Warning signs before you pay for a radon test, system or monitor: uncertified installers, recalled detectors, false low readings and what to check first.
Photo: Oaktree b, CC BY-SA 3.0, cropped, via Wikimedia Commons.
Voluntary
No province or territory requires radon professionals to be certified. Health Canada's action guide notes that provinces have the power to regulate professions and none has done so for radon, and it recommends hiring C-NRPP certified professionals.
No province or territory requires radon professionals to be certified, so anyone can offer to test your home or install a system. Health Canada recommends a C-NRPP certified professional. It also warns that you may be offered radon work by people who are not qualified. Before you pay, check three things: the certification, the device and the plan. See how to hire and check a radon professional.
A logo on a website does not prove a company is certified. C-NRPP tells you to double-check the certification before you hire, even when its logo is on the company’s site. Ask for the certification number. Then look it up yourself with C-NRPP’s Certification Check. Do this before you sign a contract.
Find a C-NRPP certified professional near you.
Health Canada has recalled or flagged electronic radon monitors that gave inaccurate readings. A recall names specific models and ASINs, not whole brands, so match the exact model number on the device. Check the same model against the C-NRPP performance list before you pay.
Illegal to resell
Health Canada's recall notices state that it is illegal to sell, redistribute or give away a recalled product in Canada. Each recall names a specific model, not a whole brand.
Check the unit on the screen too. Canadian results are in Bq/m³. One of these monitors showed a “Coefficient of injury” instead of a radon unit.
Take care when the person quoting your job also sells the monitor they recommend. That is a conflict of interest worth asking about. It does not prove anything on its own, so check the device against the C-NRPP list before you pay for it.
See which radon test kits and monitors you can trust.
Some recalled monitors reported a low value no matter how much radon was in the home. A low number from one of these monitors tells you nothing about your home’s level. If you are not sure about your monitor, take these steps.
Check every tested device and its recall status.
Ask more than one certified professional for a written estimate, and compare them on the same scope of work. Stop and ask questions if a quote shows any of these signs.
About 13%
Average radon reduction in homes that only sealed entry points, in Health Canada's residential radon mitigation follow-up study. Health Canada does not treat sealing as a stand-alone technique.
Health Canada does not treat sealing as a stand-alone technique, and an air purifier is not among its accepted methods. A very low bid may mean a mistake. It can also mean a contractor who does not understand the job well enough to price or finish it.
The contract should describe the method, how the system will operate and the work included. It should show the certification number, liability insurance and workers’ compensation. Many contractors offer to adjust the system until it reaches a set radon level. Read those conditions, and ask these questions.
Documentation package
What C-NRPP says the national mitigation standard requires a professional to leave with the homeowner: the system labels, manuals for the fan and the U-tube manometer, all radon test data, the fan's estimated energy use, and a recommended inspection and retest schedule.
The installer should show you how to read the manometer. See how a mitigation system works and the tests that follow it.
Radon rises and falls by the hour and the season. Health Canada says short-term measurements should never be used to decide whether a home is over the guideline or needs work. C-NRPP accepts short tests to check a new system and for real estate screening. It says to confirm every short result with a long-term test before you decide to mitigate.
Health Canada says a three-month test is the only accurate way to find a home’s level. It does not recommend testing during a sale. A screening during a sale is not a long-term test of at least 91 days. The 2024 Cross-Canada Radon Survey says its regional results should not be used to decide whether to test a specific home.
See how testing works when a home changes hands.
Run through these four checks before you pay for a test, a system or a monitor. You can check each one yourself.