6-28 Rescue from a collapsed trench
Fire departments may be called upon to assist with incidents where one or more persons are trapped in a collapsed trench or excavation.
An “excavation” is the hole that is left in the ground as a result of removing material. A “trench” is an excavation where the excavation depth exceeds the excavation width.
Trench rescue requires highly specialized training, equipment and procedures in order for the rescue to be completed safely.
Actions for employers
- provide training to firefighters who may respond to trench rescue situations
- ensure that appropriate personnel, tools, equipment and personal protective equipment are in place to safely perform this work
Trench rescue training and response
Employers should consider including the following content in trench rescue training:
- recognizing the need for a trench or excavation rescue
- identifying the resources necessary to conduct safe and effective trench and excavation emergency operations
- initiating site control and scene management (incident command system)
- recognizing general hazards associated with trench and excavation emergency incidents and the procedures necessary to mitigate these hazards within the general rescue area
- recognizing typical trench and excavation collapse patterns, the reasons trenches and excavations collapse, and the potential for secondary collapse
- recognizing the unique hazards associated with the weight of soil, soil conditions, stability and its associated entrapping characteristics
- initiating a rapid, non-entry extrication of non-injured or minimally injured victim(s)
Firefighters who have not been trained to safely do so should never enter a collapsed trench.
Fire departments that do not provide trench rescue services should have plans in place with other agencies or departments to provide these services in the event that they encounter a collapsed trench where rescue is required.
Applicable regulations and acts
- Occupational Health and Safety Act
- clause 25(2)(a) for providing information and instruction to a worker
- clause 25(2)(d) for making workers aware of hazards
- clause 25(2)(h) for taking every precaution reasonable in the circumstances to protect workers
For a reference guide on responding to incidents involving excavations, read the Excavation safety handbook for emergency responders, developed by the Greater Toronto Sewer & Watermain Contractors Association.