ASSESSMENT OF ANNUAL EFFECTIVE DOSE OF GAMMA RADIATION IN VISAKHAPATNAM, ANDHRA PRADESH STATE, INDIA

Abstract

The living creatures on the earth are continuously exposed to radiation from extraterrestrial and terrestrial sources. These sources are caused to the ambient gamma dose rates which affect the dwellers. This study reveals the results of observations for a while about the dose in both indoor and outdoor atmospheres. The measurements were done in 17 locations in the Visakhapatnam district, Andhra Pradesh. The PM-1405 ambient radiation dosimeter was used to make these measurements, which is a portable detector based on the Geiger Muller counter. Annual effective dose (AED) was estimated using a standard method based on the measured average absorbed dose rates. The measured indoor absorbed dose rates in Visakhapatnam district 2021–June, ranged between 0.19±0.02 to 0.32±0.07 μSv.h-1, and the measured outdoor absorbed dose rates ranged from 0.15 ± 0.01 to 0.28±0.06 μSv.h-1 and the mean of indoor and outdoor measurements being 0.26±0.04 to 0.22±0.03 μSv.h-1 respectively. The indoor AED ranged between 0.93 to 1.57 mSv.y- 1 and the outdoor AED ranged from 0.18 to 0.34 mSv.y-1 with average values of 1.3 mSv.y-1 and 0.27 mSv.y-1 respectively. In the year 2018 – June, the indoor and outdoor absorbed dose rates, measurements ranged from 0.18±0.01 to 0.34±0.06 μSv.h-1 and 0.16 ± 0.02 to 0.31±0.06 μSv.h-1 and the mean values being 0.26±0.03 to 0.21±0.03 μSv.h-1. The indoor and outdoor AED ranged from 0.88 to 1.67 mSv.y-1 and 0.2 to 0.38 mSv.y-1 with average values of 1.28 mSv.y-1 and 0.26 mSv.y-1 respectively for the year 2018, External exposure to terrestrial radiation for members of the public should not exceed an effective dose of roughly 0.48 mSv per year, as recommended by the UNSCEAR 2000 report. As a result, it may be assumed that the general population faces signicant radiological hazards from terrestrial radiation caused by the natural radionuclides in the area.