Radon levels and dose estimation in some hot spring hotels

Guangdong is one of the provinces that have most hot springs in China. This paper presents the results of radon measurements in hot spring hotels of Guangdong province by using NR-667A continuous radon detector. Radon concentrations were measured in hotel rooms with attached bathrooms, tap waters and outdoors air. Radon concentrations were 53.4-292.5 Bq/L in the hot spring water, and 17.2-190.9 Bq/m3 in outdoor air. In the bathrooms radon contents ranged from 29.3 to 911.6Bq/m3 without using hot spring water, but after bathing 15 min and 30 min with hot spring water they reached 63.6-1917.8 Bq/m3 and 79.2-2710.7 Bq/m3 respectively. Radon concentrations in bedrooms ranged from 32.7 to 4337.8 Bq/m3 without natural and mechanical ventilation, and they could reduce from the highest to 137.6-213.3 Bq/m3 after 1h ventilation. Indoor radon accumulation with bathing time was also presented. The effective dosages of radon to hotel workers and tourists are estimated.