2024 Yes Assessment of radiological risk associated with thoron gas at primary schools in Al-Najaf city, Iraq https://www.sciencedirect.com/science/article/pii/S0969804323005079?via%3Dihub Dosh, Rukia Jaber Europe Exposure Elementary (K-5) Radon Thoron Pin-hole dosimeter method CR-39 detector Annual effective dose Primary schools Al-Najaf city Thoron gas was measured in 100 primary schools in Al-Najaf, Iraq. Average concentrations and radiological risks were below global limits, indicating no significant health hazard from thoron exposure for children in these schools. 2024