Regional variation of seasonal correction factors for indoor radon levels

Radon levels measured for any duration less than one year are subject to seasonal variation. Such radon measurements must therefore be adjusted using an appropriate seasonal correction factor in order to estimate an annual average radon level. Radon mapping has shown that radon concentrations vary between regions within a country but there has been little work examining regional variation in the seasonality of radon levels. This paper investigates this regional variation in indoor radon seasonality in Ireland. Mean regional seasonal correction factors are estimated through Fourier decomposition and we find that there is significant regional variation in the computed seasonal correction factors. We conclude that the use of one national set of mean seasonal correction factors may not be appropriate in all countries.

► This paper investigates the regional variation of the seasonal behaviour displayed by indoor radon levels.
► Fourier decomposition was used to estimate mean regional seasonal correction factors in Ireland.
► These factors were compared to the national set of factors.
► Significant differences between regional and national factors were examined and discussed.