Control measure Shoring
Control measure knowledge
Fire and rescue operations occur in many different environments. Some of these will be easily defined as confined spaces, whilst others may not be obvious. Personnel may find themselves having to manage an unstable confined space environment. This may be due to the structure the confined space is in or because of the type of product held in the confined space. Shoring up may be an option that allows an incident to be satisfactorily concluded. However, any shoring operation will need to be carried out by personnel with the full knowledge, training and equipment to carry out the task.
At collapsed structure incidents, it may be necessary to shore elements of the structure to provide sufficient protection from secondary collapse and enable search and rescue operations to proceed at reduced risk. Improvised shoring systems should only be considered if the risk of secondary collapse cannot be avoided or removed.
On-site plant, equipment or materials, propriety trench support equipment or materials suitable for use as trench or pit supports may be available, however, depending on the operational circumstance such equipment may have already failed and therefore a detailed risk assessment should be made prior to consideration of further use.
Depending on the type of environment, many different control measures may be or may become unstable, and actions taken by the emergency services may increase the chances of the ground becoming more unstable or increase the risks involved. There may be pressure to commit personnel before all control measures have been implemented, especially in the case of a live casualty trapped in a trench, for example. Other safe systems of work and procedures may have to be implemented, all of which could slow proceedings down.
Shoring can be described as temporary support to elements of a structure using metal or timber shoring systems and can be provided by urban search and rescue (USAR) teams.
- Temporary stability of structures/debris
- Sufficient protection from secondary collapse to enable search and/or rescue operations to proceed at reduced risk
- Support to vertical, horizontal or sloping surfaces
Shoring used during the construction of underground structures is of extremely high-grade concrete, steel interlocking sheeting or timber to meet the exacting standards set out in the Construction Design and Management (CDM) Regulations and Health and Safety Executive (HSE) guidance. The design and type of shoring will have been decided following engineering calculations that take into account geological conditions, stability of the ground, soil movement predictions and the depth of the excavation or workings. An inspection of the shoring will be conducted daily before work commences. When the factors mentioned above are adhered to, it is extremely unlikely that failure and collapse will occur. Once the shoring is in place, the area within the shored footprint will be excavated by mechanical means to prevent unnecessary hazard exposure to contractor staff.
If a structural failure does occur, resulting in a non-entrapment situation, the duty of care should be handed back to the responsible person on-site because the temporary emergency shoring used by the fire and rescue service to facilitate a rescue would not be suitable to replace the substantive structure.
In a structural failure involving an entrapment, the technical rescue team tactical advisor must consult with the contractor or civil engineer to determine the rescue strategy and the safe system of work that needs to be implemented. It should be noted that the equipment available to fire and rescue service personnel, even when national urban search and rescue (USAR) teams are in attendance, will have limited impact on larger structural failures and therefore co-operation with contractors and other external partners may be required.
- Be aware of national resilience capabilities. This should include an understanding of the arrangements in the National Co-ordination Advisory Framework (NCAF), which should in turn ensure participation in mutual aid and access to resources, such as tactical advisors
- Consider providing local equipment and training to enable improvised shoring at incidents involving collapse or unstable environments
Liaise with the contractor and determine the rescue strategy for a collapse of the structure; this may include arrangements with third-party contractors, for example, providers of cranes
Develop and issue tactical guidance and clearly identify the limitations of technical rescue team resources used to provide temporary emergency shoring
- Assess the structural stability of the working environment before committing crews to a confined space
Liaise with on-site specialist and rescue teams regarding structural stability and shoring capabilities
Consider requesting specialist tactical advice and resources for shoring or access (e.g. USAR, Technical Rescue)