Distribution of radon concentrations in child-care facilities in South Korea

Survey of Radon Concentrations in the University of Granada in Southern Spain

The objective of this pilot study was to gather and analyze data on radon concentrations in workplaces in three buildings of Granada University (Southern Spain) constructed in different centuries. All measurements were made at basement or ground floor level under normal use conditions except for one space (mineral store), in which measurements were compared between the door closed and open. Measurements were conducted during different time periods between October 2013 and March 2019 with a Radon-Scout PLUS portable Radonmonitor. The duration of continuous recordings at different sites ranged between 42 and 1104 h. Mean accumulated radon concentrations ranged between 12 and 95 Bq/m³, below the maximal level of 300 Bq/m³ set by the World Health Organization (WHO). Relatively high values were recorded in the oldest building (15th century), which was also poorly ventilated. Ventilation appeared to be an important factor in reducing radon levels, especially in areas less exposed to radon, such as Southern Spain.

INDOOR RADON CONCENTRATION AND ANNUAL EFFECTIVE DOSE IN 56 RADIATION AREAS AT 34 MEDICAL INSTITUTIONS IN SOUTH KOREA

This study aims to measure the indoor radon concentration (IRC) of 56 radiation areas at 34 medical institutions to assess their adequacy as required by the South Korean Ministry of Environment and international standards, and calculate the annual effective dose (AED) of individuals in radiation-related professions at each medical institution. The study was conducted for 9 months and the AED was calculated according to the South Korean Nuclear Safety and Security Commission's equation. The environmental factors that can affect IRC were analyzed by medical institution, floor level, province and ventilation system. The IRC of eight radiation areas exceeded the recommendation of the International Commission on Radiological Protection, with max-AED and min-AED showing a difference of 1.42 mSv/y. Therefore, all radiation areas that exceed the recommended limits must set up preventative measures to minimize exposure. Furthermore, a systematic management plan involving the issuance of radon test reports is required.

Radiometric evaluation of indoor radon levels with influence of building characteristics in residential homes from southwestern Nigeria

Indoor radon (²²²Rn) measurements were carried out using solid state nuclear track detectors (SSNTD) in some dwellings from southwestern Nigeria. This was aimed at statistically assessing influence of building characteristics on the measured radon and estimating excess lifetime cancer risks (ELCR). The measured radon concentrations followed lognormal distribution and were significantly influenced by some building properties. The arithmetic mean (1.60 mSv) of annual effective doses (AEDs) due to indoor radon was observed to be higher than the world average level (1.15 mSv) but less than lower limit (3 mSv) of International Commission on Radiological Protection (ICRP). The evaluated excess lifetime cancer risk ranged from 1.5 to 28.1 (MPy)^-1 with an average value of 6.3 (MPy)^-1, indicating that after exposure to indoor radon for 70 years, 6 people in every 1000 are likely to suffer the risk of developing lung cancer. Adequate ventilation systems were recommended for houses with high level of radon to avoid unnecessary exposure to radon. However, the investigated data would form important component of the database required to set up guidelines and policy of controlling radon at home.

Indoor radon concentration in Korea residential environments

The purpose of this study is to provide basic data for the evaluation and management of health effects with respect to exposure to radon within residential environments in South Korea. It is part of a case-control study to develop a management plan based on indoor radon exposure levels and assess their impact on health. To investigate the long-term cumulative concentration levels of radon, 599 patients who have respiratory diseases were recruited in South Korea, and alpha track detectors were installed in their residences for a period of 3 months from mid-2015 to late 2016. A survey was then conducted to determine the factors affecting the radon concentration. The radon concentration levels were analyzed in conjunction with the survey results. The results show that the arithmetic mean of the radon concentrations in domestic residences was in the range of 70.8 ± 65.2 Bq/m³. An analysis of covariance (ANCOVA) was performed to identify the environmental factors affecting the radon concentration and contributing to variations in the residential radon concentration based on the height of the residence. The results show that the contribution of the local environmental factor to the variation in radon concentration (p < 0.05) was greater than that of other environmental factors. Although no statistically significant difference was found with regard to the construction year of the building before the control (p > 0.05), the same was found with regard to the construction year after the control (p < 0.05).