COMMUTERS who have travelled along this country’s major thoroughfares may not realise that they have a Bury manufacturer to thank, in part, for their safe passage.

Ductwork specialist Senior Hargreaves is the national leader for parts used in tunnel ventilation systems.

The Lord Street firm has already provided the huge Saccardo nozzles — which help to transport smoke — for tunnels used in the M25 and the Channel Tunnel Rail Link.

Now Senior Hargreaves is celebrating a third big contract, this time for a tunnel on the Bell Common stretch of the M25, London’s busy orbital motorway.

The contract, which was initiated by the Highways Agency, is with a company called Costain.

Costain is responsible for replacing and upgrading power, lighting, emergency communication, traffic signalling and signage on the M25, in addition to the ventilation upgrade.

With 120,000 vehicles per day passing through the tunnels, delays due to lane closure for unscheduled maintenance are unacceptable, so the pressure is on Senior Hargreaves.

The first use of the firm’s nozzle in the UK was in the Thames tunnels of High Speed One — originally known as the Channel Tunnel Rail Link.

In 2007, the firm fitted a Saccardo system in the Holmesdale tunnels on the M25, which was identical to the system to be fitted in the Bell Common stretch.

The Saccardo systems are used for emergency smoke control as well as general ventilation.

In an emergency, such as a fire in the tunnel, drivers ahead of the incident can drive out of danger. But traffic backed up behind the incident will be protected by the injection of high air volumes to drive smoke away from them to allow for their safe evacuation.

The nozzles will replace obsolete jet fans within the 470 metre long tunnels. The entire Bell Common contract is scheduled for completion by spring next year.