Most people go through their lives without thinking about radon. This noble gas is invisible, it has no smell, and you would not notice it in a room. But did you know that, each year, it’s estimated to cause 1,100 deaths across the UK? For context, this is equivalent to about two-thirds of the number of people killed on roads in Great Britain during 2025.

With growing awareness around this silent killer, and increased regulatory scrutiny, housing providers are coming under increasing pressure to have a strategy in place for managing radon. In this article, we’ll explore the dangers of radon, the strategies that housing providers are using to manage it, and the regulatory drivers that they need to be aware of.

An Invisible Killer

Radon is a radioactive gas that occurs naturally in the ground. It’s produced as small amounts of uranium naturally decay in bedrock, especially granite or shale. Because of this, radon levels vary greatly across the country. Housing providers can get a rough view of how much radon is at a property using UKHSA’s radon map or order a survey for more details.

Radon naturally accumulates in homes, especially in winter months when rising air from heating draws it out of the ground and closed windows keep it trapped indoors. You won’t immediately notice high concentrations of radon, but over time they can increase the risk of lung cancer. In fact, Cancer Research UK estimates that 5% of lung cancers in the UK are linked to exposure to radon. This risk is significantly higher for people who smoke.

The average radon level in UK homes is around 20 Bq/m³ (Becquerels per cubic metre). The UKHSA has set out an Action Level of 200 Bq/m³, above which it recommends that radon levels at a property should be reduced. It also sets out a Target Level of 100 Bq/m³ for remediation and preventative work. If radon levels are below the Action Level but above the Target Level, remediation should be considered.

How Housing Providers are Managing Radon

As radon is invisible and odourless, detection and monitoring systems are needed to check radon levels against these thresholds. There are two common ways of doing this. The first is the use of single-use radon detectors. These can be installed in homes in areas identified as being at high risk from radon, left for three months, then removed and sent to a certified lab for testing. This provides an accurate reading of average radon levels at a property over this period.

Another option is a continuous radon monitor, which can be installed at a property and gives continuous readings over time. These readings can then be used to determine the average level of radon at a property.  This reduces the need for contractor visits and multiple single-use detector and gives increased visibility of seasonal changes. As a result, they are seeing increased adoption in the UK and across the globe.

However, when using a continuous radon monitor, housing providers should be careful about which sensors they use. Consumer-grade systems may not always provide the detail, reliability and accuracy of higher-end sensors.

Where a landlord identifies a high level of radon at a property, they then need to take the necessary measures to reduce it. The most common option is a radon sump, a system that uses a fan to extract radon from under the building, but other forms of ventilation are also sometimes used.

Looking Towards Awaab’s Law

Radon falls within the Radiation hazard under the HHSRS (Housing Health and Safety Rating System). Because of this, it will be covered by Phase 3 of Awaab’s Law in England. This is currently expected to come into force in 2027.

Awaab’s Law requires that social landlords investigate and repair hazards which fall under the regulation within tight timeframes. Phase 1 of this regulation currently covers damp and mould, as well as emergency hazards, and many housing providers have faced a very large number of disrepair cases since the regulation came into force, which has put significant strain on their resources.

Many social landlords are now using environmental monitoring systems like Aico’s HomeLINK technology to identify high-risk properties and carry out preemptive maintenance during summer in order to reduce the strain during winter.

While radon is not as immediately apparent as damp and mould, information on risk levels is publicly available and consumer air quality sensors are increasingly common in the UK. A robust, proactive way to identify high-risk properties will be crucial going forward.

There is also the question of how to monitor the effectiveness of any interventions at the property. Awaab’s Law requires that housing providers take the necessary steps to make the property safe and prevent recurrence, which means demonstrating that these measures have been effective. This typically means retesting properties with a separate single-use detector after they have installed a sump.

The Benefits of Continuous Monitoring

As the way that housing providers manage radon continues to evolve, continuous monitoring looks to provide a valuable complement to traditional testing methods. Rather than providing a snapshot of radon levels over a fixed testing period, continuous monitors can provide greater visibility of how levels change over time, including the impact of seasonal and environmental factors.

For social housing providers, this additional insight could help identify properties that may require further investigation, support more informed decisions around remediation, and provide an ongoing way to assess whether interventions have been effective. For example, where mitigation measures such as a radon sump have been installed, continuous monitoring can help landlords track changes in radon levels over time and understand whether the intervention is having the intended benefit at the property.

Continuous monitoring can also reduce the need for repeated contractor visits and the installation and removal of multiple single-use detectors, helping housing providers take a more proactive approach to managing radon across their housing stock.

With increasing awareness of the risks associated with radon and greater regulatory focus on how housing providers identify and manage hazards, having reliable and accurate information about radon levels will become increasingly important.

Continuous monitoring has the potential to play an important role in helping landlords move from periodic testing towards a more informed, proactive approach to radon management.

News – Aico