(Mae'r tudalennau hyn yn Saesneg yn unig ar hyn o bryd, yn bennaf oherwydd eu natur dechnegol)
What is Radon
Radon is a natural radioactive gas which seeps into buildings from minute amounts of uranium that are present in all rocks, soils, bricks and concrete.
The highest radon concentrations are usually found in underground spaces such as basements, caves and mines but high concentrations can also be found in the ground floor of buildings. Radon levels can vary daily and seasonally as a result of temperature differences between indoors and outdoors. Radon levels in winter also tend to be higher due to reduced ventilation and the effects of central heating drawing air up from the ground below.
Most radon gas breathed in is immediately exhaled and presents little hazard. However, some radon decay products may attach themselves to atmospheric dust and water droplets which when breathed in, becoming lodged in the lungs and airways. Long term exposure to high radon concentrations increases the risk of lung cancer with health studies showing that radon is responsible for 3-5% of all lung cancers in the UK.
The Management of Health and Safety at Work Regulations require employers to protect staff from high radon levels. Where indicative measurements of radon exceed the action level of 400 Bq m-3, the employer must take steps to assess the risk and implement controls to protect the health and safety of its employees.
As some areas of Wales are affected by radon and some University buildings contain work areas that are either wholly or partially below ground, Bangor University was one of the first Universities nationally to undertake a radon survey to identify radon affected areas.
Identifying Radon Affected Areas
As part of this process, the University initially carried out a Post Code Survey, using a service provided by the Health Protection Agency (HPA) which links to their records of known radon affected areas.
The data from the Post Code Survey was then used in conjunction with the findings of an in-house study which utilised local knowledge to identify areas of the University estate that were either wholly or partially below ground.
Radon monitors, provided by the HPA were then placed in these areas for three months before being sent to the HPA for analysis. The results were then compared with the action levels stipulated in the Ionising Radiation Regulations and action taken where necessary.
What was Found?
As a small number of areas showed slightly heightened radon levels local procedures have been put in place to either monitor occupancy or improve ventilation. Where identified, further and more detailed surveys will be undertaken over the coming weeks and months to ensure potential problems with radon are fully understood.
Should I worry?
The effects of radon will vary dependent on:
Radon concentration levels.
Duration of exposure.
Putting this into context, every hour spent in one of these areas would result in a radiation dose of approximately 1.5 uSv, equivalent to around 15 minutes in an airplane or .05% of our annual background radiation exposure. However, the areas identified with slightly heightened radon levels are used sporadically for no more than 1 - 2 hours a week maximum so duration of exposure is extremely low.
What will the University do to protect staff?
To protect its staff and students, the University, will take the following action for all areas identified as exceeding the action level:
Inform the HSE Specialist Inspector.
Seek advice from the HPA and consult with the Universities Radiation Protection Adviser on the action that should be taken eg increased ventilation, restricted access.
Increase the ventilation to reduce radon levels or restrict access to reduce exposure time.
Provide information to those staff and students affected.
Undertake further monitoring as required.
In addition, the University has prepared the Radon Policy Standard (see above) that outlines the roles and responsibilities of Colleges / Departments and specific University individuals.
For further information on radon please contact Health and Safety Services.