Gamma background radiation in Yazd province, a preliminary report

ABSTRACT

There are relatively rich uranium mines in regions of Saghand and Bafgh in Yazd province. This survey was carried out to provide a map of ambient gamma radiation of Yazd province and the probable effects of the existence of these mines on background radiation dose rates. The measurements of the outdoor and indoor-environmental exposures [including cosmic and terrestrial components] were accomplished by a portable Geiger Muller detector in the five areas in each of eight big cities of Yazd province. The average exposure rates of indoor and outdoor ambient of Yazd province were 13.9 +/- 0.7 microRh[-1] and 11.6 +/- 0.8 microRh-1 respectively. The average dose rates in air, resulting from gamma background radiation of indoor and outdoor were 122 +/- 6.8 nSvh[-1] and 101.4 +/- 7.4 nSvh[-1] respectively. The annual average of equivalent dose in air was found to be 1.03 +/- 0.05 mSv, and the annual average of effective dose was 0.72 mSv. The results of this study in comparison with the same measurements in some other cities in Iran such as Isfahan and Tabriz, proves that the existence of uranium mines doesn't affect gamma background radiation of Yazd province