Estimation of environmental gamma background radiation levels in Pakistan

For the purpose of preparing an environmental gamma radiation map of Pakistan, the geological materials exposed in the country were divided into eight different classes. Using average 238U, 232Th, and 40K content of these materials, total absorbed dose rate in these rocks was calculated. The dose rate in the environment ranged from 1 nGy h(-1) to 97 nGy h(-1) with a mean value of 59 nGy h(-1). These data are presented as a dose rate map of Pakistan. This map provides a usable regional picture of environmental gamma background radiation levels excluding cosmic radiation in Pakistan.