Adrian McConnell, Head of Charitable Operations, the CO Research Trust

As the weather cools and the heating season gets underway, the media is awash with talk about solid fuel, wood burning stoves and the issues of air pollutants. COP26 shone a light on a range of climate-related challenges including using solid fuels in the home, which has raised awareness of this issue among the growing number of wood burning users.

Open wood burning fire place
Open wood burning fire place

We recognise the issue of indoor air quality as having a significant impact on health, as we’ve talked about recently. However, since we began as a charity one of our main focuses has been on identifying the scale of risk posed by carbon monoxide (CO) exposure.

There are many sources of CO and many ways in which people may be exposed to it. Awareness is still far lower than we would like.

Whilst understanding of the risk of CO exposure has greatly improved in the gas sector, with the requirement to report and have CO alarms fitted, within the solid fuel sector, the risk is still very much unknown. Without the legal obligation to report incidents, we still do not know the extent of CO risk posed by the burning of solid fuels.

Gas cooker
Gas cooker

Our vision is a world where people are not exposed to CO. But you can’t measure what you can’t see. Without sight of the number of solid fuel CO related incidents, we continue to operate in the dark, as we have no idea the scale of the problem, if indeed there is one.

We believe in funding research to help improve this level of visibility, as we believe in providing evidence of safety issues, to help improve health. Without evidence and data, we cannot convince policy makers and others to make improvements to legislation, regulation and procedures to make people safer.

With this in mind, we decided to fund a review of the solid fuel sector and engaged IOM to undertake this. We need to know where the issues are in this sector to establish a way forward that will help improve safety and ultimately reduce risk.

Institute of Occupational Medicine
Institute of Occupational Medicine

As ever, it’s a complicated issue. However, the bottom line is the use of solid fuel burning appliances is increasing, and this may lead to an increase to CO exposure.

We spoke with both lead researcher Dr James Hanlon about his investigation and Bruce Allen, CEO of HETAS, to get their thoughts on the next steps forward.

Dr James Hanlon, IOM

This research project on the landscape of solid fuels and carbon monoxide (CO) was led by myself, Dr James Hanlon along with my colleagues Alice Smith and Ken Dixon at the Institute of Occupational Medicine (IOM) to identify the current state of play for the regulatory and policy landscape and incident data for CO in domestic settings in the UK. The study had the following key objectives:

  • Gain an appreciation of the number of CO poisoning incidents from solid fuels in the UK and the potential levels of under-reporting of incident numbers;
  • Gain an understanding of the barriers to obtain accurate CO incident numbers from solid fuel;
  • Identify the issues or risks associated with the installation, maintenance and use of solid fuel appliances;
  • Identify future research opportunities for solid fuel and CO.

    Solid fuel burning

The methodology used to answer these objectives were a literature review, stakeholder engagement through interviews and requesting and analysing FOI requests to health authorities and the emergency services in the UK. We also compared the current situation for solid fuels with that of the gas sector to gain an understanding of the differences between the solid fuels and gas, and to highlight gaps by performing a gap analysis.

This project also fits into one of the purposes of IOM of controlling hazardous substances to health and making workplaces safer.


The regulatory and policy landscape for the gas sector is seen to be more developed than the landscape for the solid fuel sector in regards to CO. One key difference between the sectors is that of reporting incidents. For gas, there is a requirement incidents under RIDDOR, however there is no equivalent requirement to report incidents for solid fuels to date. There is also need to enforce regulations, communicating regulatory requirements to both stakeholders and homeowners. There are also differences in regulations between the different parts of the UK such as the requirements of CO alarms in homes and building regulations.

It is clear that further work is required for incident numbers for solid fuels and CO. From our study, this data is limited and variable. Publicly available information on incident numbers for solid fuels is limited. For incident numbers for the emergency services, this information is not available from all the Fire and Rescue Services (75% could supply data) in which FOIs were requested. No solid fuel CO data is available from the Police and Ambulance Services. However, from this data it has not been possible to establish if this data is representative as the reporting varies between services. For example, differences include using free text fields for reporting incidents and no CO flags in the reporting systems. It is clear from our review, that the number of solid fuels CO incidents may be underreported.

Future Research

Through our research, we have identified several future opportunities which are important for overcoming the barriers and the potential underreporting solid fuel CO incidents. If we are to advance our understanding of the number of CO poisoning incidents from solid fuels, then the reporting of incidents needs to be consistent across the UK. This could be achieved by developing standardised templates for recording incidents and the development of a centralised database for incidents. Further work is also required on the regulatory and policy landscape, such as improvement (including RIDDOR requirements for solid fuels) and raising awareness of their requirements to stakeholders and consumers.

Bruce Allen, CEO of HETAS

HETAS welcomes the solid fuel and carbon monoxide review undertaken by The Institute of Occupational Medicine (IOM) on behalf of the CO Research Trust.

HETAS Registered Installer logo
HETAS Registered Installer logo

As a not-for-profit organisation the main purpose of HETAS is working together for a cleaner and safer environment. HETAS, and its wholly owned subsidiary, Woodsure support cleaner and safer choices for the use of biomass and other solid fuels, appliances, and associated technologies.

Driving CO safety and the wider issue of indoor air quality is a vitally important issue, and this research is very welcome, I extend my thanks to Dr James Hanlon and his team for their excellent work and to the CO Research Trust for commissioning the work.

As identified in the research, the gas sector and the regulatory and policy landscape is more developed than that for solid fuel. HETAS support cleaner and safer choices for the use of biomass and other solid fuels, appliances, and associated technologies.

This work extends to CO safety, an area that HETAS has supported for many years, leading to provision of the installation of CO alarms in the Building Regulations for new or replacement solid fuel installations back in 2010. HETAS registered installers are well versed on the correct installation of CO alarms.

Data is a key finding from the research and it is clear that reporting of CO incidents at all levels and across the country is not at the level it should be. Our team support authorities in investigation work on solid fuel incidents and are well placed to lead on becoming a central hub for reporting incidents. HETAS created the solid fuel industry ‘Unsafe Situations Procedures’ which has been in place for a number of years, enabling our stakeholders to identify and prevent unsafe situations from occurring.

Improving data collection could save lives
Improving data collection could save lives

HETAS is already taking steps to take forward the key findings from the research and is looking forward to working with the CO Research Trust and other interested parties to bring about further positive change to the solid fuel sector and CO safety.