Mlay, GermanaMakundi, Ismael2018-05-232018-05-232018-05-230856-1761e-ISSN 2507-7961http://hdl.handle.net/20.500.11810/4721This study aimed to assess indoor radon concentrations in the vicinity of the Manyoni Uranium Deposit in Singida. The concentrations were measured for two months in 32 houses in the vicinity of Manyoni Uranium Deposit and 9 houses at Manyoni town using a portable radon gas monitor (Alpha –GUARDTM). The radon concentrations ranged from 27±3 to 518±28 Bq/m3with the overall mean of 166±12 Bq/m3 which is above recommended values of 100 Bq/m3 and 148 Bq/m3 set by WHO (World Health Organization) and EPA (Environmental Protection Agency's), respectively. The overall mean of indoor radon concentrations from each village were Kipondoda (169±13 Bq/m3), Muhalala (177±16 Bq/m3), Mwanzi, (287±13 Bq/m3), Mitoo (325±21 Bq/m3) and Majengo (377±23 Bq/m3) which exceed the limit set by WHO (World Health Organization) and EPA (Environmental Protection Agency). The value of 325±21 Bq/m3 and 377±23 Bq/m3 from Mitoo and Majengo respectively, exceed the limit of 300 Bq/m3 recommended by ICRP (International Commission on Radiation Protection). Thus there is a non-negligible probability of incurring stochastic effects for people living in the vicinity of Manyoni Uranium mine. It is recommended that human activities should be controlled near the uranium deposits and dwelings should be well ventilated.enIndoor radon, Concentrations, Cancer, Manyoni uranium deposit, Alpha –GUARD.Journal Article