Law, standards and program requirements

Respiratory protection is one of the most heavily regulated areas of personal protective equipment. Both countries require employers to provide approved respirators, to run a written program and to cover fit testing, training and maintenance. The details differ. This lesson sets out the legal framework in your country, the standards it references, the elements every program must contain and the special case of voluntary use.

The legal framework

Each province and territory has its own occupational health and safety act and regulations, and federally regulated workplaces follow the Canada Labour Code. All of them impose a general duty on employers to take every reasonable precaution to protect workers, and most contain specific respirator requirements that reference CSA Z94.4, Selection, use and care of respirators. Approval of the respirators themselves almost always relies on the United States National Institute for Occupational Safety and Health (NIOSH), because Canada does not run its own general respirator approval program.

Two cautions apply across Canada. First, several regulations still name older editions of CSA Z94.4, such as the 1993 or 2002 editions, while the current edition is CSA Z94.4-18 (reaffirmed in 2023). Inspectors generally expect the edition named in your regulation as a minimum, and many employers follow the current edition as good practice. Second, CSA released a revised draft, CSA Z94.4:25, for public review in 2025; it adds a dedicated section on health care settings. At the time of writing, check CSA Group for whether the revised edition has been published and which edition your regulator expects.

What a written program must contain

Although the wording differs, the required program elements are essentially the same in both countries. The table below lists them. Every later lesson in this course expands on one or more of these elements.

CSA Z94.4-18 also emphasizes management responsibilities and clarifies the supervisor's role. Supervisors are expected to make sure workers use the respirators selected for them, to watch for problems with fit, comfort and condition, and to support the program administrator. The 2018 edition added guidance on comfort as a factor in selection and fit testing, on interferences such as facial hair, eyewear and dentures, and on bioaerosol exposures.

Approval of respirators

Canadian regulations generally require respirators approved by NIOSH. A NIOSH approval number, in the form TC-84A-xxxx for particulate respirators, appears on the respirator or its packaging, and the approval covers the complete assembly: the facepiece, the specific filters or cartridges and any other components. Mixing parts from different manufacturers voids the approval. During the COVID-19 pandemic Canada developed CSA Z94.4.1:21, a performance standard for filtering respirators intended to support a Canadian certification program aligned with NIOSH requirements. Respirators certified to it are marked with Canadian classes such as CA-N95. Check whether your regulation accepts them for workplace use.

Voluntary use

Sometimes workers want to wear a respirator even though the hazard assessment shows it is not required, for example an N95 during dusty sweeping well below the limit, or during allergy season. Voluntary use is generally allowed, but the employer still has responsibilities, because a respirator can create hazards of its own, such as a dirty facepiece or a worker with a heart condition wearing a tight-fitting mask in hot conditions.

Canadian rules on voluntary use are less detailed than OSHA's. CSA Z94.4 expects the employer to make sure voluntarily used respirators do not create a hazard, and many employers apply a simplified version of their program: information on limitations, cleaning and storage, and medical screening for tight-fitting elastomeric respirators. If the hazard assessment later shows the respirator is needed, the use is no longer voluntary and all program elements apply.

Responsibilities on multi-employer sites

On construction sites and in contracted maintenance, several employers' workers may share the same atmosphere. Each employer is responsible for its own workers' respiratory protection, but the employer that controls the site, such as the constructor or host employer, must coordinate. A painting contractor's spray mist can expose an electrician working nearby who has no respirator and no idea the exposure exists. Coordination means sharing hazard information, scheduling incompatible work apart, setting up controlled areas with signs, and confirming that each contractor has its own program.

Records

Keep records of hazard assessments and exposure monitoring, respirator selection decisions, medical clearances (with confidential medical details held by the health professional, not the supervisor), fit tests, training, inspections of emergency respirators and breathing air tests. Provincial rules vary on how long records must be kept, and exposure records may be needed decades later for occupational disease claims, so many employers keep them for at least 40 years after employment ends.

Inspections and enforcement

When an inspector visits a workplace where respirators are used, the questions are predictable. Is there a written program, or written measures and procedures as Ontario calls them? Does it name the hazards and the respirators selected for each task, and explain why? Can the employer show medical clearances, current fit tests and training records for each worker on the roster? Are cartridge change schedules written down and followed? Are respirators clean, in good condition and stored properly? Is breathing air tested? Inspectors also talk to workers, and a worker who cannot explain when to change cartridges or how to do a seal check is evidence that training has not worked. Orders typically require the gaps to be fixed by a set date, and stop-work orders are possible where workers are exposed to serious hazards without adequate protection.

Enforcement is not the main reason to run a good program, but inspection questions are a useful self-audit. If you cannot answer one of them quickly with a document or a demonstration, that part of the program probably does not work in practice either.