Fit testing for tight-fitting respirators

The purpose of this safety alert is to highlight the importance of fit testing for tight-fitting respirators for workers who need to use them, and to reinforce this requirement under the Work Health and Safety Regulation 2011.


Tight-fitting respirators (often referred to as masks) rely on having a good seal with the wearer’s face. These are available as both non-powered and powered respirators and breathing apparatus (BA) with either a half mask or a full-face mask. Their performance, irrespective of whether they are non-powered (negative pressure), powered or constant-flow airline BA relies heavily on the quality of fit of the respirator to the wearer’s face. Section 44 of the Work Health and Safety Regulation 2011 places obligations on a person conducting a business or undertaking PCBU to ensure personal protective equipment (PPE) (including respirators) is a suitable size, fit and reasonably comfortable for the worker who is to use or wear it.

Contributing factors

People’s faces vary significantly in shape and size so it is unlikely that one particular model or size of respirator will fit everyone. Inadequate fit will significantly reduce the protection provided to the wearer and can result in immediate and/or long-term health effects.

Fit testing (using a validated protocol) is required to ensure tight-fitting respirators are a suitable fit. It involves checking that a specific model and size of tight-fitting respirator matches the wearer’s facial features and seals adequately to the wearer’s face and is an essential step in the respirator selection process. It will also help to identify unsuitable respirators (which should not be used).

Tight-fitting powered or constant-flow airline BA respirators under positive pressure still require fit testing as studies have shown that during heavy exertion, inward leakage is possible. Powered or constant-flow airline BA respirators which incorporate loose-fitting hoods or helmets do not require fit testing.

Workers must pass a respirator fit test before they first start wearing a tight-fitting respirator. It is not necessary to undertake a fit-test when you are simply replacing a respirator with the exact same make and model you have already been successfully fit-tested to (this goes for both disposable and reusable respirators).