Radon can be absorbed in the soil by groundwater and spring water. In individual cases, radon dissolved in water can lead to elevated radon concentrations in homes.

Elevated radon concentrations in the air can occur in apartments if the water supply is from the home's own well and the water is piped directly from the source into the house. Particularly when showering, but also when cooking, the radon dissolved in the water can get into the air. In unfavorable cases, this can lead to an increased radon concentration in the room. However, the contribution to the total radon exposure is usually negligible.

The consumption of drinking water also makes some contribution to the radiation dose to humans. In most cases, however, this is negligible due to the usually low radon content of drinking water in Austria. To protect health, the Drinking Water Ordinance stipulates that appropriate remedial measures must be taken if radon concentrations exceed 1,000 becquerels per liter. According to the Austrian Food Code, suitable remedial measures are primarily to refrain from using the water or to mix the water with uncontaminated water.

In operations such as waterworks and radon cure facilities where large quantities of water are reacted, high radon concentrations may occur, making protective measures necessary for the personnel working there.