ASSESSMENT OF INDOOR AND OUTDOOR RADIATION DOSE LEVELS IN DELTA STATE POLYTECHNIC, OGWASHI-UKU, DELTA STATE, NIGERIA

This study assessed the indoor and outdoor radiation dose levels of twelve (12) laboratories of Delta State Polytechnic, Ogwashi-Uku using a handheld inspector survey meter and estimation revealed that the average BIR, average annual equivalent dose rate (EDR), average annual absorbed dose rate (ADR), average annual effective dose equivalent (AEDE), average excess lifetime cancer risk (ELCR) is 0.0116 mR/hr, 0.9733 mSv/yr, 100.69 nGy/hr, 0.4940 mSv/yr and 1.755. Dose to organs showed that the testes received the highest dose, while the liver received the lowest dose indoors and outdoors respectively. In general, indoor and outdoor BIR, ED, AD, and AEDE values ​​are less than the recommended limit of unity (1 mSv/yr) for public exposure (ICRP). ELCR for indoor and outdoor is above the world permissible limit of 0.29×10-3. The calculated ELCR in the study area is 1:29719 (about 33 in 1 million) indoors and 1:115735 (9 in 1 million) outdoors. Although the average value for ELCR in this study is high further analysis and studies need to be carried out to ascertain the risk of staff and students to cancer.  