Free radon testing kits are available at all local Luce Mackinac Alger Schoolcraft (LMAS) District Health Departments during January.

Radon, a naturally occurring gas emitted from the earth, can pose a health threat in unsafe concentrations. The health department encourages residents to pick up the free kits to test their homes for radon.

For more information on radon, radon testing, and mitigation, and radon-resistant new construction, call the LMAS District Health Department office in St. Ignace at 643-1100, extension 133.

LMAS District Health Department has provided these frequently asked questions from the Michigan Department of Environmental Quality:

1. What is radon? Where does it come from?

Radon is a naturally occurring radioactive gas that is tasteless, odorless, and colorless. It comes from the breakdown of radium, which comes from the radioactive decay of uranium, both of which are found in at least trace amounts in almost any kind of soil or rock. Granites, shales, phosphates, and certain other types of rock have higher than average concentrations of uranium, and may produce higher concentrations of radon, however, elevated radon levels can occur even in areas with low concentrations of uranium in the soil or rocks.

2. Is radon really a health risk? I've heard it is a scam.

Yes, radon is a Class A carcinogen, which means it is known to cause cancer in humans. It is the second leading cause of lung cancer after smoking, and results in approximately 21,000 lung cancer deaths in the United States each year. Not everyone who breathes radon will develop lung cancer. A person's risk is determined by such things as how much radon is in a home (and/or workplace, school, or other indoor environment); the amount of time a person spent there, and whether a person smokes or have ever smoked. The longer a person is exposed, and the higher the radon level, the greater the risk

3. How do I know if I have a radon problem in my home?

The only way to know whether a home has elevated radon levels is to test the home. There are no physical signs to warn a person of the presence of radon, and it cannot be detected with the senses. And since radon levels can vary significantly from home to home, a neighbor's test results can't be used to determine whether or not a home has a problem. Homes must be tested.

4. How does radon get into my home?

Radon enters homes through openings in the foundation floor or walls, wherever the foundation is in contact with the soil. Because it's a gas, radon can travel through the soil, and it generally moves from an area of higher pressure to one of lower pressure. In most cases, the soil is at higher pressure than the house, and if radon is traveling along the foundation, it can be pushed into the lower pressure area through openings such as sump crocks, crawlspaces, space around plumbing or wiring, floor/wall joints, cracks, hollow block walls, or other entry points. Tiny or large openings in the foundation floor or walls can act as entry points, and the pressure difference between the soil and the house acts as the driving force that allows radon to enter a home.