BRITAIN'S FIRST road tunnel design codes are to be published by the Highways Agency this summer - after nine years of preparation.
For nearly a decade, tunnel designers have been using a collection of temporary and outdated standards. The new document, BD78: The Design of Road Tunnels, will provide the first common framework for road tunnel designers and operators.
The code will tackle the key areas of design such as ventilation, parallel service tunnels, monitoring systems and emergency procedures - all highlighted as factors leading to the high death toll in last week's Mont Blanc Tunnel fire.
The long delay in publishing the important safety guidelines has been blamed on Highways Agency reorganisations and the pace of technological advances.
'Part of the problem is that people retire and we have to reorganise every year. Also technology moves on,' explained the Highways Agency's senior tunnelling advisor Robert Ford.
The new code has been prepared with the Transport Research Laboratory and the world road association PIARC. It will set out guidelines and advice for road tunnel designers and operators. But although road tunnel designers have relied on a collection of draft copies of the new code, international standards and their own experience and knowledge, they remain split over the value of the new code.
'Every tunnel is different,' said one leading consultant. 'Even with a code each tunnel still has to be judged on its own merits. It's horses for courses.'
Others claim incidents like the Mont Blanc and Channel Tunnel fires point to the need for generic risk management of issues such as communications, testing of equipment and monitoring.
Tunnel operators in the UK are also divided over the value of the new guidelines.
'I'm not enormously impressed,' said one operator. 'PIARC has done a lot of research into fires and flows, but from one year to the next it has different lines of thought. There could even be an argument to say don't have ventilation. Every tunnel performs differently.'
But general manager of Britain's longest road tunnel, the Birkenhead Tunnel, John Gillard, said: 'Over a long period of time tunnels have been designed with engineering judgement. The harmonisation is good. I didn't expect it to take so long but I welcome it.'
However, in the wake of the Mont Blanc fire, UK tunnel operators insisted that their tunnels were safe, despite being designed before the new guidelines.
General manager for the 1.6km long, single bore, dual-traffic flow Tyne Tunnel, Brian Middleton, said: 'We have developed our own safety plan together with the emergency services. We have colour, closed circuit television with no blind spots and a permanent patrol inside the tunnel. We also carry out full scale emergency drills every year.'