City
Radon levels in Guelph homes from the 2024 survey, and C-NRPP certified testing and mitigation providers with a business address in Guelph, dated.
Photo: J. S. (Steve) Bond, CC BY-SA 4.0, cropped, via Wikimedia Commons.
13.5
%Share of properties in the Guelph, ON reporting unit with radon at or above 200 Bq/m³ in the 2024 Cross-Canada Radon Survey.
2
Businesses with a business address in Guelph and at least one active C-NRPP credential, as of 2026-10-18. Providers based elsewhere may also serve Guelph.
Survey figures for the Guelph, ON reporting unit
| Measure | Value |
|---|---|
| Properties below 100 Bq/m³ (%) | 60.2 |
| Properties from 100 to 199 Bq/m³ (%) | 26.3 |
| Properties at or above 200 Bq/m³ (%) | 13.5 |
| Geometric mean (Bq/m³) | 72.4 |
| Geometric mean, weighted by building type (Bq/m³) | 83.2 |
| Highest observed (Bq/m³) | 801 |
| Sample | population 165,588 (2021 Census); approximately 600-699 properties with radon data |
2024 Cross-Canada Survey of Radon, Version 1.1 (CCSR.24.1.1), section XII, Table 1, page 43
Sorted alphabetically by business name. Every C-NRPP certified business is listed free, and payment never affects the order.
C-NRPP
Service area
Commercial Measurement and Mitigation: Guelph
Last registry check
C-NRPP
Service area
Residential and Commercial Measurement: Guelph; Guelph; Residential Measurement: Guelph
Last registry check
Grant
Up to $1,500 toward home radon mitigation. Radon is named as eligible. Current. As of 2026-09-01.
Forgivable loan
Varies by service manager, roughly $15,000 to $25,000. Radon is not named. Varies by service manager.. As of 2026-09-18.
Warranty coverage
Up to $50,000 where the Agreement of Purchase and Sale was signed after 1 February 2021, otherwise $15,000. Radon is named as eligible. Current for qualifying homes.. As of 2026-09-18.
Free or subsidized testing
Radon is named as eligible. Current. As of 2026-09-18.
Province or territory
Radon by census division, and every certified provider in Ontario.