Radon in Homes

What is Radon?

Radon is a colorless, odorless radioactive gas found naturally in the environment. It is produced by the natural breakdown of uranium commonly found in soils and rock. When radon is released from the ground into the outdoor air, radon mixes with large volumes of fresh air and is diluted and is not a concern. However, in enclosed spaces, like homes, it can sometimes accumulate to levels that can pose a health risk. The new guideline from Health Canada recommends that the level of radon in the air in a home in a normal living area be no more than 200 Becquerels per cubic metre (Bq/m³) per year.

How does Radon enter my home?

Radon can enter a home through any place it finds an opening where the house contacts the soil: cracks in foundation walls and in floor slabs, construction joints, gaps around service pipes, support posts, window casements, floor drains, sumps or cavities inside walls.

What is the Health Risk?

Radon exposure increases your risk of developing lung cancer. It is the second leading cause of lung cancer after smoking. The risk of lung cancer depends on the level of radon in your house, how long you are exposed and whether you smoke (or are exposed to second-hand tobacco smoke).  Exposure to radon and tobacco smoke together significantly increases your risk of lung cancer.

 (Source: Report of the Radon Working Group on a New Radon Guideline for Canada)

The chart above illustrates that the risk for a non-smoker at 800 Bq/m³ is higher than for all common accidental deaths (motor vehicle accidents, drownings, falls, fire and more) combined. We take precautions against accidental deaths by putting on our seatbelts, wearing lifejackets or ensuring that our smoke detectors are working - we should also be testing our homes for radon!

How can I get my home tested for radon?

There are two ways of getting your home tested for radon.

1. You can purchase a radon detector such as a charcoal canister, electret ion chamber (commercially known as E-PERM) or an alpha-track detector in some retail stores that sell building, hardware or health care products. They are also available online or by mail through companies that specialize in home improvement and radiation safety. You can leave these devices, also known as "passive monitors," in your home for a specific period of time and then send them to a laboratory for analysis. The cost of the test using these simple devices is about $50.

2. You can contract a trained technician or a professional home inspector to test for radon levels in your home, though this may be more expensive. Consult your local Yellow Pages for home inspection services or radon testing services, or contact Health Canada for a list of service providers.

Radon levels may vary daily, weekly, or even seasonally, depending on the climate, indoor ventilation and heating systems used. The best time to measure radon levels in your home is during cold weather (e.g., October to April) when indoor radon levels are generally highest. Health Canada recommends testing for a minimum of three months. Tests for shorter periods can give inaccurate results. Radon levels are usually higher in basements and other areas of the home that are in contact with soil.

Minimizing your risk

If the radon level in your home is above the Canadian guideline of 200 becquerels/metre³, you can easily take steps to reduce the level. The higher the radon level in your home, the sooner it needs to be fixed.

If your home tests above the guideline, here are some ways to reduce the level of radon:

• Increase the ventilation to allow an exchange of air.

• Seal all cracks and openings in foundation walls and floors, and around pipes and drains.

• Renovate existing basement floors, particularly earth floors.

• Install a radon removal system using a fan and piping to draw the radon from under the home         and expel it outside. This is typically done by a contractor and is the most common and effective method of reducing radon levels.

Need more Info

Radon: A guide for Canadian Homes, Canadian Mortgage and Housing Corporation
https://www03.cmhc-schl.gc.ca/catalog/productDetail.cfm?cat=16&itm=36&lang=en&fr=1330513830453

Guide for radon measurements in homes, Health Canada
http://www.hc-sc.gc.ca/ewh-semt/pubs/radiation/radon_homes-maisons/index-eng.php 

Radon testing and monitoring, Radiation Safety Institute of Canada
http://www.radiationsafety.ca/community/home-radon-testing