A RECONNAISSANCE SURVEY OF RADON IN SHOW CAVES IN IRELAND

A reconnaissance survey of radon gas concentrations and radon decay pr oduct concentrations in three Irish show caves was undertaken in Sprin g 1993. The caves, which are open to the public, are located in carbon iferous limestone regions in western and southern Ireland. Area monito ring of underground radon concentrations was conducted using passive C R-39 alpha track detectors positioned at sampling locations spatially distributed along the tourist routes. Continuous radon gas measurement s and decay product concentration measurements were carried out at sev eral of these locations. Radon gas concentrations ranged from 488 to 1 1 285 Bq/m(3) with significant variations both within and between cave systems. The equilibrium factor, F, ranged from 0.12 to 0.71 and vari ed within and between caves. Estimated effective doses to tour guides ranged from 2.0 to 7.4 mSv with tourists receiving doses from 3 to 12 mu Sv per visit. Through individual dose assesment of guides in one of the cave systems, area monitoring was shown to give a reasonable esti mate of the doses that tour guides are likely to receive. Copyright (C ) 1996 Elsevier Science Ltd.