The notification of any tunnel or below ground structure project should be the starting point for engagement with the client, principal contractor and responders. There is a statutory requirement for the contractor to provide emergency and rescue capability in tunnels under construction.

The most hazardous phase of the project to be risk-assessed. The outcome of the risk assessment will inform the development of any special procedures, restrictions or limitations to be applied, well before the construction phase commences. The contractor’s risk assessment outcomes and plans must be confirmed in writing.

Refuge chambers should be present in tunnels under construction. A refuge chamber is a place of relative safety in a shaft or tunnel where on-site staff can wait to be rescued or until it is safe for them to exit the tunnel. Refuge chambers should be easily identifiable and readily accessible by anyone at risk.

Special controls and procedures agreed by the contractor must be recorded in the emergency plan and communicated to all partners so they can be implemented quickly and without confusion. Special controls, restrictions or limitations will need to be applied to no through access conditions. These can be created when a tunnel boring machine (TBM) commences boring and the services required to support a fire and rescue service intervention cannot be established for a period of time. In a fire situation, this would mean that the fire and rescue service could only make a limited intervention, as a charged line of delivery hose cannot be dragged for long distances.

A normal control measure applied during these circumstances is for the TBM to be provided with a water mist system to protect walkways, and a rear water curtain to protect the TBM crew, who would remain on-board.

The hand digging of cross passages and the need to enter the cutting head of the TBM both involve working in confined spaces. Such conditions will require the contractor to have special rescue teams available on-scene when work is being carried out, as this responsibility cannot be discharged to the fire and rescue service. Although some fire and rescue service personnel are trained and equipped to work in confined spaces, technical rescue teams are not normally mobilised as part of the fire and rescue service first attendance, resulting in a delay in intervention.

Compressed air working

There is a statutory requirement for fire and rescue services to be notified in advance of compressed air working. At that point, the opportunity should be taken to discuss the limited intervention capability the fire and rescue service can provide.

The task of firefighting or rescuing people employed in compressed air workings is principally the responsibility of the contractor on site. The fire and rescue service might respond to sites where compressed air workings are present and stand by to give advice and provide backup facilities as necessary.

However, subject to any prior arrangement between the contractor and the fire and rescue service, the contractor's responsibilities under the Health and Safety at Work etc. Act should make it unnecessary for personnel to deal with an incident within compressed air workings.

Subject to prior agreement and arrangement, it might be reasonably foreseeable that fire and rescue services could be requested to provide some element of a contractor's emergency arrangements. Breathing apparatus (BA) command and control procedures, appropriate to the risk, should be established along with any minimum provisions for a safe system of work.

Pre-planning and familiarisation

To ensure adequate emergency response, site inspection visits will be essential to familiarise and prepare all responders likely to attend and make an intervention in these environments during construction or when completed.

It may be beneficial to use joint on-site training to gain familiarisation of tunnels under construction.

For further information refer to Tunnels and underground structures supplementary material.