In Canada, the federal workplace radon exposure limit drops from 800 Bq/m³ to 200 Bq/m³ on January 30, 2027. The change was made by SOR/2026-10, a regulation registered on January 30, 2026 that amends the Canada Occupational Health and Safety Regulations under the Canada Labour Code. It applies to all federally regulated workplaces — about 1.3 million employees, roughly 8% of the Canadian workforce — and it puts the duty squarely on the employer.
Most affected employers have never heard of it. The regulation was published in the Canada Gazette in February 2026 inside a broad hazardous-substances package covering nanomaterials, thermal stress and UV radiation, and it received almost no coverage. This guide explains, in plain language, exactly what the rule says, who it covers, where it came from, and what happens next.
One point worth stating plainly, because it is still widely described incorrectly: this is not a proposal, a plan, or a stated intention. The regulation was made by the Governor in Council, registered on January 30, 2026 (P.C. 2026-49), and published in the Canada Gazette, Part II on February 11, 2026. The consultation stage closed in 2023. What remains is only the coming-into-force date, and that date is fixed by the regulation's own text. Anyone still being told the government "plans to" or "intends to" lower the limit is working from information that is two years out of date.
TL;DR: From January 30, 2027, federally regulated employers in Canada must ensure no employee's radon exposure averages more than 200 Bq/m³ over a year — a fourfold tightening of the previous 800 Bq/m³ limit. The duty belongs to the employer, the metric is an annual average, and the change aligns workplaces with Health Canada's long-standing 200 Bq/m³ guideline for homes. If your organization is a bank, airline, railway, trucking or courier firm, broadcaster, telecom, port, pipeline, Crown corporation, First Nations band council, or part of the federal public administration — this applies to you.
What the regulation actually says
The operative text is one sentence. As amended by SOR/2026-10, subsection 10.26(4) of the Canada Occupational Health and Safety Regulations reads:
"The employer must ensure that no employee, other than a nuclear energy worker as defined in section 2 of the Nuclear Safety and Control Act, is exposed in any year to a concentration of radon that on average, over the year, is higher than 200 Bq/m³."
Two features of that sentence do most of the work. First, the duty sits on the employer — "the employer must ensure." The previous version said no employee "shall be exposed"; the new wording names who is responsible. Second, the limit is an annual average, not a spot reading. An employer cannot know whether an annual average is above or below 200 Bq/m³ without measuring it, which is why the practical effect of this one sentence is a testing obligation. The Government of Canada's own analysis of the regulation says so directly, noting that the new requirements for radon testing and mitigation affect all workplaces covered by the Code where radon is present.
What actually changes for employers
The number is the headline, but the shift in posture matters more.
| Until 30 January 2027 | From 30 January 2027 | |
|---|---|---|
| Limit | 800 Bq/m³ annual average | 200 Bq/m³ annual average |
| Duty holder | "No employee… shall be exposed" | "The employer must ensure that no employee… is exposed" |
| When testing happens | In practice, when a concern was raised or the action level was approached | Testing is how an employer demonstrates it has met an annual-average duty |
| Remediation trigger | Above 800 Bq/m³ | Above 200 Bq/m³ |
| Records | Varied across the five OHS regulations | Harmonized — hazard investigation and air sampling records kept 30 years |
The practical consequence: a building that is legally compliant today at 500 Bq/m³ is non-compliant on 30 January 2027 with nothing about the building having changed. Every federally regulated employer holding a result from the 800 Bq/m³ era needs a new number.
Key dates
| Event | Date | Detail |
|---|---|---|
| Regulation made and registered | January 30, 2026 | SOR/2026-10, Order in Council P.C. 2026-49 |
| Published | February 11, 2026 | Canada Gazette, Part II, Volume 160, Number 3 |
| In force | January 30, 2027 | Section 77(1): "the first anniversary of the day on which they are registered" |
The one-year gap between registration and coming into force was deliberate: stakeholders asked for a transition period to adapt to the new requirements. That transition year is the window in which employers are expected to measure and, where needed, fix — because the limit is an annual average, a meaningful measurement takes months, not days. We walk through the timing arithmetic in detail in our compliance timeline guide.
Who is covered
The Canada Labour Code's occupational health and safety rules apply to federally regulated workplaces. That includes:
- Air, rail, road and marine transportation (airlines, railways, interprovincial trucking and bus lines, ports and shipping)
- Pipelines
- Banks (chartered banks — credit unions are provincial)
- Telecommunications and broadcasting
- Postal services and couriers
- Grain elevators, feed and seed mills
- Crown corporations
- First Nations band councils — hundreds of employers, many operating band offices, schools and community buildings in regions with elevated radon
- Parliament and the federal public administration — departments, agencies and federal workplaces across the country
The same 200 Bq/m³ limit was also added to the Oil and Gas Occupational Safety and Health Regulations for frontier oil and gas operations. Nuclear energy workers are excluded — they are covered by a separate regime under the Canadian Nuclear Safety Commission. And the old radon provision was removed from the on-board-trains regulations, since radon exposure is not an issue on trains themselves (rail yards, stations and offices remain covered under the general rule).
Not sure which side of the line your organization falls on? The distinctions are less obvious than they look — a bank is federal but a credit union isn't; a trucking firm that crosses provincial borders is federal but a local one isn't. We built a dedicated guide: Is my workplace federally regulated?
If your workplace is provincially regulated
About 92% of Canadian workers are covered by provincial or territorial occupational health and safety law, not the Canada Labour Code. SOR/2026-10 does not bind those employers. But radon is not unregulated there either: every provincial and territorial OHS act imposes a general duty on employers to take reasonable precautions against recognized hazards, and radon is a recognized carcinogen with a national guideline of 200 Bq/m³. Ontario, Alberta and several other provinces publish workplace radon guidance, the Canadian Centre for Occupational Health and Safety treats radon as a workplace hazard in its OSH Answers, and Quebec workplaces fall under the CNESST framework. In practice, a provincially regulated employer who knows radon may be elevated and does nothing is exposed under the general duty — without any radon-specific number to point to.
The federal change also sets a benchmark. Regulators, school boards, licensing bodies and courts tend to treat the federal government's own occupational limit as the reference point for what "reasonable" looks like. Provincially regulated employers who measure now are ahead of that shift rather than reacting to it. What applies in each jurisdiction: workplace radon rules by province.
Why 200 — where the number comes from
The old workplace limit of 800 Bq/m³ dated from an earlier era of radon science. In 2007, Health Canada — in consultation with the Federal Provincial Territorial Radiation Protection Committee — lowered its guideline for radon in dwellings from 800 to 200 Bq/m³, based on studies conclusively linking residential radon levels to lung cancer risk. Radon is the second-leading cause of lung cancer in Canada after smoking, and the leading cause among people who have never smoked.
For nearly two decades after that change, an odd gap persisted: the guideline for your home was 200, but the legal limit at your federally regulated workplace remained 800. SOR/2026-10 closes that gap, and brings Canada into line with jurisdictions including Australia, Germany and the United Kingdom, which set workplace radon reference levels at 200 Bq/m³.
How it will be enforced
Occupational health and safety under Part II of the Canada Labour Code is enforced by the Labour Program of Employment and Social Development Canada — not by Health Canada, whose role on radon is scientific guidance and public outreach. The regulatory package that lowered the radon limit also made consequential amendments to the Administrative Monetary Penalties (Canada Labour Code) Regulations, so violations of the amended provisions can attract administrative monetary penalties in addition to the Code's existing compliance and enforcement tools.
How big is the issue?
The Regulatory Impact Analysis Statement published with the proposed regulations estimated that in the first year after implementation, 23,253 workplaces would undergo radon testing — falling to around 90 buildings annually thereafter, as only new buildings would require testing. Of those, roughly 814 worksites were expected to exceed 200 Bq/m³ and require mitigation in the first year (about 875 over twenty years), with approximately 31,529 employees considered at risk. The analysis estimated the radon provision would prevent 9.93 cases of lung cancer over twenty years, at a first-year cost of roughly $15.4 million.
The testing figure is the one worth noting. The mitigation number describes buildings expected to need fixing — but identifying which buildings those are requires measurement across more than twenty thousand workplaces, and that is the work of the transition year. (All figures are the government's own estimates from the proposal stage, on a 2023 baseline.)
Quick answers
Does this apply to my business?
If your organization is federally regulated — banking, interprovincial transport, telecom, broadcasting, postal and courier, pipelines, grain handling, a Crown corporation, a First Nations band council, or the federal public administration — yes. If you are provincially regulated, this specific limit does not apply to you, though radon remains a recognized workplace hazard under provincial law. See our coverage guide.
Is there a deadline to test?
The regulation contains no test-by date. It contains an employer duty that takes effect January 30, 2027, defined as an annual average — and the recognized way to establish an annual average is a long-term test of at least 91 days, ideally during the heating season. The practical consequence: measurement started in fall 2026 produces evidence in hand when the duty begins. The timeline math, explained.
What kind of test counts?
Workplace measurement follows Health Canada's Guide for Radon Measurements in Public Buildings — a different protocol from residential testing. It calls for long-term measurement (a minimum of three months, during the heating season) in every occupied ground-contact room, with one detector per 200 m² in larger rooms and quality-control duplicates on top. The guide states plainly that short-term measurements are not acceptable for deciding whether remediation is needed. Detector counts, placement rules and the full protocol: see our workplace FAQ.
Does this apply to provincially regulated workplaces, schools or daycares?
Not directly — provinces regulate those workplaces. But every provincial occupational health and safety act contains a general duty to protect workers from recognized hazards, and Health Canada's 200 Bq/m³ guideline applies to all indoor spaces. See our guides on radon in schools and daycares and Quebec workplaces under CNESST.
Where is the official text?
The full regulation is published in the Canada Gazette, Part II, Volume 160, Number 3 (February 11, 2026), as SOR/2026-10, and the amended Canada Occupational Health and Safety Regulations are consolidated on the Justice Laws website.
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.
Statute-by-statute detail, with the operative wording and enforcement mechanics: the workplace radon legal brief.
How many Canadian workers this actually reaches: the research on occupational radon exposure.
Read next
Which rules apply to your workplace · The compliance timeline · The legal brief · What a compliant record contains
Sources
Canada Gazette, Part II, Vol. 160, No. 3 — Regulations Amending Certain Regulations Made Under the Canada Labour Code (SOR/2026-10), including the Regulatory Impact Analysis Statement; Employment and Social Development Canada, Introducing amendments to regulations under Part II of the Canada Labour Code; Canada Occupational Health and Safety Regulations, s. 10.26(4) as amended; Health Canada, Canadian radon guideline; Health Canada, Guide for Radon Measurements in Public Buildings; Canadian Centre for Occupational Health and Safety, Radon in Buildings.
Last reviewed against the Canada Gazette text. If you spot an error in our reading of the regulation, tell us — we correct fast and credit the correction.