Overview

• Approved in April and effective since May, CSN Instruction IS-47 aligns Spain’s radon monitoring requirements with EU reference levels and national building codes.
• Workplaces in designated zones must measure indoor radon for a minimum of three months, preferably between October and May to capture seasonal variations.
• About 1,700 of Spain’s 4,000 municipalities are classified as high priority, including 91% of Galicia, 78% of Extremadura, 59% of Madrid and 14% of Asturias.
• Radon is a colorless, odorless gas from uranium decay that the World Health Organization ranks as the second leading cause of lung cancer after smoking and the top risk for non-smokers.
• This week’s publication of a comprehensive municipal list and interactive map guides employers in identifying whether they must comply with the new testing obligations.