It is the question every federally regulated employer asks once they understand the new radon limit: do we have to hire a certified professional, or can we do this ourselves?
The answer matters commercially and it is frequently stated too confidently in both directions. Here is what the regulations actually say, who decides, and where the real bar sits — which turns out not to be a certificate.
TL;DR: The Canada Occupational Health and Safety Regulations require the employer to appoint a "qualified person," defined as someone who, because of their knowledge, training and experience, is qualified to perform that specified duty safely and properly. No provision requires C-NRPP certification. But the qualified person must produce a signed written report containing observations and recommendations on compliance and on sampling and testing methods — and that document, not a card, is the actual test of whether your appointment holds up.
What the regulation requires
Section 10.4(1) of the Canada Occupational Health and Safety Regulations provides that where the health or safety of an employee is likely to be endangered by exposure to a hazardous substance in a work place, the employer shall, without delay, "appoint a qualified person to carry out an investigation in that regard," and notify the work place committee or health and safety representative of the proposed investigation and of the name of the qualified person appointed.
"Qualified person" is defined in the regulations:
"qualified person means, in respect of a specified duty, a person who, because of his knowledge, training and experience, is qualified to perform that duty safely and properly."
Three features of that definition do the work.
It is a competence test, not a credential test
The definition names knowledge, training and experience. It does not name any certification, designation, licence or professional body. Nothing in Part X requires a C-NRPP certified professional for radon measurement, and no other federal provision imports one.
It is task-specific
"In respect of a specified duty" is easy to skim past and important. Qualification attaches to the duty, not to the person in general. A building engineer may be a qualified person for ventilation inspection and not for a radon hazard investigation, or the reverse. The question is never "is this person qualified?" but "is this person qualified for this duty?"
The employer appoints — and has to be able to justify it
The regulation places the appointment on the employer. As Canadian OHS guidance consistently frames it, it is not possible to publish a general list of the exact knowledge, training and experience required; every organisation must determine the requirements for the task, and the employer should be able to justify the basis on which a person is considered adequately qualified, suitably trained and sufficiently experienced.
That is the real obligation: not to hold a particular certificate, but to be able to explain your appointment if asked.
Two points employers usually miss
The competence can be held by a team. Canadian OHS guidance is explicit that the abilities making up competence may be held by a single individual or by a group of people. A radon investigation involves protocol design, placement, chain of custody, laboratory interpretation and report writing — there is no requirement that one person hold all of it.
Competence can be built. Organisations can prepare individuals or teams through education, training, skills development and experience, including mentorship, assisting more senior workers, and structured observation. An employer who trains a facilities lead to a documented protocol and keeps a record of that training is doing exactly what the framework contemplates — and the training record is part of how the appointment is justified later.
Where the actual bar sits: the report
This is the part that gets lost in the certification argument, and it is the one that decides whether a self-managed approach is realistic.
Section 10.5 requires that on completion of the investigation, and after consultation with the work place committee or health and safety representative, the qualified person shall set out in a written report signed by the qualified person:
- their observations respecting the criteria considered under s. 10.4(2) — which include the properties of the substance, routes of exposure, acute and chronic health effects, control methods, the concentration employees are likely to be exposed to, and whether levels are likely to exceed 50 per cent of the values in s. 10.19(1) or the levels in s. 10.26; and
- their recommendations respecting the manner of compliance with sections 10.7 to 10.26, including recommendations respecting sampling and testing methods.
That report must be kept for thirty years from the date it was signed.
So the honest test of your appointment is not "does this person have a card?" It is: can this person write that document, sign it, and stand behind it in thirty years' time? For a straightforward single building with a competent facilities lead, a documented protocol and good records, that can be a reasonable yes. For a complex portfolio, a building with variable ventilation, or a situation where the result is likely to be examined, it is often a no — and recognising that is itself good judgement.
What Health Canada says
Health Canada's Guide for Radon Measurements in Public Buildings is the recognised method for workplace measurement. Its position on professional involvement is that a C-NRPP Measurement Professional would ideally be involved in the measurement strategy and implementation.
"Ideally" is doing precise work in that sentence. It is a recommendation about best practice, not a legal condition — and it is worth noting what it recommends professional involvement in: the strategy. Deciding how many detectors go where, in which rooms, over what period, is the part where expertise changes the outcome. Hanging a detector on a shelf is not.
What C-NRPP certification is, and what it is not
The Canadian National Radon Proficiency Program certifies radon professionals against a national standard, and its certifications are referenced by Health Canada. A C-NRPP Measurement Professional has completed training and examination, works to a published quality assurance and quality control manual, and is subject to certification renewal.
Certification is therefore strong, portable evidence of the knowledge, training and experience the regulation asks for. That is a genuine advantage, and it is the simplest way for an employer to satisfy itself — and to demonstrate later — that the appointment was sound.
What it is not is a statutory requirement. When you see s. 10.4 cited alongside a statement that testing must be performed by a certified professional, the section is being characterised rather than quoted. Employers are entitled to know the difference between what the law requires and what a service provider recommends — and then to choose the higher standard if they want to, for their own reasons.
When to engage a certified professional anyway
Independent of what the regulation demands, these are the situations where professional involvement is the sensible call:
- Ventilation that varies between occupied and unoccupied hours. Health Canada's occupied-hours correction involves continuous monitors and a ratio calculation with explicit limits on when it may be used. This is expert work.
- Results above the guideline, where interpretation, mitigation design and verification follow.
- Large or complex portfolios, particularly where a phased approach must be justified to the regulator.
- Anything likely to be contested — litigation, insurance, a real estate transaction, a grievance, or a result an occupant disputes.
- Schools, care facilities and continuously occupied buildings, where the stakes and the interpretation are both higher.
- No internal capacity. If nobody in your organisation can credibly write and sign the s. 10.5 report, appointing them does not make them qualified.
The practical answer
For a single straightforward building where an employer has a competent internal person, a documented protocol, C-NRPP-listed devices, an accredited laboratory and proper records, a self-managed investigation is defensible on the face of the regulation.
For anything with complexity, scale or contested stakes, engage a certified professional — not because the regulation compels it, but because the report is the deliverable and expertise shows up in it.
The mistake to avoid is at either extreme: assuming certification is legally mandatory when it is not, or appointing someone internally who cannot produce the document the regulation requires.
Common questions
Does the law require a C-NRPP certified professional for workplace radon testing?
No. The Canada Occupational Health and Safety Regulations require the employer to appoint a "qualified person," defined by knowledge, training and experience in respect of the specified duty. No provision requires C-NRPP certification. Health Canada's guide states a C-NRPP Measurement Professional would ideally be involved in the measurement strategy.
Can an employee be the qualified person?
Yes. The regulation places the appointment on the employer and does not restrict it to external parties. The employer must be able to justify the appointment on the basis of that person's knowledge, training and experience for that duty, and must notify the work place committee of the investigation and of the appointed person's name.
Can more than one person share the role?
Canadian OHS guidance recognises that the abilities constituting competence may be held by an individual or by a team with different fields of expertise.
How does an employer demonstrate someone is qualified?
Through documented training, relevant experience, a defined protocol, and ultimately the quality of the signed report required by s. 10.5. Training records are part of the picture; the report is the proof.
What if we appoint someone and get it wrong?
The appointment is the employer's decision and the employer's exposure. If there is genuine doubt about internal capacity, that doubt is itself the answer.
Read next
What a compliant radon record contains · How commercial radon testing works · The workplace radon legal brief · Phased compliance for large portfolios
RadonTest.ca provides testing logistics and laboratory submission. We do not perform radon mitigation and we do not interpret health risk — Health Canada is the health authority on radon in Canada. This page describes publicly available regulatory information and is not legal advice; whether a particular appointment satisfies the regulation depends on your circumstances.
Sources
Canada Occupational Health and Safety Regulations (SOR/86-304), s. 1.2 (definition of "qualified person"), ss. 10.4, 10.5, 10.6, 10.19, 10.26, consolidated on the Justice Laws website; Canada Labour Code, Part II; Canadian Centre for Occupational Health and Safety, "Health and Safety Legislation in Canada — Competent"; Health Canada, Guide for Radon Measurements in Public Buildings; Canadian National Radon Proficiency Program; Canada Gazette, Part II, Vol. 160, No. 3 (SOR/2026-10).