Occupational Radon Assessment in Underground Storage Facilities in Saudi Arabia

An occupational radon assessment was conducted at five underground storage facilities in the Kingdom of Saudi Arabia to evaluate the radon concentration and determine if remedial action is required to ameliorate conditions and ensure compliance with international guidance on acceptable radon levels in working environments. The assessment was carried out in four operational areas in the underground storage facilities routinely occupied or visited by workers. Initial radon concentrations were obtained using 293 passive CR-39 Nuclear Track Detector (NTD) radon dosimeters installed in the four operational areas for all the underground storage facilities. The detectors were left in place for 12 mo. As some of the radon measurements exceeded the International Atomic Energy Agency reference level of 1,000 Bq m(-3) for radon in workplaces, a follow-up assessment was conducted using a real-time monitoring device in locations where high radon levels were observed. The measured radon concentrations in the four operational areas in three of the five underground storage facilities were below the reference level, and in the remaining two storage facilities, low ventilation rates in one operational area were identified as the principal cause of elevated radon concentrations. Notwithstanding, the potential radiation dose from radon exposure was determined to be well below the International Commission on Radiation Protection reference annual dose level of 10 mSv in all five underground storage facilities. Radon exposure to workers in all the underground storage facilities was found to be within the reference dose level for workplaces and does not pose an acute health risk.