Jane Embury looks at the role of advanced glazing in airport design. Wrightstyle has supplied to a number of airports including London Luton, Gatwick and Heathrow and, internationally, Doha, Dubai and Taiwan.
Wrightstyle, the advanced glazing system specialist, has conducted a milestone fire test of particular significance for safety in airports.
Specifications for fire-rated glazing systems generally assume that a fire will only spread from a high-risk area. The specification only therefore requires protection in one direction.
But that ignores the fact that a fire can start on either side of a fire-rated glazing system. It’s an issue that Wrightstyle has successfully addressed.
The test, with the exterior building surface facing into the furnace, delivered 148 minutes of integrity and insulation. Most importantly, that fire protection is dual directional.
The Wrightstyle system, complete and guaranteed, is a significant safety advance for a sector that is vital for economic recovery.
While we tend to think of the airline industry as being largely about commercial travel, last year there were 16.4 million flights – many carrying cargo.
Airports’ economic importance also make them a terrorist target, and not only to major airports. The 2007 attack at Glasgow airport underlines how terrorism can be both national or local.
The 2013 fire at Nairobi’s Jomo Kenyatta airport, the busiest in East Africa, underlines the economic importance of airports.
The airport is of major economic importance for the country, both for tourism and exports. The fire, was most probably started by faulty wiring.
Remarkably, while there was extensive damage to the airport, there were no casualties. It was, however, a major economic blow to the country.
The Nairobi-based Inter-Region Economic Network said that it disrupted 16,000 passengers and 200 flights a day. The impact was felt in Kenya and across the entire region.
Countering threats starts with a comprehensive assessment of the possible risks the airport might face. Modern building safety is largely determined by a multi-disciplinary approach to assessing hazards. Those also include, for example, power failure and cyber-attack.
For an airport, other factors might have to be considered – from the kinds of threat specific to that country or region, to the airlines that make use of the facility.
There are a number of assessment methodologies to understand the potential threats, identify the assets to be protected, and how best to mitigate against those risks.
That assessment then guides the design team in determining acceptable risks and the cost-effectiveness of the measures proposed, both airside and landside.
The UK has been at the forefront of airport safety, largely because of the historical threats posed by Irish terrorists. Terrorists fired mortar bombs onto the runway at London Heathrow in 1994.
While they failed to detonate it underlines how threats can come in different directions, and requires a dual-directional approach.
The airport designer’s conundrum is to build a facility able to safely handle large numbers of people, while making their experience as hassle-free as possible.
Since 1996, the UK’s Department for Transport has published guidance in the form of Aviation Security in Airport Development (ASIAD).
The guidance covers many of an airport’s critical functions, from security checks on passengers to aircraft hold baggage. It also covers the location of car parks and the glazed elements in the building’s design.
Importantly, it provides guidance on areas immediately outside terminal buildings to create an exclusion zone for unauthorized vehicles.
Stand-off distance is an important consideration. A bomb detonating at seven metres from the terminal façade can generate blast pressure of up to one ton per square foot.
However, at 30 metres, blast pressure falls to one-tenth of a ton per square foot. That’s well within building regulation parameters on structural integrity.
Modern building design, in airports as elsewhere, now makes extensive use of glass. It brings in ambient light and creates a more pleasant interior environment.
The extensive use of glass has come about as a result of investment in innovation, both to develop new laminated glass types and framing systems able to withstand blast pressure.
At Wrightstyle, we have gone beyond computational assessment to also conduct live bomb testing. One test involved a simulated lorry bomb attack (500 kg of TNT-equivalent explosive) detonated 75 metres from the test rig.
It was followed by a simulated car bomb attack on the same glazing system (100 kg of explosive). This was detonated at a distance of 20 metres, and both tests were equally successful.
Our compatible systems, with the glass and steel framing systems tested together, are accredited to EU, US and Asia Pacific standards.
Our strong advice is to always specify the glass and framing as one unit: in a real fire or terrorist situation, the glass will only be as protective as its frame, and vice versa.
Fire and terrorist attack are potent threats to be assessed, comprehensively guarded against, and with regular rehearsals to ensure that response teams can deal adequately with any emergency.
That multi-dimensional approach also extends across the built environment. Or role is to develop next-generation products and systems to ensure new levels of fire and terrorist protection.
Airports will soon be busy again, and now is the time to plan for a safe return to normality.