Most employers preparing for the new federal workplace radon limit expect the deliverable to be a laboratory certificate with a number on it. It isn't. Under the Canada Occupational Health and Safety Regulations, what an inspector, an auditor or a plaintiff's lawyer will eventually ask for is a set of documents, and the laboratory result is one item in it.
This page sets out what that set contains, drawn from the operative provisions rather than from general advice.
TL;DR: A compliant radon file is five things, not one: the hazardous substance record; the qualified person's signed written report; the employer's written control procedure, kept current and available to employees; the test records themselves; and the employee education and training records. Most of it is created before and after the measurement, not by the laboratory.
Why the laboratory certificate isn't the record
A laboratory does one thing: it analyses a detector and reports a concentration. It does not know where the detector was placed, when it was placed and retrieved, what method was followed, who placed it, what the investigation concluded, or what the employer did next. Every one of those is part of what the regulations require, and every one of them is generated in the field or in the office — not in the lab.
This is the single most common misunderstanding in the market, and it is an expensive one, because the missing pieces cannot be reconstructed accurately two years later.
1. The hazardous substance record
Section 10.3 requires every employer to keep a record of hazardous substances used, produced, handled or stored for use in the work place. It may be kept at the work place or centrally for several work places.
The consolidated text currently in force reads: "Every employer shall keep a record of all hazardous substances that are used, produced, handled or stored for use in the work place." SOR/2026-10 replaces that section, and the replacement extends the record to substances used, produced or handled in the work place by the employer, employees or contractors. That extension is easy to miss, and it means the register is not limited to substances the employer itself introduces. Because the amendments are not in force until 30 January 2027, the consolidated regulation on the Justice Laws website still shows the earlier wording — check the Gazette text for the amended version.
2. The qualified person's signed written report
This is the document almost nobody discusses, and it carries the most weight.
Section 10.4(1) requires that where the health or safety of an employee is likely to be endangered by exposure to a hazardous substance, the employer shall without delay (a) appoint a qualified person to carry out an investigation, and (b) notify the work place committee or health and safety representative of the proposed investigation and of the name of the qualified person appointed, so they can participate. The name is part of the notice, not an afterthought.
Section 10.5 then says what must come out of that investigation. On its completion, 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":
- the qualified person's observations respecting the criteria considered under s. 10.4(2); and
- the qualified person's recommendations respecting the manner of compliance with sections 10.7 to 10.26, including recommendations respecting sampling and testing methods.
Two things follow. First, the report is signed — it is a personal professional document, not an anonymous corporate output. Second, the range "sections 10.7 to 10.26" includes section 10.26, which is where the radon exposure limit sits. The qualified person's report is therefore the instrument through which radon compliance recommendations, and the sampling and testing method itself, are formally documented.
The 50 per cent criterion — a threshold almost nobody mentions
Section 10.4(2) lists the criteria the qualified person must take into consideration in that investigation. Paragraph (h) is the one relevant here: whether "the concentration of an airborne chemical agent or the level of ionizing or non-ionizing radiation is likely to exceed 50 per cent of the values referred to in subsection 10.19(1) or the levels referred to in subsections 10.26(3) and (4)."
Radon sits in subsection 10.26(4). Once the limit becomes 200 Bq/m³, 50 per cent of it is 100 Bq/m³ — and whether a building is likely to exceed that figure is a matter the qualified person is directed to consider. This is not a second exposure limit and it does not require action on its own. But it does mean the regulation itself contemplates attention well below the number everyone is planning around, which is worth knowing before treating a result of 150 as the end of the matter.
3. The employer's written control procedure
Section 10.5 does not stop at the report. Paragraph (b) requires that the employer "establish and keep up-to-date written procedure for the controlling of the concentration or level of the hazardous substance in the work place and make it readily available for examination by employees," in a form determined in consultation with the policy committee or, failing that, the work place committee or health and safety representative.
Three obligations in one sentence, and each is testable: the procedure must be written, it must be kept up to date, and it must be available to employees. A radon file that contains results but no control procedure is incomplete on the face of the regulation.
Retention: thirty years, and this is not new. Section 10.6 provides that a report referred to in section 10.5 "shall be kept by the employer for a period of thirty years after the date on which the qualified person signed the report." That obligation is in the regulation today — it does not arrive with the 2026 amendments. Any employer that has ever conducted a hazard investigation under Part X already owes a thirty-year retention on the resulting report.
4. The test records
Where air sampling is carried out, the regulations set out what a test record must contain. Section 10.19(5) — the provision governing records of air sampling tests — requires that a record include:
| Required content | Who generates it |
|---|---|
| (a) the date, time and location of the test | Field, at placement and retrieval |
| (b) the hazardous substance in respect of which the test was made | Field / plan |
| (c) the sampling and testing method used | Plan — and per s. 10.5(a)(ii), recommended by the qualified person |
| (d) the result obtained | Laboratory |
| (e) the name and occupation of the person who made the test | Field |
Four of the five come from you, not the lab. That is the whole point.
A note on scope, because precision matters here: section 10.19 addresses airborne chemical agents, while radon is dealt with under section 10.26 as ionizing radiation. The five-element list above is the content standard the regulations set for air sampling test records, and it is the template the industry works to for radon measurements. Employers should treat it as the minimum a radon test record should contain rather than assume it is optional.
The record must be kept at the employer's place of business nearest the work place where the sample was taken. On retention, section 10.19(4) currently specifies three years for air sampling test records — a much shorter period than the thirty years already applying to the qualified person's report under s. 10.6. The SOR/2026-10 package harmonises hazard investigation and air sampling record retention across the federal OHS regulations at 30 years, closing that gap. Build the file to the longer horizon.
5. Employee education and training records
This is where the "worker notification" obligation actually lives, and it is more specific than most summaries suggest.
Section 10.14 requires every employer, in consultation with the policy committee or work place committee or health and safety representative, to develop and implement an employee education and training programme on hazard prevention and control. For each employee who is or is likely to be exposed to a hazardous substance, that programme must cover, among other things, "all hazard information of which the employer is aware or ought to be aware" and — explicitly — "the observations referred to in subparagraph 10.5(a)(i)".
In plain terms: the qualified person's observations from the hazard investigation must be taught to affected employees. The investigation is not an internal document.
The programme must be reviewed and, if necessary, revised at least once a year, whenever conditions change in respect of hazardous substances in the work place, and whenever new hazard information becomes available. Section 10.15 requires a paper or electronic record of the training given to each employee, readily available for their examination, kept for two years after the employee ceases to be exposed.
The file, assembled
| Document | Provision | Created by |
|---|---|---|
| Hazardous substance record (incl. contractors) | s. 10.3 | Employer |
| Appointment of a qualified person; committee participation | s. 10.4(1) | Employer |
| Notice to committee of the investigation and the name of the qualified person | s. 10.4(1)(b) | Employer |
| Signed written report: observations + compliance and method recommendations | s. 10.5(a) | Qualified person, after committee consultation |
| Retention of that report — 30 years from signature | s. 10.6 | Employer |
| Written control procedure, current, available to employees | s. 10.5(b) | Employer, in consultation |
| Test records: date/time/location, substance, method, result, person | s. 10.19(5) standard | Field + laboratory |
| Education and training programme and records | ss. 10.14, 10.15 | Employer, in consultation |
| Warnings at access points where applicable | s. 10.13 | Employer |
What this means in practice
The committee is not optional. Consultation with the policy committee, work place committee or health and safety representative appears at four separate points: the investigation, the report, the control procedure, and the training programme. An employer who tests quietly and files the result has skipped most of the regulation.
Most of the file is created before and after the measurement. The investigation and the appointment come first; the report, procedure and training come after. The three months of detector exposure in the middle is the passive part.
Field data cannot be reconstructed. Which detector was in which room, when it went in, who placed it — capture it at the time or lose it. This is the single most common failure, and it is invisible until someone asks.
Build to 30 years. Radon-attributable lung cancer presents decades after exposure. Whoever opens this file will not be the person who created it, and may not be at your organisation. Write it so a stranger can follow it.
Common questions
Is a laboratory report enough to show compliance?
No. The lab supplies the result — one of the five required elements of a test record, and one document within a larger set that also includes the qualified person's signed report, the written control procedure, and training records.
Who signs the report?
The qualified person appointed under s. 10.4(1). The report must be signed by them and must set out their observations and their recommendations on the manner of compliance, including sampling and testing methods.
Does the health and safety committee have to be involved?
Yes, at several points: the employer must provide for committee participation in the investigation, the qualified person's report follows consultation with the committee or representative, the form in which the control procedure is made available is determined in consultation, and the education and training programme is developed and reviewed in consultation.
How long do we keep it?
The qualified person's report under s. 10.5 must be kept thirty years from the date it was signed — that is s. 10.6, and it is already in force. Air sampling test records are currently kept three years under s. 10.19(4); the 2026 amendments harmonise retention across the federal OHS regulations at 30 years. Training records are kept two years after an employee ceases to be exposed. Build to the longest applicable period.
Do we need a C-NRPP certified professional to sign the report?
The regulation requires a "qualified person" — defined by knowledge, training and experience. It does not require a specific certification. C-NRPP certification is strong evidence of competence and the sensible choice for complex buildings; it is not a statutory condition. See does a certified professional have to do the testing?
Read next
The workplace radon legal brief · How commercial radon testing works · The compliance timeline · Guide for workers and committees
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.
Sources
Canada Occupational Health and Safety Regulations (SOR/86-304), Part X: ss. 10.3, 10.4, 10.5, 10.13, 10.14, 10.15, 10.19, 10.26, consolidated on the Justice Laws website; Canada Gazette, Part II, Vol. 160, No. 3 (SOR/2026-10) and accompanying Regulatory Impact Analysis Statement; Employment and Social Development Canada, Introducing amendments to regulations under Part II of the Canada Labour Code; Health Canada, Guide for Radon Measurements in Public Buildings.