​​​​​​​Radon monitoring and mitigation measures in Council properties including Caithness House in Wick

20th August 2025

Highland Council advise that recent radon testing carried out across its estate has identified elevated levels of radon gas in isolated areas of nine properties. These findings follow a comprehensive monitoring programme involving 135 non-domestic workplaces and public buildings, in line with UK Health and Safety legislation.

The affected properties are:

Caithness House
Lochaber Leisure Centre
Highland Council Headquarters
Highland Archive Centre
Dalneigh Primary School
Kilchuimen Academy
Crossroads Primary School
Inverness High School
North Kessock Primary School

Council officials have reassured the building users that the levels detected do not pose an immediate health risk. All buildings remain open and operational, and precautionary measures have already been taken to reduce potential exposure. These include increased ventilation, sealing of entry points, and restricting access to specific areas.

Finlay MacDonald, Chief Officer Property and Assets said: "We are working closely with specialist consultants to ensure that all necessary mitigation measures are put in place. Our priority is the safety of building users, and we are confident that the steps being taken will effectively manage radon levels."

Dr Jenny Wares, Consultant in Public Health Medicine with NHS Highland said: "Radon is present in all air, and we all breathe in radon every day, usually at very low levels. However, exposure to higher levels over many years can increase the risk of lung cancer especially in those who currently smoke or who smoked in the past. Whilst the increased risk to pupils or staff caused by exposure to radon while at school or the workplace is very low, measures have been put in place to reduce the risk of exposure."

Long-term mitigation plans underway

Tailored mitigation strategies are being developed for each site, including the installation of active sump and fan systems, positive pressure ventilation, and further structural sealing. Post-installation testing will be carried out to confirm the effectiveness of these measures, and ongoing monitoring will ensure continued safety.

Community awareness encouraged

Radon is a naturally occurring gas that can accumulate in buildings, particularly those with limited ventilation. Highland Council encourages residents to learn more about radon and consider testing their homes. Guidance is available from the UK Health Security Agency: https://www.ukradon.org (external link) .

Parents, staff and partner agencies at the affected properties have been informed and an FAQ document has also been provided (see below). Further information about radon or the health effects associated with radon can is available on the website https://www.ukradon.org/ (external link) .

The Council will continue to keep building users, and the wider community informed throughout the assessment and mitigation process.

Radon - frequently asked questions

1. What is radon?

Radon is a colourless, odourless radioactive gas. It is formed by the radioactive decay of the small amounts of uranium that occur naturally in all rocks and soils. It is present in all air, and everyone breathes radon in every day, usually at low levels.

In open air, it disperses very quickly but can accumulate in buildings. The amount of radon in the indoor air depends on its location, structure, ventilation, and heating and how the building is used. Radon is present in all buildings, including homes, so we all breathe it in throughout our lives.

For most UK residents, radon accounts for about half of their total annual radiation dose. The average level in UK homes is 20 Becquerels per cubic metre of indoor air (Bq/m3).

2. What are the health effects of radon?

Radon produces a radioactive dust in the air we breathe. The dust is trapped in our airways and emits radiation that damages the inside of our lungs. This damage, like the damage caused by smoking, increases our risk of lung cancer. The risk of lung cancer is highest for people who smoke tobacco and have high radon exposures. If you smoke tobacco, quitting is the most effective way of reducing the risk of lung cancer. The risk of lung cancer from exposure to radon in lifetime non-smokers is small and many times lower than the risk of lung cancer if you smoke tobacco.

3. What is the definition of ‘significant long-term exposure' to radon?

Everyone is exposed to radon throughout their lifetime - it is unavoidable (exposure is the combination of the radon level and the duration). With radon we think of exposure duration in terms of many years, usually decades. Hence the action levels are set at radon concentrations where measures are justified to control radon exposure and reduce the risk of adverse health effects, assuming that people would be exposed to it over the long term.

4. What is the radon ‘Action' Levels’?

Radiation protection standards in workplaces are set by the Ionising Radiations Regulations 2017, which apply if annual average radon levels are above 300 Bq/m3. If levels exceed this concentration, action should be taken to reduce radiation exposure to staff and other occupants. Usually this is done by lowering the radon level. There is no way to eliminate all radon from the world. However, by putting in place some minor building work the levels can be reduced below the action level so that the risk becomes very small.

5. How do you know where to test for radon?

The UK Health Security Agency (UKHSA) have published reports containing radon affected area maps. These identify areas with a higher probability of radon concentration exceeding the radon action level. The maps for Scotland are available here http://www.ukradon.org/information/ukmaps (external link)

6. Why were Council properties monitored for radon?

As the Highlands were identified as having radon-affected areas the Council, like other employers, is required to monitor its premises for radon and act accordingly if levels are found to be above the action level. The Council already has a radon monitoring programme in place, and 2025, further testing of a 135 premises was carried out which identified 9 premises as requiring a radon gas risk assessment and remedial works to lower the radon levels.

7. How was the radon level measured?

Radon levels can vary between adjacent buildings and even in a room, radon levels can vary from day to day and hour to hour. Because of these fluctuations, radon levels are normally measured over a three-month period with the use of small plastic detectors.

8. I work at/my children attend a premises identified as having an elevated level of radon so what is the risk?

A person’s risk of getting lung cancer from radon is dependent on the following three factors; the duration of exposure, the level of radon and whether a person smokes. The increased risk to staff members or children from radon exposure at the premises is very small. The Council has taken short term measures such as increasing ventilation to reduce radon levels and longer- term remedial work will be carried out to limit exposure to radon in the premises.

The risk is higher in those who also smoke, so for smokers the most effective way of reducing the risk further is by stopping smoking.

9. What about the rest of the community?

All employers and landlords are obliged to check if their properties are at risk. A first step is to check radon maps available at the website http://www.ukradon.org/ (external link) . They may also need to carry out testing which can be simply arranged through the same website at minimal cost (around £25 for a radon detector).

Householders are encouraged to check the maps available at the website http://www.ukradon.org/ (external link) . The http://www.ukradon.org/ (external link) website also offers a detailed map check on individual properties for around £4. If the house is in an area at risk from radon, then monitoring should be carried out. This can be simply arranged through the same website at minimal cost (around £52.80 for a radon test pack).

10. When will the next update be issued?

An update will be issued to all property relevant persons and Head Teachers once further monitoring results are received and long-term remedial work is complete.

11. Who can I contact at the Council to discuss issues with radon at any of the nine properties?

School premises: contact the Head Teacher

Council offices: contact your Line Manager or Responsible Premises Officer (RPO).

12. Who can I contact if I want further information on radon or to discuss risks?

UK Health Security Agency can be contacted directly if you wish to discuss any of the items further on their website http://www.ukradon.org/contactform (external link) .

General information about radon and health risks can be found at http://www.ukradon.org/ (external link) .