What does getting struck by a pickup traveling 45 mph and being in the path of a trench wall collapse have in common? The outcome is typically not going to be positive…
A six cubic yard section of trench wall that collapses into an 8 foot deep trench has the weight and speed of a full size pickup traveling 45 mph.
These forces are the reason why a proactive and compliant trench safety program is paramount to your safety as a worker or as a rescuer!
Unfortunately, there was another tragic incident last week in Las Vegas, New Mexico, in which two workers were killed following a trench cave-in. Dirt buried 49-year-old Frank Romero and 32-year-old Gene Hern. The men were installing sewer and water lines in the 8 to 10 foot deep trench. City spokesperson Dave Romero says other workers frantically tried to dig the men out but didn’t make it to them in time. Hern and Romero were pronounced dead on the scene by medical officials.
This serves as another reminder of how important it is to be trained in the proper precautions and dangers of trenches and excavations. Once it happens, it’s too late, there’s no time to prepare. As a first responder, be aware when this type work is going on in your district or response area – don’t take chances, know how to protect yourself. And, if you’re involved with the project from the beginning, preplan each job with the utmost precaution.
According to OSHA, excavation and trenching are among the most hazardous construction operations. This type work presents serious hazards to all workers involved. Cave-ins pose the greatest risk and are much more likely than other excavation-related accidents to result in worker fatalities. Other potential hazards include falls, falling loads, hazardous atmospheres, and incidents involving mobile equipment. The regulation that covers requirements for excavation and trenching operations is OSHA 1926.650.
What’s the difference between an excavation and a trench?
OSHA defines an excavation as any man-made cut, cavity, trench, or depression in the earth’s surface formed by earth removal. This can include excavations for anything from cellars to highways. A trench is defined as a narrow underground excavation that is deeper than it is wide, and no wider than 15 feet (4.5 meters).
Why is it important to preplan the excavation work?
No matter how many trenching, shoring, and back-filling jobs you have done in the past, it is important to approach each new job with the utmost care and preparation. Many on-the-job accidents result directly from inadequate initial planning. Waiting until after the work has started to correct mistakes in shoring or sloping slows down the operation, adds to the cost, and increases the possibility of a cave-in or other excavation failure.
A big part of being safe, is being prepared. Knowing as much as possible about the job or work site and the materials or equipment needed is a best practice. Here are a few things OSHA recommends you consider about the site.
2. Proximity and physical conditions of nearby structures
4. Surface and ground water
5. Location of the water table
6. Overhead and underground utilities
7. Weather conditions
OSHA Excavation and Trenching Standard applies to all open excavations made in the earth’s surface, including trenches. Strict compliance with all sections of the standard will greatly reduce the risk of cave-ins as well as other excavation-related accidents. See the resource below to learn more.