Radon is found in most existing homes.
By Francie Healy
When a couple in Lanark decided to use a radon tester to check their recently-purchased home for radon gas, they were astonished – and concerned – about the levels.
The reading told them their home was showing 25,000 becquerels per cubic metre. Becquerels are a unit of measurement for radioactivity, often written as Bqm3.
Health Canada says that people exposed to radon levels in excess of 200 Bqm3 over long periods of time have a higher risk of developing cancer.
Their exposure was astronomically above safe levels and could have meant an increased lifetime risk of illness.
Radon is an invisible, odourless, naturally-occurring gas found in soil. It seeps into homes through cracks in floors, walls and foundations. It’s found in most homes in varying degrees. When it can’t escape through air leaks or open windows, it can be dangerous, even fatal.
The radon expert well known in Ottawa and surrounding areas is Rob Mahoney of Radon Works, so the couple called him right away.
Four days later, their radon levels were down to 20 Bqm3 from 25,000 Bqm3. Naturally, they were amazed, happy, and relieved.
It’s the kind of story Rob hears all the time.
“It’s not usually that high,” he says. “It doesn’t matter what the levels are, though. The same system does the trick no matter what.”
He explains that most of the time radon levels will be higher in winter, because radon gas is pressure driven. Things like exhaust fans and the heat running create a negative pressure in the basement that draws the gas in from the ground. Climate plays a role, too, because barometric pressure also elevates radon levels.
Rob tells clients that radon systems are not always necessary, because some homes are built to be so well sealed that a radon system isn’t needed. Drafty old farmhouses don’t require a radon system either because the gas has so many places where it can escape. But for modern existing homes, radon levels can get in and get trapped.
Rob began his career with Health Canada, specializing in HVAC systems in labs and operating rooms and developing Radon Mitigation Standards. He is a founding member of the Canadian Association of Radon Scientists and Technologists, certified under the Canadian National Radon Proficiency Program, and the first in the industry to guarantee levels below 100 Bqm3.
Ottawa Renovates has been a source of information about radon with our series of stories, and we hear from people who have taken action because of them.
Francie Healy is editor and art director of Ottawa Renovates.