TEMPORAL VARIATIONS OF RADON LEVELS IN DWELLINGS

Several factors determine the concentration of radon in a dwelling: th e uranium content and permeability of the building ground; the constru ction and integrity of the floor; the habits and preferences of the oc cupants. Whereas the geological factors are unlikely to alter over tim e, it is quite possible for structural changes to occur, such as settl ement cracking, which increases radon ingress, and for the occupants t o change their living habits, such as increasing ventilation, which ma y reduce radon levels. New occupants may arrive with entirely differen t lifestyles. Questions arise about the variability of indoor radon le vels as time progresses and as occupants change. The database of radon results for UK homes, which extends backwards for about a decade, is examined for repeat measurements, and the data are analysed so as to a ssess the stability or otherwise of the levels under changing circumst ances.