Long-term monitoring of outdoor natural gamma absorbed dose rate in air in Bengaluru, Karnataka, India

Abstract

Abstract This research forms a part of the comprehensive Indian Environmental Radiation Monitoring Network program, focusing on the continuous measurement of absorbed dose rate in outdoor air due to natural gamma radiation (cosmic and terrestrial) in Bengaluru, Karnataka, India. Over the course of a decade (2013–2023), data were collected from 41 monitoring locations in the city using permanently field-installed Geiger-Mueller detector-based environmental radiation monitors. This paper presents an analysis of the extensive long-term monitoring results. The mean absorbed gamma dose rate in outdoor air across the monitoring locations ranged from 84 ± 9 to 156 ± 4 nGy.h−1, with a calculated mean value of 124 ± 15 nGy.h−1. The estimated mean annual effective dose due to outdoor natural gamma radiation varied from 0.10 ± 0.01 to 0.19 ± 0.01 mSv.y−1, with an overall mean of 0.15 ± 0.02 mSv.y−1.