Radon is a radioactive gas that has no smell, colour or taste. Radon is produced from the natural radioactive decay of uranium, which is found in all rocks and soils. Radon can also be found in water. Radon escapes from the ground into the air, where it decays and produces further radioactive particles.

Radon from soil gas is the main cause of radon problems. Sometimes radon enters the home through well water. In a small number of hones, the building materials can give off radon, too. However, building materials rarely cause radon problems by themselves.

You can either hire a radon tester or purchase a radon test kit from a hardware store and do it yourself. However, the Environmental Protection Agency (EPA) recommends hiring a qualified tester if you are buying or selling your home. A short-term radon testing kit measures radon for 2-90 days for quick results.

Radon is a naturally occurring, colorless, odorless, radioactive gas. It can seep into homes and other buildings. You're at higher risk for developing lung cancer if you breathe in high levels of radon gas over time (over 4pCi/L or 148 Bq/m3). Tests can measure radon in your home. Mitigation effectively lowers radon to acceptable levels.

For most people, the most likely place you're at risk of being exposed to radon is in your home. The U.S. Environment Protection Agency (EPA) estimates that 1 of every 15 American homes has radon levels above the recommended safety level.

People who work in mines or caverns may also be at higher risk, depending on how many hours a day you're exposed to elevated radon levels. If you smoke and are also exposed to radon, it increases your risk even more.

Radon levels are usually in higher in places that are:

•Closer to the ground, such as basements or underground mines

•Near soil that contains more radioactive metal

•Poorly ventilated

•Processing or storing certain products, such as phosphate fertilizers or uranium

•Very tightly sealed

•Very well-insulated

You can also talk to your child's school about radon levels in school buildings and whether they've had testing. And the U.S. federal government has regulations about radon levels in workplaces. If you're concerned about radon levels where you work, talk to the company's safety officer, or contact the Occupational Safety and Health Administration (OSHA).