How deep can a trench go?

Trenches five feet deep or greater require a protective system unless the excavation is made entirely in stable rock. If the trench is fewer than five feet deep, a competent person may determine a protective system is not required.

Trenches 20 feet (6.1 meters) deep or greater require that the protective system be designed by a registered professional engineer or be based on tabulated data prepared and/or approved by a registered professional engineer in accordance with 1926.652(b) and (c).

The maximum distance between the bottom of the trench box and the bottom of the trench should be no more than 2 feet. A contractor can excavate up to 2 feet under a trench box as long as there's no indication that the soil is collapsing behind the shield or below it and the shield is rated for the full depth.

Atmospheric testing is required before workers enter an excavation greater than 4 feet (1.22 meters) in depth where an oxygen deficiency or a hazardous atmosphere is present or could reasonably be expected, such as in excavations in landfill areas or excavations in areas where hazardous substances are stored nearby.

Trench safety measures

Trenches five feet deep or greater require a protective system unless the excavation is made entirely in stable rock. If the trench is fewer than five feet deep, a competent person may determine a protective system is not required.

Pro Tip: A trencher should be able to dig 100 feet in 12 hours, depending on the type of trench and the terrain.

For excavations greater than 20 ft depth, the slope or bench shall be designed by a registered professional engineer. Sloping means a method of protecting employees from cave-ins by excavating to form sides of an excavation that are inclined away from the excavation so as to prevent cave-ins.

For all trenches deeper than 5 feet deep or for any trench that shows signs of cave-in, OSHA requires sloping, benching, shoring, or shielding to protect workers from cave-ins.

The standard depth for water lines in the U.S. is around 36 inches, but this can vary from location to location. In Colorado and most other places, plumbing regulations are generally based on the International Plumbing Code (IPC) and the International Residential Code (IRC).

In the UK, there is no specified depth that an excavation must be supported*. Current health and safety regulations do not stipulate a depth as it can lead to site teams not paying enough attention to the risks related to a specific excavation, such as: Substrate soil type. Weather conditions.

Sloping, benching, or other approved cave-in protection systems must be utilized in excavations 5 feet or greater in depth. For excavations greater than 20 ft depth, the slope or bench shall be designed by a registered professional engineer.

Trench boxes can be stacked on top of each other as trenches get deeper. Workers can't be in the box when it is being installed, removed or moved vertically. A ladder must be installed within 25 lateral feet of all workers and extend at least 3 feet above the top of the trench.

What you need to do. The law says you must prevent danger to workers in or near excavations. To maintain the required precautions, a competent person must inspect excavation supports or battering at the start of the working shift and at other specified times. No work should take place until the excavation is safe.

Shoring systems give wall support to prevent a trench collapse. Use hydraulic jacks, metal pressure plates, timber piling, or other recognized methods to protect large areas so crews can work inside or beside an excavation without danger of collapse.

Confined spaces include any space that has an open top enclosure of more than four feet in depth which restricts the natural movement of air and enclosures with extremely limited openings for entry or exit.

If you think that you will only need a small trench for a simple project, you may only want to use a shovel. A trench digging shovel can only dig a narrow, flat-bottomed trench, and this will require a good amount of hard labor to complete. If you need a bigger or deeper trench, you will likely need heavy equipment.

Trench Safety: Slope It. Shore It. Shield It.

The image of a soldier in a muddy trench is what many people visualise when they think of the First World War. However, most soldiers would only spend an average of four days at a time in a front line trench. Their daily routine when in the front line varied according to where they were.

Heavy equipment tools like trenchers are ideal for larger trenches or rocky terrain, but shovels and other hand tools can better suit smaller trenches. Trenches can vary in size based on the job and require different tools.

Yes, a trencher will work in wet ground, but be sure you operate with precaution.

OSHA requires employers to provide ladders, steps, ramps, or other safe means of egress for workers working in trench excavations 4 feet (1.22 meters) or deeper. The means of egress must be located so as not to require workers to travel more than 25 feet (7.62 meters) laterally within the trench.

The “6-foot” rule is a general rule of thumb in the construction industry. Basically, it requires that fall protection be provided when work occurs at heights of six feet or greater above a lower level.

OSHA requires that protective systems be in place for all trenches five feet and deeper. Thirty-seven percent of all accidents occur in trenches which are less than five feet deep, so even a shallow trench can be hazardous. However, most fatalities happen in trenches that are five to fourteen feet deep.

There are protective systems that can be utilized to prevent cave-ins. For example, it is possible to slope, shore, and/or shield a trench. Sloping involves cutting a trench wall at an angle away from the trench. Shoring involves placing wooden or metal supports against the trench wall to prevent cave-ins.

Specialized shoring systems, bracing, and/or underpinning may be required to ensure the stability of these structures and to protect workers. Loose Soil or Rock — Spoil piles (and equipment) must be set back at least 2 feet from the edge of a trench or excavation.