What’s the biggest bomb you’ve defused?
A car bomb that was used to target me in Iraq. The fact that we’d neutralised lots of terrorist devices was making the Shia militias in Basra look foolish. I was told that they “wanted the blond bomb man dead”. They put the bomb outside a hospital, packed with 300 kilos of artillery shells and plastic explosive.

How did you know the car was rigged?
You get a sixth sense. And it was heavily weighted down. Also, witnesses had seen a guy doing something to it then speeding away in another car. We sent in a robot to pop the boot to see what was in there but they had booby-trapped every single opening mechanism, so as soon as the boot opened there was an almighty explosion. It destroyed a million quid’s worth of robot, but we’d moved the patients back and nobody was hurt.

How did you end up in this career?
I joined the Army at 16, then went to Sandhurst when I was 21 and saw a demo of a counter-terrorist bomb disposal. I was mesmerised.

Where on the danger scale would you put the different combat zones?
If the UK is a 1 out of 10, Iraq was a 10. The Balkans was probably a five, Afghanistan a seven, Northern Ireland a five and Colombia a six. Because of all the different jihadist groups, Iraq is the most dangerous place in the world. I dealt with 45 incidents in the first two months.

What was your riskiest operation?
In Iraq, when I had to make several approaches to some rockets that were on a stuck-fast timer in the desert overlooking our headquarters. Had the timer reasserted itself, I would have been instantly vaporised by the back-blast. It was also 50ºC and I started going into serious heat exhaustion. I was vomiting and getting almighty cramps. As I finished the task, I collapsed.

Couldn’t a robot do it instead?
The robot can do a lot, but it will never have the same dexterity as a human being. I went to some rockets on very steep terrain and it was impossible to get a robot up there. And you have to go in and check, look for secondary devices and gather all the forensics.

Has there been a bomb you just couldn’t fathom?
I don’t mean to sound arrogant, but no. We have to sit 200 exams in 14 months. It’s very technical and clinical.

What protective kit do you wear?
In Iraq, it was so hot, it wasn’t worth wearing the bomb suit. It will protect you when you leave the Incident Control Point, when you’re at risk from secondary devices or sniper fire, but, if you’re leant over a bomb, the blast over-pressure would almost certainly kill you anyway.

Just how scared do you get?
The adrenalin is coursing through your veins and you can feel your heart drumming but, usually, you don’t feel terror.

What’s the most common device?
They fall into three categories: a timed device, like the IRA used in Brighton; a victim-operated device, like the car bomb in Basra; and a command device, which could be a wire or radio-controlled by phone. Nearly 70% of bombs are radio-controlled.

Do all bomb-makers have a signature?
Yeah. It might be the way they wire the device or assemble the components, or it might be the evidence they leave behind. In Basra, the Sunnis always chose the same four wires out of eight in the circuit. When I ended up interviewing the Sunni bomber, he drew me a diagram, so I knew he was my man.

How did it feel facing your nemesis?
I felt an immense hatred towards him for the indiscriminate murders he’d committed, but on the flip side, there was a sort of empathy going on. He wouldn’t talk to anyone else so I appealed to his geeky side. I told him how impressive the devices were, which he loved. He wanted to kill British soldiers, but he also treated it as if he was an artist.

Could you have sorted the bomb on the bus in Speed?
Yes. I can’t give away procedures, but the switch itself was the speedometer, so you could have done something with that to trick the bomb.

Do liquid bombs exist – like in Die Hard With A Vengeance?
Very much so. Lots of people think the airline plots last year are a conspiracy theory but, once the case goes to court, people will realise that the possibility of carnage was phenomenal.

Do bombs ever have countdown clocks, like they do in films?
It’s unusual. In Iraq, they used mechanical timers from washing machines. What was really annoying was that, once they’d set it, they’d take the dial off so you’d never know how long you’d got left.

Do you long for the good old days of IRA coded warnings?
They didn’t do it because they wanted to be sporting but because it was better for their political objectives. But for us it was a fringe benefit, yes. There were agreed codewords, otherwise you’d get the mad, the bad and the sad phoning up.

What’s the most advanced device you’ve come across?
The devices in Iraq at the moment. They use a remote-controlled command signal, then they use an infra-red beam as the firing switch, then they fire a projectile from the side of the road. If you have to bypass all those firing mechanisms, you’ve obviously got a greater chance of dying.

What’s the worst damage you’ve seen done by a bomb?
It was a suicide bombing in Baghdad when I was driving along an infamous road called Route Irish. We hit some traffic and, as it slowed, a car pulled out. The next thing, there was an almighty explosion as it ploughed into the checkpoint ahead. It was carnage, with mangled wreckage of cars, bits of tissue and body blown against walls.

So did you quit bomb disposal while you were still ahead?
Definitely. There’s a huge degree of skill but also an element of luck – and you have to be lucky every time. Two of my team had their legs blown off by a suicide car bomb after I got back. And I’m deaf in my left ear from the effect of lots of blasts. I left the Army in March and now work as a counter-terrorism consultant.

Do you crap yourself now when a car backfires in the street?
I get a bit of a heart flutter, yeah. Or if I’m sitting quietly and my daughter shouts “Boo!”.