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Why Consider Testing Your Home for Radon

You can’t smell it, taste it or see it, but radon gas should not be overlooked.  Radon gas is considered the second leading cause of lung cancer in Canada after smoking.  Because many homes are built on bedrock, there is a chance that radon may be present in those homes.  Fortunately, it is possible to measure the radon gas levels in your home with  a meter in order to assess the risk.  REAL now has a meter for local residents to borrow.

Where is It

Radon gas is a radioactive, colourless and odourless gas emitted when naturally occurring radium breaks down in soil, rock, or water.  Accumulation of this gas is likely to occur in the lower levels of the home, especially in unfinished basements.  If the area is poorly ventilated, radon gas is more likely to accumulate and pose a greater health risk.   But the amount of radon present in homes can vary widely even between neighbouring houses.

Nearly 20% of houses tested in the Leeds, Grenville and Lanark District Health Unit area were shown to have radon levels above 200 Bq/m³ .

Radon can enter a home through

  • cracks or joints in foundation walls and floor slabs
  • dirt floors
  • spaces around pipes and posts, floor drains and sump pump holes
  • ventilation systems
  • window casements
  • cavities inside walls
  • well water

High radon levels are not just a possible situation in older homes. Tight home construction in newer homes may lead to increased radon concentration as air exchange is reduced.  

What to Do if Radon is Detected

Whether you need to take action will depend on the level of radon detected in your home.  Health Canada has set guidelines outlining maximum acceptable levels.

  • Less than 200 becquerels per cubic meter (Bq/m³) – no action required
  • 200-600 becquerels per cubic meter (Bq/m³) – take action to reduce the levels in the next two years
  • Greater than 600 Bq/m³ – take action within the year.

Since there can be a large variation in radon levels in a house, long-term testing is recommended.  So if you discover elevated radon levels, you will probably want to look into long-term testing where the home is testing for  a period of at least 91 days, preferably over the winter months, and sent to a laboratory to be read.

If you determine that radon is a problem you can contact a mitigator who has been certified through the Canadian  National Radon Proficiency Program (C-NRPP).  Actions could include sealing or improving the ventilation of an area, and are not necessarily expensive, but could reach up to $3,000.  REAL can provide the name of a firm in the area you could approach.

Corentium Home Radon Gas Detector

REAL has purchased an AirThings Continuous Corentium Radon Meter for lending.  This is a small, palm-sized digital meter that is simple to use.  The meter uses 3 AAA  batteries (user supplied), and displays readings on an LCD screen.   You should sample your home for at least seven days.  More meter details from manufacturer.  In order to borrow REAL’s meter you must:

  • Sign  a waiver (see the waiver)
  • Provide a $300 cheque to REAL which will be held until the meter’s return
  • Return the meter within two weeks.

To arrange to borrow the meter, please contact:

Katie Hoffman
(613) 983-3360
[email protected]

Please note that at times there may be a waiting list.

Using the Radon Meter 

Corentium User Manual
Suggestions Regarding Meter Placement
Corentium Air Things Website


Health Canada  
Take Action on Radon  
Cross-Canada Survey of Radon Concentrations in Homes 
Health Canada brochure showing radon concentrations across Ontario

Radon: Is it in Your Home – Health Canada
Bob Woods on Radon – April 1, 2019 Presentation in Perth