Minimising risk from them is the challenge. Preferably, and in general, some prior thinking gets done. Ways and means are put in place to reduce the consequences arising from problems. Systems. Technologies.

Choice made draw upon research into local precedent and industry experience, and standards, and guidance, as well as new scientific insight to think about possibilities, perhaps probabilities.

Below ground, a similar approach is needed to address safety issues – the systems-thinking and engineering required to address risk from instances of fire, for example. Instances might occur at equipment during the construction phase of a tunnel project or, many years later, in the operational life of such an infrastructure asset in public use – a busy road tunnel, say.

In this issue, we look at number of aspects of tunnel safety systems with regard to fire, such as with ventilation and smoke control, software modelling, sensors for temperature and heat, water-mist fire suppression, and also spalling of concrete. Engineering in the face of uncertainty.

Planning for, and executing, works underground also has uncertainty built in with a fundamental aspect, as every tunneller knows: geology. T&T is pleased to carry the winning paper from the most recent BTS Harding Prize Competition, earlier this year, that looks at how the latest new technological wave – artificial intelligence – was tested on a live TBM project, with good results.

The paper looks at the approach developed to forecast tunnelling progress and the modelling holds out possibilities for application in future to other projects, both before the works (eg tendering) and during (for what is ahead).

Technology takes industry far, but not without the contribution of key people. So, it is with pleasure that in this issue we spotlight the recognition given by the BTS to its James Clark Medal winner – Andy Alder.