Radon is a colourless, odourless, naturally occurring gas coming from the soil. It can enter buildings through cracks and unsealed openings in:
- basements; and
- foundations.
Radon does not pose an immediate health risk. It becomes a concern only after long-term exposure to high concentrations over many years.
Radon is measured in becquerels per cubic metre (Bq/m3). According to Health Canada’s Guide for Radon Measurements in Public Buildings, recommended levels of radon concentration for acceptable indoor air quality are as follows:
- below 200 Bq/m3 – acceptable
- between 200 Bq/m3 and 600 Bq/m3 – remediate within two years
- above 600 Bq/m3 – remediate within 1 year
We are continuing radon testing in Yukon schools. In 2025–26, we are testing for radon in new school builds and for some schools where mitigation occurred. Some schools will also be re-tested.
Already mitigated
Schools that previously recorded radon levels slightly above Health Canada’s recommended level:
- Christ the King Elementary;
- Eliza Van Bibber; and
- Holy Family Elementary.
Mitigation work was completed and re-testing for radon confirmed levels were reduced to acceptable ranges.
New schools
New school facilities that are being tested:
- Centre scolaire secondaire communautaire Paul-Émile Mercier (CSSC Mercier)
- Dámbü Tän Kets'ádań Kų̀ – Cliff Trail Elementary
- F.H. Collins Secondary School’s modular classrooms
- Hidden Valley Elementary School’s modular classroom
- Robert Service School’s modular classrooms
Schools being re-tested
Re-testing is taking place at:
- Nelnah Bessie John School;
- Ross River School; and
- Teen Parent Centre.
All remaining schools
All remaining schools will be tested in the 2026–27 school year.
Routine future testing
Beginning in 2026, all Yukon schools will be tested at least once every 5 years to ensure radon levels remain within Health Canada guidelines.
In the spring of 2018, radon testing was conducted in Yukon schools. Testing equipment was installed:
- for at least three months; and
- in every single room, on the lowest level of each school, that was used for more than four hours a day.
For each school in the table below:
- Highest refers to the highest radon level recorded in any tested room.
- Lowest refers to the lowest radon level recorded in any tested room.
Health Canada recommends mitigation when radon levels exceed 200 Bq/m3.
| School | Highest | Lowest |
| J.V. Clark | 126 | 56 |
| Jack Hulland | 107 | 30 |
| Johnson Elementary | 107 | 52 |
| Khàtìnas.àxh | 122 | 44 |
| Kluane Lake | 92 | 67 |
| Nelnah Bessie John | 74 | 33 |
| Porter Creek | 67 | 26 |
| Robert Service | 74 | 33 |
| Ross River | 152 | 74 |
| Selkirk | 100 | 37 |
| St. Elias Community | 111 | 59 |
| Takhini | 81 | 30 |
| Tantalus | 85 | 44 |
| Teen Parent Centre | 230* | 230* |
| Vanier | 163 | 26 |
| Watson Lake | 74 | 41 |
| Whitehorse Elementary | 96 | 30 |
| Wood Street Centre | 141 | 41 |
*Note: After this test result, a radon extraction system was installed at the Teen Parent Centre to mitigate radon levels.
If you have questions about radon testing in Yukon schools, email [email protected].