Cleaner Air for Scotland 2 progress report (2023/24) explained

The Scottish Government recently published their Cleaner Air for Scotland 2 (CAFS2) progress report for 2023/24. The HETAS team have summarised the report and the progress that has been made since last year.
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The Scottish Government recently published their Cleaner Air for Scotland 2 (CAFS2) progress report for 2023/24, providing updates and intentions for the future. The progress report details actions across ten areas that build the policy framework for air quality in Scotland up to 2026, summarising progress since the 2022/23 progress report. 

The progress report directly relates to our industry through three sections in annex C. Relating to biomass and domestic burning, the progress report signals that research is due to be complete in 2026 and discussions are currently ongoing, but little has yet changed since the previous progress report. There are plans for additional measures to be put in place to help minimise air pollution from domestic and biomass burning.  

HETAS works closely with all UK governments and devolved administrations, providing factual advice and valuable data to inform policy decisions. Our organisation and its registrants plus certificated scheme members are regarded as vital to influencing a cleaner, safer, and more sustainable future for domestic and non-domestic burning. 

Actions, milestones, and updates

Biomass and domestic burning are discussed across the following sections in annex C: 

‘Tackling non transport emissions (short term action) 

CAFS2 Action: the Scottish Government proposed to commission research undertaking source apportionment to discover the proportion of particulate matter emissions and other key pollutants attributable to domestic burning, whilst also examining the geographics and demographics. 

2023 Milestone(s): Scotland’s Rural College are leading a research project exploring urban air pollution issues, with a particular focus on domestic combustion, the fuel used, and the geographic distribution to examine the effects on particulate matter and human health. 

Update: research is underway, and two field sampling campaigns have been completed thus far – the five-year project is due to be completed in 2026. 


‘Tackling non transport emissions (medium term action)’ 

CAFS2 Action: Scottish Government and local authorities will consider changes to the development rights for flues for wood-burning stoves and biomass boilers. 

2023 Milestone(s): the third phase of review was consulted between May and August 2023.  

Update: further work is underway looking at geographically targeted approaches that could address issues. 


‘Tackling non transport emissions (long term action)’ 

CAFS2 Action: investigation into potential measures to control the supply of the most polluting domestic fuels – banning house coal, prohibiting the sale of certain types of wet wood, restricting the sulphur content of smokeless fuels to 2%, and introducing a minimum renewables content for manufactured smokeless fuels. Any of these measures would be implemented over a transitional period to allow businesses to adapt to new requirements. 

2023 Milestone(s): an evidence report to inform proposals regarding banning the sale of house coal and high sulphur content MSF has been published. 

Update: discussions are being held with the Domestic Emissions Working Group. 


The progress report also provides milestones and updates on other relevant outstanding actions in annex C, such as: 

‘Health (long term action)’ 

CAFS2 Action: with support from Public Health Scotland, the Scottish Government will commission an assessment to understand how a representative sample of the Scottish population are exposed to air pollutants during realistic activities over a normal time period. 

2023 Milestone(s): research will be commissioned by the end of 2024. 

2024 Update: an evidence review has been commissioned to identify realistic assessments of air pollutant exposure. Following the completion of this review, the next steps will be considered. 


‘Behaviour change (medium term action)’ 

CAFS2 Action: a public engagement strategy on air quality will be developed. 

2023 Milestone(s): the Scottish Government are aiming to publish the framework in 2024. 

2024 Update: three public engagement workshops have been hosted and the ‘Key behaviours for air quality’ report has been published. 


‘Tackling non transport emissions (medium term action)’ 

CAFS2 Action: a revision of the Clean Air Act 1993 will be considered following discussions with local government and Scottish Environment Protection Agency (SEPA). 

2023 Milestone(s): the Clean Air Act 1993 will be reviewed with local authorities and SEPA in 2024. 

2024 Update: initial conversations have taken place to review the Clean Air Act 1993 and next steps are being considered. 


‘Further progress review (long term action)’ 

CAFS2 Action: a review the implementation progress of CAFS2 during 2024 will be initiated, with a further version of Scotland’s air quality strategy aiming to be in place by the end of 2025. 

2023 Milestone(s): a timeline will be developed and published in the next progress report. 

2024 Update: the development approach for the next phase in air quality has been agreed and work will begin in Summer 2025. 


There are also other topics discussed in the report, with annex A detailing ‘completed actions’ and annex B detailing ‘completing ongoing actions’. Transportation and industrial emissions are two other topics explored in the progress report – further information on these topics, and others, can be found in the Scottish Government’s full progress report for CAFS2. 

Minimal developments

The 2023/24 progress report suggests there has been a lack of immediate action and minimal progress since the 2022/23 report. It is positive to see extensive research undertaken and its completion in 2026 will provide valuable information regarding the geographical and demographic variables surrounding air pollutants in Scotland, enhancing global studies of source apportionment. We await an update on the ‘potential measures to control the supply of the most polluting domestic fuels’ from CAFS2. 

Recent uncertainties surrounding the Scottish New Build Heat Standard 2024 have exhibited the need for clear, informed action from the Scottish Government where Scottish stove users and air quality are carefully considered. Discussions regarding the sale of wet wood and house coal, for example, need to turn into actions. This will reduce the emissions resulting from domestic combustion and help to inform consumer burning habits, promoting responsible burning. 

HETAS recommend that Scottish Government further its policy encompassing domestic fuel use, prohibiting the sale of wet wood, banning the sale of house coal, and restricting the sulphur content of smokeless fuels to 2%, aligning with current legislation in England. These actions would reduce domestic combustion emissions across Scotland. 

Bruce Allen, CEO of HETAS, commented: 

We have seen the success of the current policies in England. Prohibiting the sale of wet wood in volumes under 2m³, banning house coal, and requiring the sulphur content of smokeless fuels to be lower than 2% were provisions included in ‘The Air Quality (Domestic Solid Fuels Standards) (England) Regulations 2020’, and its implementation has been well-received. These provisions, among others, were implemented over a transitional period, allowing businesses to adapt and have their circumstances considered.

“The Ready to Burn scheme, administered by Woodsure (for wood fuel), has greatly assisted improving air quality by reducing the harmful emissions – such as particulate matter – from domestic burning. By helping people choose the right fuels with Ready to Burn certification, educating consumers on responsible burning habits, and legislating the prohibition of highly pollutant fuels, we can work towards a cleaner, safer, and more sustainable future.


Efforts by manufacturers to improve combustion in appliances sold across the UK have aided in the reduction of emissions resulting from domestic burning, with Cleaner Choice appliances going above and beyond the requirements to further minimise particulate matter emissions. It is important that we continue working to minimise emissions. Scottish legislation aligning with the legislation currently in place in England would be a step forward and an actionable approach to improve air quality across Scotland. 

HETAS will continue its work to minimise emissions for a cleaner, safer environment and we are on hand to offer support to all UK governments and devolved administrations. We have experience administering government schemes and we will continue to use our unique position to provide trusted, factual advice, informing policy decisions. 

For the latest news on domestic combustion, government policy, and much more, visit our latest news pages or follow us on social 


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