Seventy-two individuals tragically lost their lives because of the horrific conditions of the Grenfell Tower fire in the early hours of June 14, 2016. The subsequent Hackitt Review pulls no punches. It concludes that there is a fundamental need for change in attitudes to fire safety. Life safety, says Government Minister the Hon James Brokenshire MP, must now be paramount. And that means paying more attention to the products and technologies that are used to provide resilience against fire.
The Grenfell Tower fire catastrophe has shaken the world of construction, design and fire safety. Such a fire was not anticipated. If it had been then so many would not have died in such horrific conditions – extremely intense fire spreading so easily from inside to outside then breaking back in at several levels, apparently from all sides, at height, followed by extreme dense smoke development and further fast fire spread within the building through what fire-retaining walls were in place.
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A key principle of fire safety design is called compartmentation – i.e. constructions to contain fire where it breaks out, and prevent its spread using designated fire-resistant constructions that are able to resist fire penetration from one side. Compartmentation evidently failed in Grenfell.
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The essence of compartmentation is to contain fire, to stop physical fire movement by using fire-proof barriers – to minimise the risk, for as long as possible and as effectively as possible.
Fire isolation and separation from those trying to escape is crucial.
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Firefighters need to be able to get into the building with minimal risk, to carry out their rescue and firefighting roles. Sprinklers systems for suppression during the early stages of fire need to work in the place where the fire breaks out before they can be perhaps overwhelmed by fast fire spread.
A lesson from Grenfell should be how fast fire can grow and spread given the fire load from fixtures, fittings, furnishings and constructions in today’s residential environment. The key fire safety strategy of stay-put that has been such a focus in Phase 1 of the Grenfell Inquiry, under Judge Sir Martin Moore-Blick, critically depends on compartmentation and fire separation working reliably and dependably.
Most materials deteriorate in fire, some more catastrophically than others. Standard glass, for example, has no significant ability to resist fire: it is notoriously susceptible to failure due to thermal shock, easily cracks and can fall apart under even quite mild thermal stress. Even specifically developed fire-resistant glass types have their failure mechanisms. And their resilience is limited, as exemplified by standard test classifications which are typically just for 30 minutes or perhaps 1 hour, (with more sophisticated constructions needed for 90 minutes and longer, perhaps to 2 hours).
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FireLite ceramic glass is a different material compared with standard flat glass compositions.
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Ceramic is an engineered material designed to be resistant to thermal shock and thermal stress.
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It has a very high softening and flow temperature compared with standard glass types, much higher than temperatures likely to occur in typical building fires.
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Most importantly, FireLite ceramic is able to survive in one piece, untouched, under a water stream from sprinklers or firefighter hoses on the hot ceramic. Tests have conclusively demonstrated that.
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FireLite – only 5mm thick – has been tested several times for resilience under standard test furnace conditions for longer than 4 hours, remaining unchanged and still in place, in one piece.
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If extended time is required in holding fire back then ceramic is a real option to consider.