Respiratory radon hazards

Achieving workplace statutory compliance

Radon, a radioactive by-product of Radium, is known to be the second largest cause of lung cancer1 and the third leading cause of premature deaths in the UK2. While awareness is building on the potential health implications of long-term exposure to the natural gas, more could be done to ensure employers have an adequate and appropriate strategy in place to protect employees and achieve workplace statutory compliance. This article explains the risks of radon and looks at how to manage and mitigate exposure to radon in the workplace effectively.

Radon and its risks

Radon is a colourless, odourless and tasteless radioactive gas that is formed during the decay process of Uranium. Radon decays to produce a series of by-products, including Polonium, which emits radioactive ‘alpha particles’. These are particularly dangerous to humans when inhaled, as they damage the lung cells – this damage is linked to mutations and cancers. The risk is also greater for smokers, as their lungs are more susceptible to damage.

Radon is measured in Becquerels (Bq) per cubic metre of air (M3)3 and the recommended exposure limit in the workplace is 400Bq/M3 (with a lower limit of 200Bq/M3 in the home)4. However, it’s important to note that the World Health Organization is campaigning for the workplace limit to be lowered to 300Bq/M35.

Managing radon exposure is crucial when considering the potential levels of radiation people may come across, even in their day-to-day lives. Based on current measurements, radon exposure is estimated to account for around 50 per cent of the average person in the UK’s annual personal radiation dose (although this may vary depending on the area within the UK, as some locations are more affected by radon than others). It’s also estimated that a significant proportion of an employee’s daily exposure to radon may occur in the workplace. It’s therefore essential that people are aware of the radon levels in their home or place of work, as it’s estimated the risks of living in a home with a radon measurement of 200Bq/M3 can be significantly worse for your health than working in a nuclear fuel plant, for example. Put another way, prolonged exposure (eight hours per day) to radon levels of 200Bq/M3 (the current allowed home limit) is the equivalent of having more than five cigarettes a day or 112 x-rays per year.6

Who is affected by radon?

Every building contains radon but the levels are usually low. The chances of a higher level depend on the type of ground and the location. All workplaces including factories, offices and shops can be affected but basements and poorly ventilated ground floor rooms are more at risk, as radon is more likely to enter a building from the ground. In densely populated areas, the risk can also be greater, as there is more demand for office space and these lower ground rooms are more likely to be occupied.

Worker protection

By now we are aware that personal protective equipment (PPE) is not the ‘go to’ for keeping workers safe, but rather the very last protective measure that can be put in place for those situations where the previous hierarchies of control have failed to sufficiently protect the worker.

While respiratory protection is often used as the last line of defence in many environments, it’s not always appropriate. In terms of radon, for example, respiratory protection is not an adequate control measure and instead it is recommended to limit and monitor exposure times in affected areas or reduce radon levels by methods of mechanical remediation. That said, inhaling dust contaminated with radon can expose you to radon particles so in case of exposure to a radon containing atmosphere it’s worth being protected.

Radon gas breaks down into radioactive particles that can get trapped in your lungs when you breathe. As they break down further, these particles release small bursts of energy. This can damage lung tissue and lead to lung cancer over the course of your lifetime. The primary cause of lung cancer among non-smokers is exposure to radon, and the particles from its decay. Overall, radon is the second leading cause of lung cancer. Radon is responsible for about 21,000 lung cancer deaths every year. About 2,900 of these deaths occur among people who have never smoked. Radon exposure also increases the risk of lung cancer and death for workers.

Workplace statutory compliance

Under the Health and Safety at Work Act 1974, employers must, so far as is reasonably practical, ensure the health and safety of employees and others who have access to their work environment. Alongside this general guidance, to ensure workplace compliance, employees must meet two statutory health and safety obligations that are linked to radon. The Management of Health and Safety at Work Regulations 1999 requires the assessment of health and safety risks, which should feature radon and the Ionising Radiations Regulations (IRR99), which includes guidance on monitoring exposure in radon affected workplaces.

Under these regulations, all workplaces should carry out a radon risk assessment if they meet the following criteria:

  • All below ground workplaces in the UK (that are occupied greater than an average of an hour per week or 52 hours per year)
  • All workplaces in radon affected areas (1-30%) by geographical assessment (as per Public Health England’s UK radon heat map7)

Depending on the potential level of risk, properties will need to be assessed for radon levels on a regular basis as part of an ongoing mitigation strategy.

Managing and mitigating exposure

It’s recommended that radon risk assessments are carried out in all below ground workplaces in the UK and all workplaces located in radon ‘hot spot’ areas. Particularly at risk areas are classified as locations identified within the 1-30% category by geographical assessment – you can check your area by using the interactive maps tool on the UK Radon website (

It’s crucial that employers are aware of the risks of radon and methods of managing and mitigating exposure. Thankfully, it’s simple and cost-effective to measure radon levels and relatively straightforward to manage and mitigate the risks.

Measuring radon

Businesses investigating radon issues are recommended to install specialist radon detectors or digital monitors for a three-month test period, in order to establish average radon levels. Rather than a standalone test, it’s advised that measuring radon levels is part of a wider risk management strategy to investigate and treat radon issues. This will often include radon risk assessments (including a geographical, architecture and workplace assessments), occupational exposure advice, the deployment of a remediation strategy and the recommendation and project management of any remedial contractors that may be required to install any engineered solutions to reduce exposure levels.

In some circumstances for radon remediation in existing buildings, engineered systems are required to modify the pressure configurations and airflow to effectively lower reported levels. A radon ‘sump’ can be installed under a building to collect radon particles and redistribute outdoors via a connecting pipe. Depending on the radon levels involved, a radon sump can either be active (with a fan) or passive (without a fan). It’s important in these instances that a system is in place to ensure any mechanical systems stay operational and remain switched on. It’s crucial that employers communicate a radon remediation strategy with all employees to ensure they are aware of the measures put in place and to encourage compliance and, ultimately, the success of the programme.

Exceeding workplace limits

A more active remediation programme is required when radon levels exceed the recommended workplace limit of 400Bq/M3. The Health and Safety Executive (HSE) sets out a five-point mandatory requirement for these circumstances:

  1. Immediately limit exposure by risk assessment and control area access.
  2. Workplace controlled area determined by a Radiation Protection Advisor (RPA).
  3. Plan and implement work to reduce radon exposure levels to below 400Bq/M3.
  4. Inform employees about the nature and level of risk.
  5. Inform HSE (Local Environmental Health Officer) of results and subsequent plans.

Public Health England also recommends in this scenario to arrange additional testing and monitoring, with radon measurements recorded every two months until the radon levels are reduced to acceptable levels.

Achieving safety

The following best practice case study addresses how to achieve a safer workplace through effective radon management.

Typically, older buildings and buildings with a unique architecture report higher radon levels, as businesses occupying these types of dwellings tend to utilise below ground rooms such as vaults, strong rooms, book rooms and utility service ducts more frequently. This is particularly relevant in banking or retail environments, where another common challenge is the fact that the companies involved are often responsible for managing a large portfolio of properties in different locations, with varied potential risks and requirements.

In response to these challenges and due to a lack of confidence in its previous consultant, a global financial institution called on Bureau Veritas to implement a formal radon management system that was tailored to its portfolio and requirements. The subsequent partnership approach adopted by Bureau Veritas and the rollout of the recommended strategy resulted in significant cost savings on mechanical remediation solutions, as well as on maintenance and upkeep, and also enabled the client to utilise space at their premises more efficiently by managing the risks associated with radon exposure.

The programme of radon inspection and certification, undertaken over a 12-month period, provided a scientific, risk-based and targeted approach to enable the client to focus the correct level of investment in areas where real radon risks exist in the workplace. Each branch was risk-assessed and the resulting data gathered was added to a robust database that, moving forward, can be used to assess the effectiveness of remediation measures in place and the viability of branches.

Following the first year of consultancy, Bureau Veritas achieved cost savings of more than £1million, compared to the client’s historical spend on previous physical remediation, with an estimated 40-60 per cent additional projected savings above and beyond this figure over subsequent years. Much more than financial savings however, the approach has meant that the client has gained confidence in achieving regulatory compliance and in ensuring the safety of staff and others using affected areas.

The radon assessment and management strategy was part of a single source solution for all Health and Safety compliance-related services provided by Bureau Veritas; offering efficient and effective support to more than 900 branches across the UK for this particular client. The approach has been so successful that the client is now planning to roll out the strategy to its operations in other regions worldwide.


Radon levels are easier to monitor during the winter months and, as such, it’s an ideal time for businesses to consider assessing the risk in the workplace and appropriate remediation solutions.

It’s important to remember that radon levels can vary and need to be regularly assessed depending on the results of an individual risk assessment – recommendations vary significantly from repeat assessments every two months for workplaces currently exceeding exposure limits to every 10 years for lower risk environments. It’s common for the majority of workplaces to be assessed every year.