How do I hire a radon mitigation professional and check they are C-NRPP certified?

Health Canada recommends that all radon measurement and mitigation professionals be certified through C-NRPP. No province or territory requires it, so check the certification yourself before you hire. Our directory lists every business with an active C-NRPP credential, and every one is listed free. Start with the companies there, then work through the checks on this page. Find every certified business near you, listed free.

Hire a C-NRPP Mitigation Professional, not only a Measurement Professional

To have a system designed and installed, hire a company with C-NRPP’s Radon Mitigation Professional certification. A company with measurement certification only is not certified to design or install a mitigation system. C-NRPP certifies four streams:

1. Radon Measurement Professional: places and collects detectors, and reports results from a certified lab.
2. Radon Mitigation Professional: reads results, then designs and installs systems that lower radon, with insurance and a mentorship.
3. CRNCH Installer/Inspector: radon rough-in systems in new homes, included with mitigation certification.
4. Analytical Laboratory: analyzes the detection devices.

Certification of radon professionals

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.

Date

2026-09-18

Sample

Not applicable

Source

Health Canada, Radon action guide for provinces and territories: reduction actions

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See what each certification takes.

Check the certification on the C-NRPP list before you sign

Ask for the certification number and look it up in C-NRPP’s Certification Check before you hire. Do this even if the company’s website shows the C-NRPP logo. Confirm that the name matches, the certification is current, and it covers mitigation, not measurement only.

Certification renewal

20

credits every 2 years

Continuing education C-NRPP requires to renew a certification every two years, with at least 4 credits from C-NRPP approved courses and hands-on work counting for at most 10. Holders also pay yearly fees, take the mandatory renewal course and sign the Code of Ethics, and mitigation professionals must carry insurance.

Date

2026-09-18

Sample

Not applicable

Source

C-NRPP, Professional Resources

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Have a long-term test result in hand before you ask for any quote. Health Canada bases its guideline on the yearly average, and recommends a test of at least three months to estimate it. See how to run the long-term test before any quote.

If the Certification Check shows the certification has lapsed, ask the company about it. C-NRPP certification is valid across Canada, so also ask whether the company works where you live. C-NRPP’s Find a Professional tool searches by location. See the warning signs before you pay.

Ask for proof of certification and insurance, and a written plan

Ask each company the same questions before you hire. Keep their answers, and get the final plan in writing.

1. Ask whether they inspected your home before the estimate.
2. Ask whether they reviewed the quality of your original test.
3. Ask whether they will run diagnostic tests to choose and place the system.
4. Ask whether they will fit a warning device that shows if the system stops.
5. Ask whether they will guarantee a set maximum level, and on what terms.
6. Get a written contract with the method, the work, the total cost, timing and warranty.
7. Check that the contract shows their certification number, liability insurance and workers’ compensation.
8. Ask what warranty covers the work and what covers the fan.

Mitigation documentation

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.

Date

2025-03-01

Sample

Not applicable

Source

C-NRPP, Technical Bulletin: Leave Behind Information (March 2025)

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The national standard requires the professional to leave this package with you when the work is done. Before you hire, ask whether they will leave it. Keep it with the system. See what the label and documentation should show.

Get more than one written estimate, and treat a low quote as a question

Health Canada suggests getting more than one estimate where possible. Ask each company for a written estimate, so you can set them side by side. Compare bids on the same scope of work, so each price covers the same job.

A very low bid may mean a mistake, or a contractor who does not understand the job. Ask the low bidder to walk you through the work their price covers. See what a system costs and what the contract should cover.

The installer should not run the follow-up test

Health Canada says the follow-up long-term test should not be done by the company that installed the system. This avoids a conflict of interest. Plan two tests after the system goes in.

The first is a short-term check, once the fan has run for at least 24 hours. The second is a long-term test in the next heating season. Arrange that long-term test with someone other than the installer. See the tests that confirm a system works.