South Korea’s nuclear safety experts have released an updated nationwide map of natural background radiation levels following a comprehensive four-year survey covering 125,100 kilometers.
Extensive Nationwide Monitoring Effort
The Korea Institute of Nuclear Safety (KINS) research team measured radiation at 723,052 locations across the country. This detailed data compilation, published on January 8 in a national science journal, tracks natural sources such as soil uranium, radon, thorium, and potassium.
These everyday exposures contribute to an average annual radiation dose of 3.1 millisieverts (mSv) for the public—equivalent to about 30 chest X-rays.
Advanced Data Collection Techniques
To capture precise measurements, the team equipped vehicles with specialized devices. While stationary thick deposits proved challenging, mobile sensors effectively gathered data on airborne elements like radon, thorium, and potassium across vast road networks.
The survey integrated ion chamber readings and radioactive nuclide detection, processing environmental data through KINS’s Nuclear Safety Information System. Since 2013, this approach has mapped the entire nation, achieving 10-fold accuracy within 60-kilometer radii.
Key Findings and Implications
A KINS senior researcher highlighted the scope: “Nationwide, data comes from 1.3 million measurement points. Regional variations required dense coverage, turning vehicles through diverse areas to compile accurate mapping data.”
The researcher added, “With this baseline data, future trends—whether radiation levels rise or fall—can be reliably confirmed.”
Average soil concentrations registered uranium at 51.2 becquerels per kilogram (Bq/kg), thorium at 58.9 Bq/kg, and potassium at 877 Bq/kg. The overall average dose rate stands at 131 nanosieverts per hour (nSv/h).
This updated map enables better public exposure averages and informs national radiation policies.
