Health and Safety at Work Act 1974
Management of Health and Safety at Work Regulations 1999

This legislation requires employers, as far as reasonably practicable, to ensure the health and safety of employees and other people who have access to their work environment, for instance, members of the public in shops and schools. This includes a suitable and sufficient risk assessment, and taking appropriate action where necessary. UKHSA advises radon should be identified as a hazard if you have a workplace with one or more of the following circumstances:

  • it is a building in a radon Affected Area
  • it has a basement area that is occupied for more than about 50 hours each year
  • it is a mine, cave, or other underground environment
  • it has a suspected radon source such as ground water (e.g. treatment works) or geological samples.


If radon is an identified hazard, the workplace should be tested. Regulations apply if the radon level exceeds 300 Bq m-3 as an annual average in any area. The combination of the radon level, occupancy time, and workplace type will determine what action is required.

3. ACT

The Ionising Radiations Regulations 2017
The Ionising Radiations Regulations (Northern Ireland) 2017

Legislation requires employers to act if radon levels exceed the workplace threshold.

Where radon levels are satisfactory, the employer should simply keep a record of the results and review them after around ten years or if there are significant changes to the workplace structure or use.

Further advice is available from the HSE website.