Spatial and temporal variations of radon and radon daughter concentrations within limestone caves

This thesis outlines results from an investigation of radon and radon daughter
concentrations in limestone caves, from a geographical and geological perspective
Investigations were conducted at all geographical scales, ranging from a national
investigation in the four major caving regions of England and Wales to a detailed survey
within a single cave in the Peak District.

The measured radon concentrations in some limestone caves in England and Wales are
amongst the highest ever recorded in the world Significant spatial and temporal
variations were recorded m concentrations at all scales, within a single cave, between
caves in the same region and between different regions Additionally, seasonal and
diurnal variations in concentrations were highlighted. External climatic variables and the
cave radon budget were demonstrated to account for variations in cave radon
concentrations

Within limestone caves seven primary sources of radon were identified and the relative
importance of each to the overall radon budget was determined Sediments and the
contaming limestone rock were the major sources although in certain cases water and the
soil were demonstrated to be influential

Models were developed to predict cave radon concentrations within a single cave
However, these could not be transposed to predict radon concentrations in other caves in
the same region or other regions

The users of limestone caves were identified, their potential exposure times were
examined and legislation concerning their exposure was discussed Four groups were
identified as being at risk from radon while underground, and three groups were
identified as bemg at little risk Methods by which the risk from radon exposure can be
reduced were examined