Ambient indoor/outdoor gamma radiation dose rates in the city and at high altitudes of Muzaffarabad (Azad Kashmir)

Abstract

Preliminary results of ambient indoor/outdoor gamma dose rates measured for Muzaffarabad city, the state capital of Azad Kashmir, are presented. Measurements of indoor/outdoor environmental exposures were carried out using a portable Ludlum Model 19 Micrometer. Effect of altitude on measured values of gamma dose rates has also been investigated. Besides measuring the gamma dose rates for indoor and open environment, measurements have also been taken within two coal mines. Effects of lithology on gamma dose rates have also been investigated. For outdoor measurements, minimum and maximum gamma dose rates were found as 533 ± 4.33 and 1,143 ± 2.96 μGy y−1, while for indoor environment minimum and maximum gamma dose rate value were found as 533 ± 4.33 and 979 ± 3.2 μGy y−1. Average values of indoor and outdoor gamma dose rates were found as 761 ± 3.62 and 710 ± 3.75 μGy y−1. Gamma dose rates have also been calculated with altitude variations. Measured values of gamma dose rates show a weak positive correlation with altitude. For measurements made in coal mines, maximum gamma doses rate value was found as 3,490 ± 1.69 μGy y−1, situated at a height of 1,098 m, located at Sangri Mera. Results obtained from the current study show that annual effective doses from gamma radiation exposure does not pose health threat to the population of district Muzaffarabad.