Establishing the traceability of radioactivity standards to the National Institute of Standards and Technology (NIST)

Uranium content of soil samples collected from different states of India, namely Uttar Prades, Rajasthan and Kerala has been estimated. The areas cover the normal background area, high background area and dumpyards of fertilizer factory and thermal power plant. Plastic sheets were used as a detector for the registration of fission tracks resulting from the (n, f) reaction on²³⁵U present in the sample due to the thermal neutrons from a nuclear reactor. The uranium concentration has been found to vary from 0.24 to 9.20 μg/g in various soil samples. Higher levels of uranium were found in the vicinity of a coal fired power plant. The present results may be useful for the radiation hygiene.