Even homes with radon mitigation systems should test for radon every two years

Radon is a naturally occurring radioactive gas that you cannot see, smell, or taste. There are no short-term side effects that could cause alarm or warn of its presence. Long-term exposure to radon increases the risk of developing lung cancer, which accounts for more deaths in both men and women than any other form of cancer in the United States.

Residents who discover elevated radon levels in their homes are advised to install mitigation systems that keep radon levels within recommended levels.

Unfortunately, the installation of a mitigation system doesn’t mean that the work is done.

The Michigan Department of Environment, Great Lakes, and Energy (EGLE) recommends that all people test their home for radon every two years, including those with mitigation systems (active and passive), says Leslie Smith III, EGLE’s indoor radon specialist.

Smith notes that people with mitigation systems sometimes rely on manometers to determine if their mitigation system is keeping radon levels in check.

“The mitigation system manometer does not measure radon concentrations,” said Smith. “The only way to know the radon concentrations in a building is to conduct a radon test.”

Manometers – how they work

A radon mitigation system manometer measures air pressure (indicating flow) within the system piping. These air pressure monitoring devices are found on fan activated radon mitigation systems. A passive radon mitigation system (no fan) does not have a manometer.

When air is moving in the system, the fluid is offset (one side will be higher than the other) and shaped like the letter “J”.

When there is little to no air moving in the system piping, this is primarily due to no electricity, a faulty fan, or a blockage in the pipe (e.g. due to ice, debris, or critter) and is shaped like the letter “U”.

When manometer fluid is at zero on both sides, first check for an electrical issue such as a tripped circuit breaker, or unplugged fan. If no electrical issue is found, then a credentialed radon contractor should be called to evaluate the system.

Get a radon test

EGLE makes radon test kits available to Michiganders through local health department partners. The U.S. Environmental Protection Agency (EPA) recommends installing a radon mitigation system if radon levels are confirmed at or above 4 picocuries per liter.