The effect of domestic air treatment equipment on the concentration of radon daughters in a sealed room.

Reports tests of the effect of various air treatment devices on the radon daughter concentrations within a room. Test were carried out using an electrostatic precipitator, a humidifier and a dehumidifier. The ventilation rate of the room was measured using Krypton 85 as a tracer gas.< Finds that the use of a humidifier, dehumidifier or carbon filter gave no significant alteration to the radon concentrations in the room, but that the electrostatic precipitator reduced the concentration considerably and was equally effective when operated with or without the carbon filter. Concludes use of an electrostatic precipitator can reduce the dose to the bronchial epithelium by an order of magnitude and effectively counter the effects even of extremely low ventilation rates.