The short answer
A typical domestic radon test uses two detectors, usually in a living area and an occupied bedroom, for three months. A validated laboratory analyses them and reports an estimated annual average.
When should you test?
Check official radon information for the property. UKHSA recommends measuring radon in homes in radon Affected Areas. It also says every occupied basement (one used for more than 50 hours a year) should be monitored, whatever the area’s mapped radon potential.
How a home test works
Order a domestic measurement pack from a validated laboratory. Follow its placement instructions and record the start and end dates. Continue using the home normally during the test and report unusual occupancy or building work that might affect interpretation.
Why three months?
Radon levels change with weather, ventilation and daily conditions. A longer test smooths out that variation. Short tests can provide an initial indication but carry more uncertainty and should not automatically be treated as an annual average.
What happens when you receive the result?
Check the measured units, testing period and laboratory comments. If the result calls for reduction, share the full report with a mitigation specialist. After any work, arrange another measurement to verify the effect; UKradon says a free re-measurement is sometimes available to check remedial work.
What to check before ordering
Ask the provider what the testing charge includes. This website does not sell or analyse detector kits.
- Is the laboratory validated for domestic radon measurement?
- Does the price include two detectors, analysis, VAT and return postage?
- When should you expect the report after returning the detectors?
- Is advice on interpreting the result included?
Sources & further reading
UKHSA: measuring radon in homes ↗UKHSA: Action Level and Target Level ↗Checked 13 September 2026. General property guidance; use the original source and seek professional advice for your circumstances.