Radon is a naturally occurring radioactive gas and comes from the natural breakdown (radioactive decay) of uranium. It is usually found in igneous rock and soil, but in some cases, well water may also be a source of radon. The Environmental Protection Agency recommends that testing for radon in homes be conducted on the lowest lived-in level of the home. However, for licensing and renewal purposes, the Office of Children and Family Services will accept tests performed on the lowest level used for day care purposes (but not the kitchen or bathroom). If a provider living in a radon zone has already had his/her home tested for radon and can provide the test results, no re-test is required. Re-testing is not required every licensing period but it is required if a provider has major renovations or construction work completed in his/her home or property, as these actions may alter radon results.