Employer's responsibility

The national reference level for indoor radon levels in workplaces is 300 Bq/m3.

If the measured radon level in a workplace is greater than 300 Bq/m3 employers must take remedial action as soon as is practicable, to protect the health of workers.

By law, if your workplace is one of the following, you must test it:

  • underground, including mines and show caves
  • on the ground floor or basement level in high radon areas
  • is one identified by the EPA as being liable to have radon concentrations above 300 Bq/m3


Article 66 of S.I. 30 of 2019 places a duty on employers in High Radon Areas to test for radon. The requirements of Article 66 are summarised as follows:

  1. The national reference level for indoor radon levels in air in workplaces is 300 Bq/m3.
  2. Radon tests should be carried out according to the EPA's Measurement Protocol for Homes and Workplaces.
  3. Where the results of a radon test exceed 300 Bq/m3, remedial measures must be taken to reduce the radon levels to below this national reference level.
  4. Following remedial work, further radon tests shall be carried out as soon as is practicable to determine whether the radon levels have been reduced to below the national reference level.
  5. The remedial work and the follow up radon tests must be completed within 12 months of the date of the original radon test that first identified radon levels above 300 Bq/m3.
  6. If, following remedial works, radon levels remain above 300 Bq/m3 the employer or self-employed person shall:
  • notify the Environmental Protection Agency
  • assess the radiation dose to workers and update this assessment in accordance with guidelines as may be issued by the EPA


In addition, under the Safety, Health and Welfare at Work Act 2005, every employer has a general duty to identify hazards in the workplace to minimise them. In line with Article 66 of S.I. 30 of 2019, all workplaces at ground floor and basement level in High Radon Areas must be tested for radon.

Because it is impossible to predict exactly where high radon levels will be found, it is recommended that every workplace should have a radon test carried out, even those located outside high radon areas.

Outdoor workplaces such as agriculture, transport, construction and fishing are unaffected by high levels of radon, and do not need to be tested.

More information on carrying out a test in your workplace can be found on our Radon Testing page.

For more information on reducing high levels, visit our Fixing A Radon Problem page.

Contact us

FreePhone: 1800 300 600
Email: radon@epa.ie