Determination and Evaluation of Radiological Risk due to Indoor Radon Concentration Levels in Offices at a University Faculty in Ibadan Southwestern Nigeria

Abstract

Exposure to Radon (222Rn) especially indoors has been identified as an important factor that could result in a health hazard, especially increase in risk of lung cancer. Assessment of the risk can only be done with accurate information on the radon level to which the people are exposed. This work was designed to measure indoor radon level in some offices in the Faculty of Science, University of Ibadan, using electret passive environmental radon monitor (E-PERM). Measurements were made at 54 locations in five departments of the faculty. Indoor radon concentrations in these Departments were found to vary from 39.70 to 126.77 Bq·m−3 with an average mean of 65 ± 20 Bq·m−3. The results obtained showed variation with ventilation and type of building materials. The average indoor radon concentration obtained was below the indoor radon concentration action level (148 Bq·m−3) recommended by Environmental Protection Agency (EPA), hence no remedial action is required. The work however established the applicability of the technique for a much wider scope of indoor radon survey in the country.