INSTITU MEASUREMENT OF GAMMA RADIATION DOSE LEVEL OF SCRAP METAL MARKETS IN JOS METROPOLIS- PLATEAU STATE, NIGERIA

Abstract

In this research work, a survey of gamma radiation dose level in scrap metals from scrap metal markets in Jos metropolis was carried out using the gamma scout radiation detector. Measurement were taken from eleven randomly identified scrap metals market in Jos. Results from this study show that the mean background radiation was 0.213 µSv/hr with a maximum and minimum values of 0.299µSv/hr and 0.165 µSv/hr respectively. The maximum background_ADR(Background Annual Dose Rate) was 47.656µSv/yr and was observed in YTM and GCFGR markets which were mixed scraps and automobile scrap metals in nature. These values are higher than standard background radiation of 0.133µSv/hr and are below the ICRP maximum permissible limit of 0.57 µSv/hr. The values of the measured annual radiation dose rate for all the scrap markets[Gamma radiation Annual Dose Rate (A_ADR), Beta Annual Dose Rate (B_ADR), Alpha radiation Annual Dose Rate (C_ADR)] were lower than the ICRP recommended limit of 1000 µSv/yr (1 mSv/yr) for the public and 20000µSv/yr for occupationally exposed work personnel. The studied areas are confirmed to be within the permissible limit and so may not pose any significant radiological health effects or hazards on the general public and the workers. These findings suggest regular assessment should be carried out at these areas to ensure that exposures are kept as low as reasonably achievable and within the tolerable limit of exposures.