Since radon detected in indoor air is a serious health concerns, the EPA recommends that you always test the air in the house for radon prior to purchase. A second testing procedure should be performed for radon in the drinking water. If the air in the house tests positive for an alarming level of radon, then you should definitely follow up with a test of the drinking water Radon in the water isn’t a common issue but shouldn’t be ignored. If your source of water comes from a public water system, investigate into whether it comes from a surface (river, lake, or reservoir) or ground water (underground) source. A surface water source usually means that any radon in the water is released into the air before ever reaching the tap. A groundwater source requires contacting the local Water & Sewerage board to find out if they have tested the water for radon. If they haven’t completed readings of the water, you should request that it be done. If they fail to cooperate, there are state & national agencies you can turn to for assistance. If you have a water well on your property, how deep the well is will make a big difference. The well water is probably not contaminated with radon. There is sufficient natural filtering in most cases, because the water seeps through rock, which is a natural filter. The radon is effectively released from the water, making it safe to drink. Surface water well depends on the depth of the well and should be tested for the possible presence of radon. If you have any suspicions that radon might be present in your house or water, completing a test is a simple process.