Studies undertaken over the past decade however, have not substantiated this claim. Radon levels have not been found to be higher in well insulated homes. Thus concern about radon should not prevent anyone from taking steps to making living quarters more energy efficient. While most radon literature focuses upon the airborne variety of radon derived directly from soils and rock, it should he noted that ground water may be contaminated also, thus posing a threat for those whose water comes from wells. Radon is not a hazard in city water because it is removed naturally from the water while it is in the reservoir or holding tank.
Some estimates indicate that roughly half a million homes have wells with unsafe levels.
It should be noted that widespread, systematic testing has not been carried out, so it is simply not possible to give firm statistics on the extent of contamination. Detection Testing is the only way to determine radon concentrations in air or water. Usually, if the kit has been approved, this will be indicated on the package. If you are unsure, you may obtain an updated list of companies meeting EPA standards by writing to EPA Office of Radiation Programs, Washington, D.C. 20460. The advantage of the seven-day kit is that it is usually considered to measure a more representative sample of the air where the test is being conducted.