Health Canada's Guide for Radon Measurements in Public Buildings names them in its own title: workplaces, schools, day cares, hospitals, care facilities and correctional centres. These are buildings where people are present for long hours, often continuously, and frequently without the ability to leave — which changes the radon risk calculation in a way no other building type shares.
Yet almost no Canadian guidance is written for the people who run them. This page covers what the protocol requires, why occupancy patterns matter here more than anywhere else, and where responsibility sits.
TL;DR: Health Canada treats these buildings as "dwellings" for testing purposes because of high occupancy of long duration. Most are provincially regulated, so no radon-specific limit applies — but staff are workers owed a general duty, and occupants in care and custodial settings cannot self-protect. The protocol is a detector in every occupied ground-contact room, three months minimum during the heating season. Federal correctional institutions are federally regulated workplaces and will be covered by the 200 Bq/m³ limit from January 30, 2027.
Why Health Canada groups these buildings together
The guide's scope covers buildings "with high occupancy of long duration by the public" and treats them as dwellings for the purposes of radon testing. The logic is exposure arithmetic: radon risk is a function of concentration multiplied by time. A person who works eight hours in an office is exposed for a third of a day. A long-term care resident, a hospital inpatient, or an inmate may be in the same building continuously.
Three factors compound in these settings:
- Duration. Continuous or near-continuous occupancy, sometimes over years.
- Vulnerability. Populations with existing respiratory or health conditions, for whom additional carcinogen exposure carries different weight.
- No ability to leave. In care and custodial settings, occupants cannot choose to reduce their own exposure. Responsibility rests entirely with the operator.
Which rules apply
Provincial facilities — hospitals, long-term care homes, provincial correctional centres, community care facilities — are provincially regulated. No province sets a radon-specific exposure limit. What applies is the general duty in provincial occupational health and safety law (owed to staff), licensing and standards frameworks for care facilities, and Health Canada's 200 Bq/m³ guideline as the recognized benchmark for all indoor spaces.
Federal correctional institutions are federal workplaces. From January 30, 2027, the employer must ensure no employee is exposed to an annual average above 200 Bq/m³ under the amended Canada Occupational Health and Safety Regulations. See SOR/2026-10 explained.
Care facilities in British Columbia operate under the Community Care and Assisted Living Act, where a medical health officer may attach terms and conditions to a licence — the power Interior Health used in 2017 to order radon testing in childcare facilities in its region.
Jurisdiction detail: which rules apply to your workplace and workplace radon rules by province.
The measurement protocol
Identical to other public buildings, and not the residential protocol:
- Every occupied room in ground contact gets a detector — patient and resident rooms, nursing stations, offices, treatment and activity rooms, staff areas. An occupied room is one where a person spends more than four hours a day.
- One detector per 200 m² in rooms larger than 200 m² — wards, dining halls, gymnasiums, large day rooms.
- If the ground-contact level has no occupied rooms, test every occupied room on the first occupied level above, until the footprint is covered.
- Minimum three months, during the heating season. Short-term measurements are not acceptable for deciding whether remediation is needed.
- Quality control — duplicate detectors at 10% of locations, plus blanks.
- Placement — 0.5–2 m from the floor, at least 30 cm from an exterior wall, 10 cm clear of objects, away from HVAC air currents and heat. Excluded: bathrooms, kitchens, storage areas, indoor parking levels.
Detector counts by building type: commercial radon testing in Canada.
The ventilation question — and why it is different here
In offices and schools, ventilation typically reduces or stops outside operating hours, so a long-term detector may report a higher average than what daytime occupants actually breathe. Health Canada's guide provides a method for estimating occupied-hours exposure in those buildings using a short-term continuous monitor.
That correction generally does not apply in hospitals, care facilities or correctional centres, because occupancy is continuous. There are no unoccupied hours to correct for. The 24-hour long-term average is what occupants actually experience, which makes the measurement more straightforward and the result more directly meaningful.
The exception is staff-only areas on a shift pattern — administrative wings, plant rooms — where the standard occupied-hours considerations may apply.
Practical constraints these buildings face
Detector security. Health Canada's guide notes that placement location is constrained by the need for devices not to be disturbed or readily accessible to occupants. In correctional and some care settings this is a serious operational consideration, not a formality — ceiling suspension and high mounting are usually the practical answers, within the placement rules.
Continuous operation. These buildings cannot be closed for testing, and do not need to be — long-term measurement requires no change to occupant behaviour once detectors are placed.
Scale. A hospital may have hundreds of qualifying ground-contact rooms. Detector counts of that size need planning and a documented placement record rather than an ad hoc approach.
Records. For federal facilities, hazardous-substance records must be retained 30 years. For provincial facilities, accreditation bodies and licensing frameworks generally expect environmental testing records to be retained and producible.
What the record has to contain
For institutional buildings the record matters as much as the measurement, and the regulations specify its content: the date, time and location of the test; the substance tested for; the sampling and testing method; the result; and the name and occupation of the person who made the test. A laboratory certificate supplies only the result — the rest is field information captured at placement and retrieval, and retained 30 years.
Note also who may perform the work: the regulation requires a qualified person, defined by knowledge, training and experience, not a specific certification. C-NRPP certification is strong evidence of that competence and the sensible choice in complex institutional buildings with mixed occupancy and mechanical ventilation — but it is not a statutory condition, and the distinction matters when deciding what is required as against what is recommended.
If a result exceeds 200 Bq/m³
Health Canada recommends remedial action within two years for results between 200 and 600 Bq/m³, and within one year above 600 Bq/m³, carried out by certified mitigation professionals, followed by retesting to confirm the reduction. Outside mitigation, there is no fixed retest interval: retest when the building is renovated, when HVAC or airflow changes, or when occupancy or room use changes — all of which are common in institutional settings undergoing continual refit. In complex institutional buildings, mitigation design has to account for existing mechanical ventilation and pressure relationships, which is a reason to involve a certified professional at the design stage rather than after.
For facilities teams: radon, HVAC and ventilation.
Common questions
Are hospitals required to test for radon in Canada?
No province requires it. Federal facilities become subject to the 200 Bq/m³ workplace limit on January 30, 2027. Health Canada's public-buildings guide covers hospitals explicitly and recommends testing.
Do long-term care homes need to test?
There is no radon-specific requirement in any province. Staff are workers owed a general duty, residents are continuously present and cannot self-protect, and Health Canada's guideline applies to all indoor spaces.
Are correctional centres covered?
Federal institutions are federally regulated workplaces and will be covered by the 200 Bq/m³ limit from January 30, 2027. Provincial correctional centres fall under provincial OHS regimes.
Does continuous occupancy change the testing method?
Not the method, but it does simplify interpretation: the occupied-hours correction Health Canada provides for buildings with scheduled ventilation generally does not apply where occupancy is continuous.
How many detectors does a hospital need?
Every occupied ground-contact room, one per 200 m² in larger rooms, plus roughly 10% duplicates and 5% blanks for quality control. For large institutional buildings this is typically dozens to hundreds of detectors.
Read next
How commercial radon testing works · The workplace radon legal brief · Schools and daycares · Workplace radon FAQ
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, nor clinical or facility-accreditation advice.
Sources
Health Canada, Guide for Radon Measurements in Public Buildings (Workplaces, Schools, Day Cares, Hospitals, Care Facilities, Correctional Centres), H129-120/2022E; Health Canada, Canadian radon guideline; Canada Gazette, Part II, Vol. 160, No. 3 (SOR/2026-10); Community Care and Assisted Living Act, S.B.C. 2002, c. 75; CCOHS, Radon in Buildings.