Glossary · Health & indoor air
Radon units: Bq/m³ and pCi/L
Also called: Bq/m³ · Bq/m3 · becquerels per cubic metre · becquerels per cubic meter · becquerel · becquerels
Canada measures radon in becquerels per cubic metre (Bq/m³) and the US in picocuries per litre (pCi/L); 1 pCi/L equals 37 Bq/m³.
What it means
Both units describe how many radioactive decays happen in a volume of air. To convert, multiply pCi/L by 37 to get Bq/m³, or divide Bq/m³ by 37 to get pCi/L. Health Canada's 200 Bq/m³ guideline is about 5.4 pCi/L, while EPA's 4 pCi/L action level is about 148 Bq/m³, so the US level is lower.
Why it matters in an audit
Test kits and lab reports may use either unit, and converting correctly tells you which guideline your result falls under.
Typical numbers
Reference values with their sources. Your energy advisor’s report gives the figure for your own house.
| What | Value | Source |
|---|---|---|
| Conversion | 1 pCi/L = 37 Bq/m³ exactly (1 curie = 3.7 × 10¹⁰ becquerels) | nist.gov ↗ |
| Health Canada guideline in US units | 200 Bq/m³ ≈ 5.4 pCi/L | Arithmetic |
| EPA action level in metric units | 4 pCi/L = 148 Bq/m³ (EPA rounds to 150) | epa.gov ↗ |
| EPA 'consider fixing' level | 2 pCi/L = 74 Bq/m³ (EPA rounds to 75) | epa.gov ↗ |