Explosive stuff

“Did I mention that we’re working in £$!kb* Ooh, I’m not sure if we can talk about that. I’d better check before you write it down.”

Talking about his work is a frustrating exercise for Chris Bowes. The man who heads up TPS Consult’s counter-terrorism division flicks furtively through a thick presentation holding examples of his team’s work. “I can’t show you that, I’m afraid. Or that. I can show you that, but you mustn’t mention the client.”

That’s one of the problems when you’re in the business of designing buildings to be terror-resistant. TPS’s clients such as the Ministry of Defence and the City’s top financial institutions don’t want details of their buildings to go public.

What Bowes can reveal is that business is booming, if you’ll excuse the expression. He’s had to take on two more members of staff in the past two years, boosting numbers to 16. September 11th 2001, when New York’s twin towers fell, opened new doors for Bowes’ expertise. “Until three years ago the majority of our work was UK-based: the Irish problem. Now it’s perceived to be much more of an international problem. We are working on government buildings and financial institutions around the world.”

Bowes is particularly proud of the fact he has won a contract to design the cladding for the new building ,which will take the Twin Towers’ former plot. The US market is hard to crack because “the Americans think they can do it all.”

Becoming the best

So how do you become an expert in explosion engineering? Bowes, a civil engineer like all of his staff, started in 1993 designing bunkers for the military which could resist bombs. He worked for the government’s design body, Property Services Agency (PSA), until 1992 when a Tarmac/ Black & Veatch joint venture bought it. Tarmac – now Carillion – took full ownership two years later and it became Tarmac Professional Services (TPS). About half of Bowes’ team remain from the PSA days.

The team has unique expertise, says Bowes. “We believe we are the best”. It works closely with the MoD and has been in some term commissions for 12 years. It also has a wealth of data gathered over 40 years.

The workload began to shift from the late 1980s as IRA bombs went off around the UK. People started to ask for their buildings to be blast-resistant which meant the TPS designers had to gain expertise in glass rather than concrete. (Never say ‘blast-proof’, by the way, “because you can always build a bigger bomb,” he says.)

The easiest way for TPS to work is to be involved in a building’s design from day one. Otherwise things can get expensive. For example, when TPS was brought in part-way through the design of a multi-storey financial building in the city, it found that the main computer room was on the first floor. A schoolboy error in explosion engineering terms, apparently. Put it a few floors from the top of the building so it’s a long way away from ground-level vehicle bombs. Otherwise you have to put ultra-thick walls around the room.

The designers may use hand calculations or computer models to work out how a building will behave in the case of an explosion. Occasionally, they even get to blow up mock-ups. “That’s where it gets exciting,” says Bowes, “and also a bit terrifying because you have to prove that your calculation is correct.”

But aren’t bombs a bit old-hat now? The risk of chemical attack and germ warfare are constantly in the news. That possibility has been around since 1995 when there was an incident on the tube in Japan, says Bowes, but it’s still quite difficult to carry out a chemical attack. TPS could design a building to be resistant to such an attack but the extra M&E expenditure could double the cost of a building. Making it blast resistant adds around 3.5% to the cost.

However, there are buildings where chemical attacks are being looked at, says Bowes. Which buildings, then? “Er, I’m afraid I can’t say.”