Fit testing of respiratory protective equipment

Introduction

Respiratory protective equipment (RPE) is a type of personal protective equipment (PPE) that is designed to protect the wearer from inhaling harmful airborne contaminants.

RPE can provide protection from the following airborne contaminants:

• dusts
• fibres
• mists
• fumes
• vapours
• gases
• smoke
• biological hazards such as bacteria and viruses.

The hierarchy of control should be used when deciding on measures to control the risk of airborne contaminants. The hierarchy of control is a step-by-step approach to eliminating or reducing risks. It ranks risk controls from the highest level of protection and reliability through to the lowest and least reliable protection.

Where there is a risk of exposure to hazardous substances, including lead, employers must follow the hierarchy of control set out in the Occupational Health and Safety Regulations 2017.

Reducing the risk from airborne contaminates using PPE (including RPE) is the lowest level of control in the hierarchy. The use of PPE is only appropriate:

• as a last resort when there are no other practical control measures available
• as a short-term measure until introducing a more effective way of controlling the risk
• in combination with other control measures to increase their effectiveness.

Where RPE is used as a control measure, it is essential that the selected RPE is:

• appropriate for the contaminant
• the right size and fit
• correctly worn
• appropriately cleaned, maintained and stored.

This guidance is applicable to all industries. Additional guidance is available that explains the use of RPE in specific industries.

Types of respiratory protective equipment

Air-purifying respirators

Air-purifying respirators protect the wearer by filtering contaminants from inhaled air. There are two types of air-purifying respirators:

• Negative pressure respirators require a tight-fitting seal between the respirator and face and rely on the negative pressure created by the face seal to draw air through the respirator filters to remove airborne contaminants. Negative pressure respirators include half-face disposable, half-face reusable and full-face reusable respirators.
• Powered Air Purifying Respirators (PAPRs) provide filtered air to the wearer. They use a battery-powered fan to draw air across the filters and into the respirator creating a positive pressure. PAPRs can have loose-fitting or tight-fitting headpieces including a hood, helmet, or tight-fitting facepiece.

Supplied-air respirators

Supplied-air respirators, also called airline respirators, protect users by supplying clean air directly to the wearer by an airline hose connected to an air compressor. This type of RPE is used for oxygen-deficient atmospheres or work environments where air-purifying respirators would be inadequate.

Self-contained breathing apparatus (SCBA)

A self-contained breathing apparatus (SCBA) is a portable respirator that supplies oxygen, air or other gas from a source that is carried by the user. SCBAs provide a high level of protection in environments that are immediately dangerous to life or health (IDLH), oxygen deficient, or contain unknown airborne contaminants.

Respiratory protection program

Employers that require their employees and contractors to wear RPE should have a respiratory protection program (RPP) in place for the workplace. An RPP outlines procedures and elements that ensure that appropriate RPE is selected, used and maintained. Employers must consult with employees, contractors and any health and safety representatives (HSRs) about measures taken to control risk such as the RPP. A good RPP will have the following elements:

• Appointment of a program administrator.
• Selection of appropriate RPE.
• Medical evaluation for use of RPE.
• Training in the correct use and maintenance of RPE.
• Issue of RPE.
• RPE fit testing and fit checks.
• An outline of where and when RPE is required to be worn.
• Inspection, cleaning, maintenance, and storage of RPE.
• Disposal of RPE.
• Record keeping.
• Program evaluation.

Respirator fit testing

RPE comes in a variety of different shapes, styles, and sizes. One size doesn’t fit all. It is important that employees and contractors are individually fit tested for the particular model and size of RPE provided. If RPE is being used as a risk control, fit testing is needed. Fit testing helps to verify that correctly worn RPE will reduce the risk from airborne contaminants.

A respirator fit test is needed before wearing tight-fitting RPE for the first time. Re-testing should also be done regularly. An annual re-test is recommended. Re-testing is also needed if the wearer’s face changes. For example, due to weight loss or surgery.

Respirator fit testing is the only way to check that a tight-fitting respirator matches the wearer’s facial features and seals adequately to the wearer’s face. Fit testing checks if any air leaks through the seal between the respirator and the wearer's face.

Employers should ensure that respirator fit testing occurs for the following types of tight-fitting RPE:

• half-face disposable respirators
• half-face reusable respirators
• full-face reusable respirators
• tight-fitting PAPRs.

There are two types of fit test methods: quantitative and qualitative.

Quantitative fit testing methods use specialised equipment to measure the seal between the wearer’s face and the respirator.

During the testing, the wearer performs movements such as talking and turning their head. At the end of the test, the machine provides a score known as the fit factor. The higher the fit factor, the better the respirator fits.

Qualitative fit testing is a pass/fail method. It relies on the wearer sensing a bitter or sweet test agent to determine if there is leakage. This method may not be reliable for all employees and contractors as it relies on an individual’s sense of taste or smell. A false pass result means the respirator will not provide the expected level of protection. If the test subject cannot detect the test agent (ie. prior to wearing the RPE being tested), a quantitative fit test should be conducted. This fit testing method is only suitable for negative pressure respirators.

Quantitative fit testing is the preferred method as it provides a precise, objective and repeatable measurement.

There are a number of respirator fit testing validated protocols that outline in detail how to perform quantitative and qualitative fit testing including:

• ISO 16975-3, INDG-479 (UK)
• OSHA 1910.134 (US)
• ANSI Z.88.10 (US)

While the OSHA document is most frequently used, alternative methods can be used if the fit tester is competent in using that method, ie has appropriate training, practical experience and knowledge of the method’s limitations.

If an adequate seal cannot be achieved during the fit test the employee or contractor should be re-tested with different types, shapes and brands of tight-fitting RPE.

If an adequate seal still cannot be achieved, the employee or contractor should be provided with RPE that does not rely on a seal between the face and the respirator such as a PAPR with a loose-fitting hood or helmet-style with a shroud.

Who can conduct a respirator fit test?

Respirator fit testing needs to be conducted by a person with knowledge and experience in RPE fit testing such as:

• a Resp-fit accredited fit tester
• a trained internal staff member (trained by a Resp-fit accredited fit tester)
• a manufacturer or supplier of RPE with adequate knowledge
• an external occupational hygienist/consultant.

The fit tester should provide the employer and employee or contractor with a written record that includes the following details:

• type of test performed
• make, model, style, and size of the respirator tested
• date and time of the test
• result of the fit test.

Respirator fit check

The purpose of a fit check is to ensure that the respirator is positioned correctly on the wearer’s face and that there is an adequate seal between the face and the respirator.

Each time a tight-fitting respirator is worn, the wearer needs to carry out a fit check.

Respirator fit checks can only be performed on negative pressure respirators.

How to carry out a fit check

• Cover or block the filter cartridges with non-permeable material or the palm of your hand if it is big enough.
• Gently inhale and hold for approximately 10 seconds.
• Check if the facepiece has slightly collapsed.
• If the facepiece stays collapsed, there are no air leaks between the face and the respirator. 
• If you find leaks, readjust the respirator to ensure a correct fit. 

If a fit check fails, the wearer should readjust the respirator by repositioning the straps and mask. Repeat the fit check.

If the fit check continues to fail:

• inspect and evaluate the respirator for damage
• try another respirator
• if issues persist, the employer should consult with the supplier and consider a fit test.

Impact of facial hair on respirator performance

Facial hair prevents tight-fitting RPE forming a good seal between the respirator and the wearer's face.

Any facial hair will affect the seal between the respirator and the wearer’s face including:

• stubble
• beard
• moustache that extends to where the respirator sits on the wearer’s face
• sideburns.

Employers need to ensure workers who are required to wear tight-fitting respirators during work are clean-shaven or have no facial hair in the area where the respirator seals to the face.

What if an employee or contractor can’t shave?

If an employee or contractor cannot shave due to medical, religious, or cultural reasons, employers still need to ensure that the employee or contractor is adequately protected from respiratory hazards. Employers should:

• conduct a risk assessment to determine the specific level of risk for the employee or contractor
• consult with the employee or contractor
• consider providing alternative RPE (eg. PAPR with a loose-fitting hood).

Training

Employers must provide employees and contractors with information, instruction, training or supervision as is necessary for employees and contractors to work safely and without risks to health.

Where RPE is used to control risks associated with airborne contaminants, employers should ensure that employees and contractors:

• understand when and why RPE is required
• understand the limitations of RPE and that other measures may also need to be used to control the risks
• can select and use the correct RPE for the relevant tasks and hazards
• understand the importance of conducting a fit check each time a tight-fitting respirator is worn
• know how to fit check and wear RPE correctly
• can maintain, clean, and store RPE in line with workplace procedures.

Legal duties

Employers

Under the Occupational Health and Safety Act 2004, employers must, so far as is reasonably practicable, provide and maintain for employees and contractors a working environment that is safe and without risks to health.

Where a risk to health associated with potential exposure to airborne contaminants is identified at a workplace, employers must eliminate the risk so far as is reasonably practicable. Where it is not possible to eliminate the risk, it must be controlled so far as is reasonably practicable.

Employers have a duty to consult with employees, contractors and any HSRs, so far as is reasonably practicable, on matters related to health or safety that directly affect, or are likely to directly affect them. This includes consultation while identifying hazards or risks in the workplace (including exposure to airborne contaminants) and when making decisions about how to control those risks.

The consultation should be conducted in accordance with any agreed consultation procedures.

Employees

Employees must:

• take reasonable care of the health and safety of themselves and others in the workplace
• cooperate with any action their employer takes to comply with OHS laws
• not interfere with or misuse anything provided at the workplace for health and safety purposes.

These duties mean that employees need to wear and deal with RPE as instructed, not misuse it and report issues such as damage or poor fit to their employer.