The Future of Fire Safety in Tall Buildings
Fire safety in tall buildings, and the direction it will take in the future, is a key topic in the fire industry at the moment and one that will be addressed at the 2017 Emergency Services Show, which takes place from the 20th to 21st September in Birmingham.
It isn’t difficult to surmise that the taller a building is, the longer it will take anyone inside to evacuate in the event of a fire.
As buildings have gradually become taller, this has become a key concern for the fire industry as not only does it take longer to evacuate taller buildings, but it can also be harder for fire fighters to tackle a fire quickly and efficiently to prevent the flames from spreading. There are certain regulations that are in place to aid fire fighters, such as the inclusion of dry riser systems, but it is just as important to consider fire safety in the initial construction phases of a building.
Compartmentation is a vital consideration when planning most buildings, unless they are extremely low-rise developments. By breaking a building down into different cells, or compartments, builders can use specific materials that will prevent a fire from spreading from cell to cell for as long as possible.
A common example of this is the use of fire doors, which are prevalent in shared buildings housing a number of different flats. Each flat is considered separately and thick walls and fire resistant liners are also used to ensure any fire would remain enclosed in that space. In taller buildings, more extreme measures should be taken alongside the regular ones.
Fire break floors are a great example of this. Essentially a separate, unoccupied floor; they can help to slow the spread of fire by completely separating occupied parts of a building, other than through a fire resistant stairwell and lift.
The Shard, for example, has plant floors at three different heights throughout its 306 metres, separating the three distinct parts of the building – the hotel, restaurant and offices (1), the private residences (2) and the public viewing areas (3) at the top of the tower. The intention being that if a fire were to break out in one of these spaces it would remain confined to that specific area until a team of fire fighters arrived to subdue it. It also allows each separate area to be considered individually from a fire safety point of view, which means that different regulations can be imposed on each.
Evacuation strategies are another important consideration for tall buildings and this is something that needs to be considered from the point of initial design.
The taller a building is, the longer it will take to execute a full emergency evacuation. The Burj Khalifa in Dubai, for example, stands a staggering 585 metres high, which poses problems for the people at the top of the building in the event of a fire – and it is inevitable that taller buildings will continue to be built.
Although staircases have been a long popular method of evacuation for taller buildings, with people being adamantly warned to avoid the lifts in case they stopped working and trapped anyone inside them, there is only limited space available in stairwells and in large buildings these can quickly become clogged with people trying to get out. In addition to this there should be proper evacuation procedures in place to avoid mass panic in the event of a fire.
Fire alarms should have voice communication systems and there should be a planned escape route and meeting point that everyone is familiar with, although this may be different for different parts of the building.
Following the terrorist attack on the World Trade Centre on the 11th September 2001, a committee was put together to review the building designs and regulatory requirements at that time and make recommendations for change. One thing they did recommend was to make modifications to the stairwell design for taller buildings.
Although fire safety had always been a key concern in the construction of skyscrapers, including multiple means of escape had never been at the forefront as it was then.
New York, of course, lead the way in passing new legislation to incorporate more escape routes and improve fire safety in taller buildings, and in 2009 the International Building Code and International Fire Code, which provides the basis of fire regulations across the US, was updated with huge changes such as including additional stairways, using reinforced lifts to be used in emergencies and creating more space between stairwells and lifts.
It is inevitable that following a disaster, we will strive to make improvements to fire safety in a bid to prevent any future reoccurrence. In the aftermath of the Grenfell Tower fire in London, the founder of the Tall Building Fire Safety Network, Russ Timpson, will speak at the 2017 Emergency Services Show to share information on what should be learned from this tragedy, and the London Ambulance Service NHS Trust will put forward their experience of responding to the incident.
It is inevitable that this will have an impact on the future of fire safety planning in tall buildings, and rightly so. In the immediate aftermath, there were many theories as to why the Grenfell fire occurred, and if anything it is inevitable that the findings in the wake of the tragedy will push for reforms to be made where needed. Although buildings in Britain rely heavily on compartmentation, for example, our rules on sprinkler systems are somewhat more relaxed than in other countries such as the US.
Following the example of Grenfell, where the fire was able to effectively bypass the compartmentation regulations on the inside due to suspected faults in the external cladding of the building, it is fair to say that sprinkler systems should also be considered for high rise buildings as a further method of fire suppression alongside current regulations.