Trench Rescue Awareness for EMS

“Engine 1, Squad 2, Ladder 5, Medic 631, respond to 14 Paradise Place for a report of a utility worker trapped in a trench with unknown injuries.”

This dispatch is not common for most EMS and fire departments. But when a call like this comes, is your department prepared to respond to a trench-rescue incident, and are your providers trained in what to do? The purpose of this article is to provide some awareness-level information for use when responding to a technical rescue in a trench.

Types of Trenches

While trench rescues may not be common, trenches are. Often at construction sites, trenches are dug for workers to install or repair underground utilities, including water pipes and electrical, cable, Internet, and sewer lines. These types of trenches are often narrow and deep, descending anywhere from 4–15 feet. They can be straight lines, intersect in T, L, or X shapes, or be perpendicular. Different from a trench is an excavation, which is a wide and deep hole often used for repairs to streets, gas lines, or water mains. At times workers operating in excavations will be using a protective “trench box.”

Cave-In or Not?

If an emergency occurs in a trench, is it typically either a cave-in or a non-cave-in. A cave-in is due to either changing weather, soil conditions, machinery, or vibrations that cause the walls to collapse or removed dirt (the spoil pile) to fall back into the trench. A non-cave-in trench emergency can consist of a worker having a medical emergency in the trench, entrapment of a worker under a pipe or machinery, flooding, or equipment failure.

Establishing Command and Requesting Resources

It is crucial that first-arriving units take steps to establish command, contain the incident, and request appropriate resources.

Establish command according to incident command guidelines and set up a command post. If the first-arriving unit is not command staff, transfer command when it arrives. Initial duties should include:

• Notifying dispatch;
• Sizing up the situation and determining if it is a cave-in or non-cave-in. Additional size-up should include:
  • Number and types of victims
  • Nature of the emergency
  • Hazards on scene (utilities, weather, water, hazmat, machinery)
  • The type and approximate depth of the trench
  • Whether it’s a rescue or recovery operation;
• Establishing hot, warm, and cold zones. Personnel not trained in trench rescue should not be in the hot zone, meaning they should not be inside the trench or within a 6–10-foot radius around it;
• Making sure other arriving responders resist the urge to play hero and enter the hot zone. This is a technical rescue, and responders need to be technically trained;
• Making sure all machinery on the site is shut down and nontrapped personnel move away from the hot zone;
• Establishing a staging area for equipment and personnel coming to the scene.

A trench rescue incident requires a technical rescue team. Whether you have personnel and equipment within your department or need to request help from another agency, activate this team. A minimum of 20–30 trench rescue technicians are needed for an operation.

Specialized Equipment

Responders from the trench rescue team will bring in specialized equipment. This includes tools like air bags, struts, shoring, hand tools, buckets for dirt removal, ladders, ground pads or plywood to stabilize the area around the trench, rope and rigging, generators, and lighting. If weather is a factor, heaters might be needed. Additionally, many teams utilize a vacuum truck to help with dirt removal. For extended incidents consider additional resources such as food, hydration, and warming areas for rescuers.

Personal protective equipment should consist of, at a minimum, a helmet with chinstrap, eye and ear protection, steel-toed boots, gloves, and either coveralls or a protective clothing ensemble.

Medical Considerations

Two feet of soil on a victim can be the equivalent of 600–1,000 pounds on their body. Clearly crush-type injuries and airway compromise are strongly possible. Once EMS can access the victim, the following should be treatment priorities (confirm with your local medical director/medical control):

• Airway access and control;
• Oxygenation;
• Maintaining body temperature through warming;
• Intravenous or IO access prior to full patient removal;
• Head, eye, and ear protection for the victim while the rescue is taking place to prevent further injury;
• Pain management;
• Fracture management and immobilization.

Once the victim is removed from the entrapment and trench, there may be a need for gross decontamination prior to transport, especially if hazardous materials or large amounts of dirt/mud are involved. Working with your local hazmat team can assist with this process.

It is highly encouraged that all responders take a trench rescue awareness and/or operations class that meets NFPA standards. While trench rescue calls are rare, they are technical operations requiring a great deal of personnel, resources, and logistics.

Barry A. Bachenheimer, EdD, FF/EMT, is a career educator and university professor, as well as a firefighter and member of the technical-rescue team with the Roseland (N.J.) Fire Department and an EMT with the South Orange (N.J.) Rescue Squad. With an emergency services career of more than 30 years, he frequently serves as an instructor for both departments. He is also co-owner of Jump Bag Training Company, LLC. Reach him at barry@jumpbagtraining.com.