Use workplace guidance
Do not apply domestic advice as a workplace compliance checklist. HSE explains that the Ionising Radiations Regulations 2017 apply where radon is present above 300 Bq/m³ as an annual average, a different figure from the 200 Bq/m³ domestic Action Level. Employers consider radon through their risk assessment, and the right response depends on the premises and measured levels.
Identify relevant spaces
HSE says that for most above-ground workplaces in a radon Affected Area, the risk assessment should include radon measurements in appropriate ground-floor rooms. Occupied below-ground workplaces, those used for more than about 50 hours a year, should be measured too. Record the address, occupied floors, below-ground areas and how spaces are used, and provide any previous measurements or mitigation records to the person advising on the assessment.
Plan a suitable measurement programme
A workplace can have different occupancy patterns and room layouts from a home. Agree detector numbers, locations, dates and interpretation with a suitable provider. Preserve the full report rather than only a headline number.
Take advice on the result
Where radon is above 300 Bq/m³, HSE says the employer may need to take immediate steps to manage exposure while deciding whether to reduce levels by engineered means. HSE’s guidance explains when further controls and specialist radiation protection advice are needed. Consult that source and an appropriate adviser for your circumstances. This article is an introduction, not a compliance determination.
Sources & further reading
HSE: radon in the workplace ↗General guidance for property owners. Check the original source and obtain advice specific to your building.