Civil engineers do not have a risk free working life. We all know that the accident record in the industry leaves a lot to be desired, with 62 fatalities between April and September last year, compared to only 39 over the same period the year before. But there are clearly some areas of the sector in which the risks are particularly high - such as tunnelling, roped access, diving and emergency work. So do workers involved in such activities experience fear every time they don their protective clothing - or are they too gung ho for that?
Aidan West, managing director of Osiris Marine Services, which specialises in diving and underwater engineering, stresses that fear is part of the territory.
'Divers do get killed - it is as simple as that, ' he says. 'Fear is part of your working day.
'You are not meant to be underwater - you need breathing equipment, it's exhausting and it's cold - I have worked in temperatures 2degreesC-3degreesC below freezing. Seawater does not freeze at that temperature because of the salt content.
West has been close to death himself, and has seen a colleague freeze to death while trapped under the sea. He points out that fear can be useful. Most diving engineering work is done in zero visibility in industrial ports where the sea is dark with silt - so divers develop what he calls 'a 3D mind's eye' - the ability to sense what is going on around them.
But fear can also be disabling.
When West worked on the Medway Tunnel, he came across one young diver who could not cope: 'He was straight out of diving school, did the job for one day and that was enough, ' says West. 'He walked off, leaving his diving equipment behind, and never came back.'
According to Andy Fewtrell, managing director of consultancy Up and Under, which specialises in getting access to areas which are difficult to reach, it is the degree of fear which makes the difference: 'I would not take on anyone who said - I have no fear, ' he says.
'You need experienced, level headed people who know the environment - if you are working 100ft in the air, you do not do anything casually.'
On the other hand, extreme fear has no place in any aspect of construction, Fewtrell asserts.
'Things should never get to that stage, ' he says. 'Experiencing pure fear means you have a sense that the situation is out of control. Anyone in our line of work should have taken steps to stop that from happening.'
Fear is inspired by more than just physical danger. Laura Haig, group safety manager with Mott MacDonald, points out that going abroad to a new post can get pulses racing for engineers who have no problem with heights or confined spaces. 'It's the fear of the unknown, ' she says. 'Selection is very important. Before expecting people to go overseas, we look at personal circumstances, experience, levels of fitness and resourcefulness.'
No matter how alarming employees of Mott MacDonald may find the prospect of a foreign posting, they are unlikely to be put in a situation of extreme danger.
Specialist organisation RedR selects and trains volunteers for disaster relief. It sends engineers all over the world to renew infrastucture in places as volatile as Sierre Leone, Angola and Rwanda. Training manager Tim Hayward says fear can be reduced by taking safety precautions - even in a war zone - and the firm runs courses to alert staff to the ground rules.
'We give engineers advice about the local political situation, and about practical matters like staying in touch and knowing where it is safe to go and where is high risk, ' says Hayward.
'We also have steps laid down for evacuation procedures and for lying low somewhere if violence erupts and you have to wait for the situation to calm down.'
What is the role of fear in this line of work? Again - it has its uses. 'Fear can help you be alert, ' says Hayward. 'If you were not afraid on some level, you would be complacent, not observant or aware. And you have to be aware.'