Variation in long-term radon and daughters concentration with position inside a room

Bare plastic detectors (LR-115 and CR-39) were used in similar conditions to record α-particles from radon and its daughters in more than one hundred houses in the U.K. It was found that LR-115 is more convenient than CR-39 because of its energy discriminating properties. Variation in the long-term radon and daughter concentration ir air was observed in houses by placing bare nuclear track detectors of both types at different positions in the same room. Variation in the concentration of tracer gases at different positions in a room has also been observed through ventilation measurements using gas chromatographic techniques. The significance of these variations for exposure assessment is discussed. (author)