Radon Unit Converter: Bq/m³ ↔ pCi/L
Convert radon concentrations between becquerels per cubic metre (Bq/m³), the SI unit used in Europe and by the WHO, and picocuries per litre (pCi/L), the unit used in the United States. The exact conversion is 1 pCi/L = 37 Bq/m³.
Exact conversion: 1 pCi/L = 37 Bq/m³ · 1 Bq/m³ ≈ 0.027 pCi/L
Official reference levels
Select a reference level to load it into the converter.
How does this compare?
Enter a value to compare it with the official reference levels.
Reference levels apply to long-term averages (at least 90 days of measurement), not to single short-term readings.
Frequently asked questions
How do I convert Bq/m³ to pCi/L?
Divide the value in Bq/m³ by 37. For example, the EU reference level of 300 Bq/m³ equals about 8.1 pCi/L.
How do I convert pCi/L to Bq/m³?
Multiply the value in pCi/L by 37. For example, the US EPA action level of 4 pCi/L equals 148 Bq/m³.
Why are there two different radon units?
The becquerel per cubic metre (Bq/m³) is the international SI unit, used in Europe and by the WHO. The picocurie per litre (pCi/L) is a traditional unit still used in the United States. Both measure the same thing: the activity concentration of radon in air.
What radon level is considered dangerous?
There is no threshold below which radon risk is zero — risk grows with concentration and time of exposure. The internationally agreed triggers for action are 100 Bq/m³ (WHO reference level), 4 pCi/L ≈ 148 Bq/m³ (US EPA action level) and 300 Bq/m³ (EU maximum reference level under Directive 2013/59/Euratom).
Above the reference level?
If your long-term average exceeds the reference level that applies to you, proven mitigation techniques can reduce it substantially.
Learn about mitigation