FPA research into toxicity of building cladding released
THE RESEARCH from the Fire Protection Association (FPA) has seen it call on the government to ‘consider the role that toxicity should play in product approvals’ ahead of the expected combustible materials ban.
This new research, available online here, has seen the FPA investigate the effects of toxic fumes generated by ‘certain cladding combinations’ in designs ‘still permitted’ by building regulations, as well as the effect that this has on those occupying buildings in a fire. The FPA has called on the government to ‘consider the role that toxicity should play in product approvals’ before it makes a final decision on the combustible materials to be banned.
In addition, the FPA stated that the report’s ‘initial research’ could ‘assist the government’s decision on the future use of combustible materials in the construction of buildings’, with a key feature of rainscreen cladding the space formed between insulation and cladding panels. This may contain other materials including vapour membranes to keep out moisture, and ‘strict rules govern’ how internal walls must contain fire, but ‘the same is not true of the external walls’.
Here, there are ‘few requirements to prevent the spread of flame and heat from outside’, and devices or features such as bathroom and kitchen vents ‘have the potential to transmit fire and smoke’ from the cladding into the occupied space. The FPA report confirms the ‘potential for serious harm’ to any person exposed to such toxic products in a fire, looking at a typical living room in a building covered in cladding.
Findings of the test here suggested that for some of the compliant combinations of material, once a fire breaks into cladding containing a vent connected to an apartment, those inside are ‘predicted to lose consciousness within 10 minutes’, and unless rescued ‘would die within 30 minutes’. The FPA testing, undertaken at its laboratory in Blockley, Gloucestershire, was funded by the UK insurance industry through RISCAuthority, and was assisted by Arup and the University of Central Lancashire.
This testing involved a selection of combinations of cladding and insulation ‘legitimately used’ on UK buildings, including similar combinations to those used on Grenfell Tower. Four tests were conducted over four months that compared the potential contribution from smoke toxicity that could be made by the differing configurations.
The research has been offered to both the government and the Grenfell inquiry by the FPA to ‘assist in future discussions on the merits of the specification of non-combustible materials in buildings’, as well as the ‘need to strengthen regulations in respect of fire and smoke ingress’. The FPA added that ‘at the very least’ the research should ‘prompt further research into whether the evaluation of fire toxicity should become an integral part of the building products approval process’.
Dr Jim Glockling, the FPA’s technical director, commented: ‘Measuring smoke toxicity in building products is currently not a legal requirement. The results of our study show that current regulations may not adequately protect occupants from the potentially toxic fire gases from materials burning on the outside of buildings. Some current common cladding material combinations were shown to present less of a threat than others. There is certainly a need for further study.’
Jonathan O’Neill, FPA managing director, added: ‘This work reinforces our view that a range of factors, such as measurement of toxic fumes, need to be considered when choosing building materials, in order to protect buildings and ultimately save lives. The [FPA] wants assurance from government that systems are in place to regularly review building standards to ensure that the UK can never experience a tragedy on the scale we witnessed at Grenfell – on our or any future generations’ watch.’