Assessment of Indoor and Outdoor Background Radiation Levels at School of Technology, Kano State Polytechnic, Kano State-Nigeria

A Survey taken by the world health organization (WHO) and the international commission on radiation protection (ICRP) shows that residents of temperate climate spends only about 20% of their time outdoor and about 80% indoors and certain materials use for the construction of such buildings (rocks, soils, tiles etc) are known to be radioactive, and exposure to such radiation results in critical health challenges. Assessment of indoor and outdoor background ionizing radiation level at School of Technology, Kano State Polytechnic, Nigeria was carried out using a digital radiation meter (Radiation Alert Inspector). A total of 49 areas were surveyed and the results obtained showed that the annual indoor reading were highest at Compounding Lab. (2.368±0.35 mSv/yr) and Old Chemistry Lab. (2.169±0.35 mSv/yr), and lowest at New Biology Lab. (1.219±0.21 mSv/yr) and Press Workshop (1.303±0.35 mSv/yr). For the outdoor areas, SOT ring road was found to have the highest value of 0.557±0.17 mSv/yr, while Zoological Garden has the lowest effective value of 0.280±0.05 mSv/yr. For the lecture venues, Auditorium has the highest indoor annual equivalent dose of 2.060±0.49 mSv/yr, while H-Block ND I Textile Class recorded the lowest values of 1.275±0.27 mSv/yr. Base on the aforementioned findings, it was deduced that radiation levels are within the permissible radiation limit as stipulated by the ICRP and UNSCEAR of 2.4 mSv/yr and thus, SOT Kano is radiologically safe.

Keywords
Indoor and outdoor; background radiation; equivalent dose; Digital Radiation meter