Radon decay products attached to clothes in a nuclear laboratory

A whole body counter determined the presence of radioactivities up to 21.8 kBq for 214Bi and up to 18.7 kBq for 214Pb attached to clothes of workers in a Nuclear Research Laboratory. A radon survey reveals that 80% of the monitoring areas have radon concentration values lower than 500 Bq m-3, while 10% of the sampling points with values bigger than 1 kBq m-3 correspond to the workers mentioned above. By exposing samples of 0.04 m2 clothes in a radon chamber, it was observed that radon decay products 214Bi and 214Pb were attached to them with an activity of 315-618 Bq per each kBq m-3 of Rn concentration additionally, fibres characterised with a low electrostatic build up showed the lower attachment