effective dose from natural background radiation in keffi and akwanga towns, central nigeria

background: human is exposed to radiation in their environment with or without their consent and the exposure to natural background radiation is an unpreventable event on earth. materials and methods: an in situ assessment of the indoor and outdoor background radiation in akwanga and keffi towns of nasarawa state nigeria was carried out using a halogen-quenched geiger muller (gm) detector (inspector alert nuclear radiation monitor sn: 3544). each of these towns was divided into at least 20 sampling areas where at least ten readings were taken in order to have a reliable data. results: the mean indoor and outdoor annual effective dose of akwanga were 1.29± 0.13msv/yr and 0.31±0.04 msv/yr respectively and that of keffi were 1.08± 0.15msv/yr and 0.25±0.04 msv/yr respectively. the radiation levels in both highly populated towns were found to be within the safe limit for areas of normal background set by unscear (2.4 msv/yr). conclusion: these results would serve as a baseline upon which other exposures would be assessed and in the future, serve as reference for dosimetry and decontamination in situations of radiation poisoning of these towns.