Last reviewed 31 July 2015

Although personal protective equipment (PPE) should only be used as a last resort, it still plays an important role in protecting employees, particularly when using chemicals. Gordon Tranter looks at one aspect of the use of PPE for work with chemicals; the use of respiratory protective equipment (RPE).

Respiratory protective equipment

RPE can generally be classified within two types.

  1. Respirators that rely on filtering harmful substances in the form of dust, mist, gas or fume from the workplace air.

  2. Breathing apparatus (BA), which gives an independent supply of breathable air, for example, fresh-air hose, compressed airline and self-contained BA; BA is used in toxic atmospheres or if there is a chance of an oxygen deficiency in the work area.

Both types are available with a range of face-pieces: masks, hoods, helmets, visors and blouses. Masks are tight fitting face-pieces. Hoods, helmets, visors and blouses are loose fitting face-pieces.

Legal requirements

Surprisingly, the Personal Protective Equipment at Work Regulations 1992, with the exception of regulation 5: Compatibility of Personal Protective Equipment, do not apply where any of the following regulations apply:

All four of these sets of regulations require a risk assessment to be carried out to identify which harmful substances are present, how workers can be harmed, and how to prevent exposure. All of these Regulations require that RPE should only be used in addition to all other control measures if the combination of these measures fails to achieve adequate control of exposure. The justification for using RPE should be clear in the risk assessment. Under the Confined Spaces Regulations 1997, RPE should be a last resort except in instances where it is used for rescue work.

It is a legal requirement that RPE used at work must be:

  • adequate and provide the wearer with effective protection

  • suitable for the intended use

  • “CE”-marked

  • selected, used and maintained by properly trained people

  • correctly maintained, examined and tested

  • correctly stored.

Under the Reporting of Injuries, Diseases and Dangerous Occurrences Regulations 2013, the malfunction of BA should be reported where the malfunction causes a significant risk of personal injury to the user; or if, during testing immediately prior to use, the malfunction would have caused a significant risk to the health and safety of the user had it occurred during use.

CE marking

Any RPE used must comply with the requirements of the Personal Protective Equipment Regulations 2002 and be CE marked. Equipment must meet the basic health and safety requirements of the EC Personal Protective Equipment Directive (89/686/EEC) to be entitled to carry the CE mark. Manufacturers tend to use Harmonised European Standards for Personal Protective Equipment as the preferred means of demonstrating equipment conformity with the BHSRs.

Employers should not take CE marking as indicating that an RPE device is automatically adequate and suitable for their application. Employers have the responsibility of selecting the correct RPE to meet their specific requirements. They should also be aware that cheap PPE, with counterfeit CE compliance certificates, is on the market and will offer only limited protection.


When selecting RPE, three things should be considered.

  1. The harmful substance(s).

  2. The task and the environment in which it is carried out.

  3. The persons likely to be affected.

Assigned protection factors

The selection process should identify the RPE needed to reduce exposure to the level required to protect the wearer’s health. Each RPE type and class is categorised by an assigned protection factor (APF). The APF is a number rating that indicates how much protection that RPE is capable of providing. APFs can be either: 4, 10, 20, 40, 200 or 2000. Each number indicates the extent to which the RPE will reduce the wearer’s exposure. For example, an RPE with an APF of 10 will, if properly worn, reduce the exposure by a factor of 10.

Suppliers of hazardous substances or mixtures that are used in the workplace are required to provide a safety data sheet (SDS). This should contain information on health hazards, the forms of the substances contained in the product, and the type of RPE necessary to work with it. If the substance has a workplace exposure limit, the APF can be calculated by dividing the quantity of the substance in the air by the exposure limit. Guidance on the type of RPE that should be used for certain work activities — such as cutting or heating certain materials — which may generate airborne harmful substances is available in the Health and Safety Executive’s COSHH Essentials: Easy Steps to Control Health Risks from Chemicals from Chemicals e-tool.

If none of the above methods provide the type of RPE needed it will be necessary to calculate the protection factor. The Scottish Centre for Healthy Working Lives has worked in conjunction with the Health and Safety Executive to develop an online tool to assist in the selection of RPE.

Detailed guidance on the selection of RPE is given in HSG53: Respiratory Protective Equipment at Work: A Practical Guide.

Special cases

COSHH includes special requirements for hazardous substances classed as carcinogens or mutagens, or those that are a potential cause of occupational asthma, for which the exposure has to be reduced to as low a level as is reasonably practicable.

When in an airborne state, biological agents and micro-organisms can be classed as particles, and can usually be removed by filter-type RPE. However, HSG53 recommends the use of equipment fitted with the highest efficiency filter possible (APF of at least 20) to control exposure down to the lowest levels.

When selecting RPE for radioactive materials, the RPE should be capable of giving adequate protection not only from radioactivity but also from any other risks to health, such as those covered by COSHH.

If there is a likelihood of the atmosphere being deficient in oxygen or, if the concentration of a substance in the air could be life threatening, specialist BA will be required.

The task and the environment

The RPE must be selected so that the wearer can work freely and not be put at risk while carrying out the required task in the circumstances in which the work is carried out. This should take into account conditions, such as strenuous activities, which place a physiological burden on an employee. Where clean air is supplied to a facial mask through hoses or by compressed air cylinders the limitation of freedom of movement must be taken into account.

The person

The RPE must be right for the wearer and enable them to work with as little encumbrance as possible. It must be of the right size and correctly fit the wearer. Tight-fitting face-pieces should match the wearer’s facial features and seal adequately to their face. To ensure this, fit testing should be conducted by a competent person; fit testing ensures that the equipment selected is suitable for the wearer. If RPE is used frequently, repeat fit testing should be carried out on a regular basis. (Details on how to carry out a fit test is given in HSG53).

Hair, spectacles or other PPE can break the seal on tight-fitting face-pieces, exposing the user to the risk of breathing in hazardous substances. Workers who have beards or are unable to be clean-shaven should not use a tight-fitting device and an appropriate loose-fitting device should be chosen. COSHH and the Personal Protective Equipment at Work Regulations 1992 require that other PPE worn is compatible with the RPE and does not interfere with the protection offered by the RPE. One way to achieve this is to use combination products, for example, a powered respirator with a head top which incorporates hearing, eye, head and respiratory protection.

Maintenance and storage

Employers who provide any RPE for use at work must take all reasonable steps to ensure that it is:

  • properly used

  • maintained in an efficient state

  • in efficient working order

  • in good repair

  • in a clear condition.

Storage facilities for the RPE should be provided so that it can protect the PPE from contamination, loss or damage — for instance, from harmful substances, damp or sunlight — when not in use.

Thorough examinations and tests

Thorough examinations should be carried out at suitable intervals and suitable records kept of the examinations and tests and of any repairs carried out as a result of these examinations and tests. The examinations and tests of RPE should be carried out in accordance with the manufacturer’s instructions.

Examinations should comprise a thorough visual examination of all parts of the respirator or breathing apparatus to ensure that all parts are present, correctly fitted, and the equipment is in good working order. For breathing apparatus, the quality of the air supplied should be tested. The examinations and tests of items of RPE should be made at suitable intervals dependent on how often the RPE is used and the nature of the risks to health.


COSHH, CLAW and CAR all require records of the examination of RPE to be kept available for at least five years from the date on which it was made. IRR requires these records to be kept for at least two years from the date on which the examination was made.


RPE users should be informed, instructed and trained on the following.

  • Why they need RPE — the results of the risk assessment.

  • Which RPE they need and how to check they have the correct kind.

  • When to wear the RPE.

  • How to wear it correctly.

  • When and how to change filters and other consumable parts.

  • Why fit testing is required (if relevant).

  • How to maintain the RPE in good condition.

  • How to store the RPE when not in use.

  • When to replace RPE.

  • To stop work and leave the area if they think their RPE is not working properly.

  • Reporting defects in the RPE.

  • The procedures to be followed in an emergency.

Training should not be a one-off exercise. It should be reviewed and updated whenever significant changes are made to the type of work or to the substances used, and following a review of the assessment.

All relevant information should be made available to employees or their representatives in accordance with the Health and Safety (Consultation with Employees) Regulations 1996, and the Safety Representatives and Safety Committees Regulations 1977.

The last choice for protection

It should be remembered that RPE should be the last choice for protection. It can only protect the wearer whereas control measures such as automation, enclosure or extraction of hazardous substances can protect everyone working in the area. Furthermore, it is intrusive and uncomfortable to wear. It can give a sense of false protection, especially when not worn in accordance with the manufacturer’s instruction. In some circumstances, it may interfere with communication and vision. Workers with beards or stubble can have considerably difficulty in ensuring an adequate seal of the RPE with their face. In some cases, simple common sense control measures can be significantly cheaper than RPE.


  • HSG53: Respiratory Protective Equipment at Work: A Practical Guide (2013) HSE, available from the HSE website

  • COSHH Essentials: Easy Steps to Control Health Risks from Chemicals (e-tool) HSE, accessible on the HSE website

  • Respiratory Health in the Workplace: Stoneworkers (January 2012) (DVD), HSE

  • Respiratory Health in the Workplace: Welding (January 2012) (DVD), HSE

  • Respiratory Health in the Workplace: Motor Vehicle Repair (January 2012) (DVD), HSE

  • RPE Selector Tool. Scottish Centre for Healthy Working Lives. Accessible through the Healthy Working Lives website