Radon is a colorless and odorless radioactive gas. It is produced when small amounts of uranium and radium in soil and rocks decay. Radon gas will also decay into smaller radioactive particles that can be inhaled into the lungs where it can damage cells and cause lung cancer.

Radon is naturally released in low concentrations, but due to lack of ventilation inside your house, gas can become more concentrated. It has been estimated that nearly 1 out of every 15 homes in the US has elevated radon levels.

The Environmental Protection Agency suggests that homes be tested for radon, and should register at a level of 4 picocuries per liter or less. The test should be conducted in the lowest level of the home suitable for occupancy, and you should make sure that the test is done correctly by following the EPA Test Checklist.

There are two types of testing devices available: Passive and Active. Passive Devices (such as charcoal canisters, alpha track detectors, and charcoal liquid scintillation devices) are exposed to air in the home for a specified amount of time, and sent to a laboratory to be analyzed. Active Devices (like continuous radon monitors and continuous working level monitors) continuously measure and record the amount of radon in the air, and require operation by trained testers.

Radon levels can be reduced by increasing the airflow into the house, keeping the vents open year round, and discouraging smoking in the house.