Fit Testing Protocol
How often must fit testing be performed under WorkSafeBC and CSA Z94.4, and what triggers re-testing?
WorkSafeBC OHSR s.8.40(2.1) requires fit testing before initial use of a tight-fitting respirator, at least once a year, whenever there is a change in respirator facepiece (brand, model, or size), and whenever changes to the user’s physical condition could affect fit (e.g., significant weight change, facial surgery, dental changes, scarring).
What is the difference between a user seal check and a fit test, and how do they interact in the protocol?
A user seal check is a simple functional check performed by the wearer each time the respirator is donned to verify an apparent seal (positive or negative pressure). A fit test is a formal, structured evaluation using a qualitative or quantitative protocol to demonstrate and document that a specific respirator achieves an effective seal. WorkSafeBC requires a user seal check before each use and before proceeding with a fit test.
Which fit testing protocols are acceptable under WorkSafeBC, and are US OSHA CNC protocols recognized?
WorkSafeBC accepts fit tests performed in accordance with CSA Z94.4, which allows qualitative methods (irritant smoke, saccharin, Bitrex) and quantitative methods (ambient aerosol CNC, controlled negative pressure). OSHA’s modified ambient aerosol CNC protocols are US-specific; in BC/Canada, employers may use ambient aerosol CNC devices provided the test procedure aligns with CSA Z94.4 requirements.
A fit testing protocol is a formal, standardized procedure (qualitative or quantitative) used to evaluate and document whether a specific make, model, and size of tight-fitting respirator achieves an effective seal on an individual worker’s face, in accordance with CSA Z94.4 and WorkSafeBC OHS Regulation (BC), and OSHA 29 CFR 1910.134 Appendix A (US). It includes test methods, exercises, performance criteria, frequency, documentation, and preparatory steps.
On a manufacturing or shop floor, a fit testing protocol is implemented via the plant’s Respiratory Protection Program. Core steps include: identifying tasks requiring tight-fitting respirators based on hazard assessments; scheduling initial and annual fit tests; ensuring workers are clean-shaven and have not eaten or smoked before qualitative tests; conducting threshold screening; performing user seal checks; executing fit tests with prescribed exercises (e.g., normal breathing, deep breathing, head movements, talking, bending); documenting results (worker ID, respirator make/model/size, test type, date, result, tester); and integrating with daily operations to verify workers use the same respirator model/size tested. Supervisors track expiration dates and non-conformances via compliance systems.
Facial hair and PPE interference: Workers not clean-shaven where the facepiece seals or wearing different PPE during work than during the fit test, invalidating the seal and violating WorkSafeBC s.8.40 and CSA Z94.4.
Using non-tested respirator models or sizes: Workers are fit tested on one make/model/size but later issued a different respirator due to supply changes, without repeat fit testing, violating WorkSafeBC requirements.
Expired or missing annual fit tests and poor documentation: Fit tests not repeated annually, records missing method, tester, test agent, or respirator details, leading to compliance violations and inspection findings.