Canadian RadonServices Index
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Convert radon units: pCi/L and Bq/m³

Convert a radon reading between pCi/L and Bq/m³, with the conversion factor and its source, and see where the result sits against Canada's guideline.

Tool

Convert radon units: pCi/L and Bq/m³

Method

The tool follows the steps on this page, in order. You can follow them with a pen. Work it out by hand

One picocurie per litre (pCi/L) is 37 becquerels per cubic metre (Bq/m³). Multiply pCi/L by 37 to get Bq/m³, and divide Bq/m³ by 37 to get pCi/L. Indoor radon in Canada is normally reported in Bq/m³. You will meet pCi/L in US radon information, such as a US-made device or a US lab report.

Multiply pCi/L by the factor to get Bq/m³, and divide to go back

Take your reading in pCi/L and multiply it by 37. The answer is the same reading in Bq/m³. To go the other way, take your reading in Bq/m³ and divide it by 37. The answer is the reading in pCi/L. These six rows show the arithmetic at six points, including Canada’s guideline.

  • 1 pCi/L is 37 Bq/m³
  • 2.7 pCi/L is about 100 Bq/m³
  • 4 pCi/L is 148 Bq/m³
  • 5.4 pCi/L is about 200 Bq/m³
  • 10.8 pCi/L is about 400 Bq/m³
  • 27 pCi/L is 1,000 Bq/m³

The pCi/L values in these rows are rounded to one decimal place. Canada’s 200 Bq/m³ divided by 37 is 5.405, which the rows show as 5.4. Find out what your number means and whether the test was long enough.

The factor comes from Health Canada’s measurement guide

The factor of 37 Bq/m³ per pCi/L comes from Health Canada’s guide for radon measurements in homes, dated 22 May 2026. It is the same factor in both directions. We checked it against that guide on 18 September 2026. Every figure on this site carries its source and the date we checked it. See how the Index chooses and dates its sources.

Canada’s guideline is set in Bq/m³, so compare your reading in that unit

Canada’s guideline is 200 Bq/m³, set in that unit. A reading in pCi/L and its converted value are the same amount of radon in two units. Converting a reading does not move the guideline. A reading of 5.4 pCi/L is 199.8 Bq/m³, just under the guideline and well within the plus or minus 25% range around it.

The United States uses a different level. The US EPA action level is 4 pCi/L, about 148 Bq/m³, which the EPA commonly rounds to 150 Bq/m³. The EPA recommends fixing at or above 4 pCi/L and considering action between 2 and 4 pCi/L. A US page’s 150 Bq/m³ and Canada’s 200 Bq/m³ are two different levels, each set by its own agency. See how Canada’s guideline compares with WHO’s and the US level.

A converted reading is only as good as the test behind it

Health Canada writes the guideline for a long-term average. A test of 91 days or longer is long-term, and anything shorter is short-term. A short-term reading converted into Bq/m³ is still a short-term reading. It does not tell you where your home sits against the guideline.

Converting also leaves the uncertainty where it was. Repeated results may vary by up to plus or minus 25%. A reading of 4 pCi/L and its conversion of 148 Bq/m³ carry the same range. See how to run a long-term test.