Rosie on the House

A pipe running through a wall serves as an exhaust to remove radon from a house.

You probably know that the main cause of lung cancer is smoking, but the second leading cause is radon, a colorless, odorless, tasteless gas that can kill an estimated 20,000 people a year, according to the American Lung Association.

In Arizona, it’s less common to have serious radon leaks in buildings than in some areas of the country, although it can still happen. The Environmental Protection Agency has classified the nation into three zones based on the potential for radon problems. Zone 1 is the worst, and Zone 3 has the least amount of problems. Arizona is in Zone 2, but has pockets of problems.

Most homes in Arizona – particularly in the Tucson and Phoenix areas – are built on so-called “young” soil that has not been consolidated or cemented into solid rock and therefore may be less likely to contain radon. But homes built on granite-like rocks or limestone that may contain traces of uranium will have more radon problems, according to the Arizona Geologic Survey.

Some key points about radon:

• Radon moves up through the ground into the air above and into houses via cracks and gaps in foundations, walls, flooring and the cavities inside walls.

• Any house can have a problem whether new or old, well-sealed or drafty, and with or without a basement.

• If the house next door has radon, that doesn’t mean your house has the same risk.

• Since radon comes from under the house, it’s typical that radon levels will be highest in the lowest floors of the home.

• The more you open your windows to ventilate your home, the lower the radon levels should be.

The only way to confirm that you do or don’t have serious radon levels in your home is with a test. If that test finds higher concentrations of radon, be assured that every house can be fixed and generally at a relatively low cost.

You can buy short-term charcoal test kits online for about $15. The testing material needs to be placed in the lowest level of your house with all exterior doors and windows closed during testing time, which lasts from three to seven days. Then you mail the device back to a laboratory for analysis.

A staff member from our office ran a test at his home and was notified that his radon result was within safe limits at 1.1 picocuries per liter. (Picocuries is the measurement system used for radon.) The smaller the number, the better. At 4.0, the radon level in a home reaches the “action level,” according to the EPA, and needs to be reduced.

What if you have a high radon reading? Just sealing cracks in slabs or flooring or walls is not enough to make your home safe. Robert Brown of Arizona Foundation Solutions says that lowering the radon level to acceptable limits can cost from about $1,200 to $2,500.

Typically, a 4-inch diameter PVC exhaust pipe is installed in a closet and runs from below your concrete slab up to your attic. An exhaust fan on top of the pipe runs continually to blow away radon. Electricity to run the fan is part of the cost of mitigation; fans need replacing every 10 years or so. A larger than average home might need two exhaust pipes.

To learn more about radon, check out the website of the Arizona Radiation Regulation Agency at .

Next week we’ll talk about decluttering for a fresh start in the New Year.

For more do-it-yourself tips, go to An Arizona home building and remodeling industry expert for 25 years, Rosie Romero is the host of the syndicated Saturday morning Rosie on the House radio program, heard locally from 8 to 11 a.m. on KNST-AM (790) in Tucson and KGVY-AM (1080) and -FM (100.7) in Green Valley. Call 888-767-4348.


Recommended for you

Load comments