unvalved (valved respirators reduce exhalation effort so are cooler to wear and reduce eyewear misting), and most have adjustable nose clips for increased comfort.



Reusable respirators are available in full and half-mask options (full-face respirators also protect the eyes) to protect the wearer from particulate and/or gas and vapour hazards, depending on the filter type selected. They come in a wide variety of sizes, styles and filter types with hypoallergenic options also available. Reusable respirators are versatile, because their filters can be changed to protect against different hazards.


Air-Fed and Powered

Air-fed and powered respirators provide increased comfort over longer duration with no increase in breathing resistance, and provide increased compatibility, as a number of PPE items are combined into one system, such as head, eye and face protection. They do not require fit testing as they are classed as ‘loose-fitting’. However, they must not be used in conditions that are oxygen deficient or immediately dangerous to life or health.

Air-fed respirators deliver a gentle flow of breathable-quality air supplied by a regulated air compressor via a tube. These devices protect against substances that do not provide a strong warning to workers via smell or taste.

Powered RPE uses a battery-powered fan and motor to draw contaminated air through a filter that captures contaminants and provides clean air to the wearer, and is used to guard against airborne contaminants. It can offer integrated head, eye and face protection, and enable wearers to walk unencumbered by any trailing tubes, but cannot be used to protect against substances with poor warning properties.



It is vital to integrate RPE use into normal workplace activities and provide adequate training for everyone involved in the selection, use, storage and maintenance of RPE so that it operates properly and as specified. In addition, RPE needs to be worn correctly: for example, face-piece-fit testing, required by the COSHH, is a way of checking that a tight-fitting face piece forms an adequate seal. It applies to disposable and reusable respirators and half- and full-face masks, including those that form part of an air-fed or powered respirator. Further information can be found at


Respiratory Equipment Guide

RS offers a wide range of suitable RPE with next-day delivery, competitive-pricing, and bulk discounts, including RS own brand ranges and equipment from the global market leader 3M. RS has also produced a Guide To Buying Respiratory Protective Equipment, which provides advice for equipment managers to consider when selecting RPE. It explains the differences between respirator types and points managers to the equipment required to keep staff safe in the workplace.