Certification of doorsets to include smoke control
The tragic fire at the Grenfell Tower in June 2017 has led to much examination of the escape protocols for high rise buildings and the materials and products utilised with the build process. In this blog, in support of Fire Door Safety Week, Secured by Design Technical Manager Alfie hosker discusses the certification of doorsets to include smoke control.
Post Grenfell, the government quite rightly called for further investigations and Secured by Design (SBD) took an active part as a member of the Grenfell Technical Group, which was set up in March 2018 to provide technical advice specifically on entrance doorsets to individual flats - which includes the door, associated frame and all component parts, such as the glazing and door hardware.
The Group, which included other not-for-profit organisations including the Fire Industry Association (FIA) and the Door and Hardware Federation (DHF), met frequently throughout the rest of that year. Our comprehensive technical findings were duly reported to government via the Grenfell Independent Expert Panel.
Building on the collective expertise and experience within SBD, FIA and DHF the three organisations took the unprecedented step of collaborating on a document entitled ‘Guide For Selecting Flat Entrance Doorsets’ which we published in March 2019 https://www.securedbydesign.com/images/downloads/DOORSET_BROCHURE_update_25.3.19.pdf
Following a further internal review of our requirements, we have revisited the possible life-threatening characteristics of fire rated doorsets. As a consequence of further consultation, we now understand more clearly the importance of asphyxiation caused by smoke inhalation and that being the most common cause of deaths in flats when a fire occurs.
Therefore, with effect from 1st June 2022 we will require all SBD member companies with doorsets listed with us that are fire rated and that are required by UK Building Regulations (England, Scotland, Wales and Northern Ireland) to have smoke control properties for the intended installation e.g. flat entrance doorset, to be certificated for the following attributes – Security, Fire and Smoke Control.
Currently doorset thresholds can legitimately be tested to BS 476-31.1 or BS EN 1634-3 with the threshold taped up, and be assigned an ‘S’ designation (according to the guidance within Approved Document B) or an ‘Sa’ classification (when classified according to EN 13501-2), as the threshold gap is effectively discounted in both instances. It is also possible to maintain designated smoke performances (i.e. S or Sa) when following the guidance given in BS 8214, which allows for a 3mm gap at the threshold in situations where fitting a threshold seal is not practicable.
In our opinion neither are acceptable in a ‘real world’ fire scenario, the former (taping up the threshold) proves nothing when the doorset is exposed to smoke in an apartment block and could therefore lead to smoke unnecessarily entering an area designed to be a safe haven, and the later (the 3 mm gap allowance) has been independently proven to allow smoke leakage of up to 10.5m3/h/m – three times the allowance of 3m3/h/m in the current Building Regulations. You can find out more about this series of tests commissioned by the Intumescent Fire Seals Association (IFSA) here: https://www.ifsa.org.uk/wp-content/uploads/2021/04/IFSA-Fact-Sheet-02-v0321.pdf
SBD has committed to promoting our requirements and to support other organisations lobbying for change in this important area. Quite simply we are adamant that any doorset that carries our approval should be fit for purpose in all declared characteristics, but especially those that are life critical such as fire, security and smoke control. We are committed to saving lives and making homes safer places in which to live, work and play.
Alfie Hosker is the Technical Manager at Secured by Design.
Alfie joined SBD in 2014 after serving over 20 years in the UK Police Service across a number of disciplines including CID, Stolen Vehicle Squad, Public Order, Neighbourhood Policing, Licensing and Crime Prevention.
He also spent a number of years within the various Planning, Highways and Building Control Departments advising on Designing Out Crime, Counter Terrorism, enforcement, planning policy & applications.
Alfie Studied at Leeds University and later at Oxford Brookes University in the field of Crime Prevention. He is also a qualified teacher.