During the period August 1993-0ctober 1994 a study was undertaken throughout British Telecommunications pie to assess occupational exposure to radon. This paper is concerned only with that portion of the work concerned with underground structures. The results show that radon can build up to very high concentrations in manholes and implies a significant risk to those who need to work in them.
The workplaces located in southern (18 places) and central Finland. The total amount of workrooms measured was 87. The mean concentration of radon was 254 Bq/m3 (range from 12 to 1647 Bq/m3) during working hours. The calculated radon entry rates varied from 2 to 4780 kBq/h. The measured air exchange rates varied from 0.1 to 13.3 l/h and calculated ventilation flow rates varied from 30 to 55200 m3/h. Radon concentration was found to depend on the type of foundation, whereas types of ventilation or the ventilation flow rates did not correlate significantly with the concentrations of radon.
Login