Radon in workplaces, schools and rental buildings

Who this is for

Employers and building owners. School and daycare operators. Landlords and property managers. Municipalities and anyone who runs a public building with a basement or a slab on grade.

What the rules say in Ontario

Ontario's Occupational Health and Safety Act says an employer must take every precaution reasonable in the circumstances for the protection of a worker. The Ministry of Labour's radon page says that where radon is above 200 Bq/m3, the people in the building should be told it is there and given information on its health effects, and it points employers to private consultants who specialize in radon testing and remediation. Ontario, Radon in the workplace

The 200 Bq/m3 figure is the same Health Canada guideline that applies to homes. Health Canada

How testing works in a building

A measurement professional places detectors by floor and zone, in the rooms people use, for 91 days or more during the heating season. You get a written report with a number for each location, signed by a C-NRPP certified professional. That report is what you show an inspector, a board or a tenant.

How mitigation works in a building

The principle is the same as in a house: lower the pressure under the slab and vent the gas above the roof. A larger building needs more suction points, bigger fans, and sometimes changes to how the ventilation system is balanced. An engineer may be involved. The work takes longer than a one-day home install, and the quote is written after the test report.

Get a building assessment

Send the form below or call. We arrange the test with a certified professional, and the mitigation with a certified installer who does commercial work.