An indoor radon survey of the X-ray rooms of Mexico City hospitals

This paper presents the results of measurements of indoor radon concentrations in the X-ray rooms of a selection of hospitals in the metropolitan area of Mexico City. The metropolitan area of Mexico City is Mexico's largest metropolitan area by population; the number of patients requiring the use of X-rays is also the highest. An understanding of indoor radon concentrations in X-ray rooms is necessary for the estimation of the radiological risk to which patients, radiologists and medical technicians are exposed. The indoor radon concentrations were monitored for a period of six months using nuclear track detectors (NTD) consisting of a closed-end cup system with CR-39 (Lantrack (R)) polycarbonate as detector material. The indoor radon concentrations were found to be between 75 and 170 Bq m(-3), below the USEPA-recommended indoor radon action level for working places of 400 Bq m(-3). It is hoped that the results of this study will contribute to the establishment of recommended action levels by the Mexican regulatory authorities responsible for nuclear safety.