A new OSHA video voiced by U.S. Secretary of Labor Alexander Acosta sends a clear message – OSHA takes trench safety seriously, and you should too. In the short video, Acosta quickly covers five different trench safety practices. Take a moment and see if you can think of five safe trench practices before watching the video.
How many of the safe trench practices listed in the video did you name? While workers need to know more than just these five practices to stay safe when working in and around trenches and excavations, the ones listed in the video are a good start. Let’s take a look at them in a little more detail.
- Ensure there’s a safe way to enter and exit the trench
Conditions in a trench can change very quickly. If you want proof, just look at the videos in our article, “Watch How Quick a Trench Can Collapse.” That’s why workers need the ability to get in and out of a trench on very short notice. In excavations four feet deep or greater, employers must provide ladders, steps, ramps or other means so workers don’t have to travel more than 25 ft. laterally to exit the trench.
All trenches must have cave-in protection
Whether it’s sloping, shoring or shielding, all trenches that are at least five feet deep must be protected. Even a small cave-in produces thousands of pounds of force that can quickly crush, suffocate or trap a worker.
“Stopping trench collapses is critically important because workers rarely survive them,” says LIUNA General President Terry O’Sullivan. “That’s why we have to continue putting such an emphasis on always protecting workers through the use of sloping, shoring or shielding. Those methods work, and they save lives.”
Although it’s still uncommon, some courts have found employers who repeatedly ignore trench protection requirements guilty of manslaughter or negligent homicide when workers are killed in cave-ins. Contractors should never allow workers into an unprotected trench for any amount of time. It only takes seconds for a trench to collapse and take the life of a worker.
- Keep materials away from the edge of the trench
Building materials and equipment should be kept at least two feet from the edge of a trench. This reduces the downward pressure exerted on the walls of the trench, lowering the risk for a cave-in. This practice also reduces the risk that workers handling those materials will fall into the trench or that materials will fall into the trench and strike workers below.
- Look for standing water and other atmospheric hazards
Water should not be allowed to accumulate in or “boil up” from below a trench. Water adds a significant amount of weight to soil, greatly increasing the chances of a cave-in. If water has accumulated from below, either from heavy rains or from another source, it should be removed and a competent person should inspect the trench before work continues.
Atmospheric hazards in trenches can include oxygen deficiency and toxic gases. Employers must test all trenches beforeworkers enter if there’s a reasonable chance of atmospheric hazards. When those hazards are detected, workers have to be protected by engineering controls such as increased ventilation or through the use of respirators.
- Never enter a trench unless it’s been properly inspected
OSHA’s trenching and excavation standard requires a competent person to inspect trenches and the surrounding areas before work begins and throughout the shift as conditions change. A competent person should be able to assess soil stability, different types of soil, the adequacy of trench boxes or support systems and how nearby equipment affects the safety of a trench.
For more information on trenching and excavation, order the Fund’s Safety in the Trenches pocket guide or Excavation and Trench Safety toolbox talk from our online Publications Catalogue. More information and additional resources are also available on OSHA’s Trenching and Excavation page.