TRENCHING IN CONSTRUCTION: HOW TO BE SAFE EVEN WITH ATYPICAL SURFACES

Apr 25

Trenching and excavating – these top the list as the most hazardous operations in our industry. They cannot be avoided, however, as they play a significant role in civil engineering. Being careless or making mistakes could lead to fatalities among your work crew. So, what can you do to keep your job site and workers in the safest possible conditions? In this blog, we’ll not only share with you OSHA’s recommendations, but we will also share an innovative option to keep you trenching safely every time!

Protective Systems

As defined by OSHA, a trench is a narrow underground excavation that is deeper than it is wide and is not wider than fifteen feet. Working in trenches is extremely dangerous as they can result in cave-ins, falls, falling loads, hazardous atmospheres, or accidents that involve mobile equipment. When a trench is five feet deep or greater, OSHA requires that a protective system be used unless the excavation is done entirely in stable rock. Here are the different options for protective systems:

· Sloping: cutting back a trench wall at an angle inclined away from the excavation

· Shoring: installing aluminum hydraulic or other types of supports to prevent soil movement and cave-ins

· Shielding: the use of trench boxes or other types of supports to prevent soil cave-ins

OSHA requires a protective system to be designed by a registered professional engineer (or be based on tabulated data approved by a registered professional engineer) for trenches that are twenty feet deep or greater. In each of those protective system methods, a laborer is in the trench guiding the excavator operator, which puts that person at risk for any of the dangerous situations that we mentioned. That conventional method is the most common practice. However, due to technological advances, companies like ECI Technologies can create 3D utility networks that enable the excavator operator to dig without needing someone in the hole to guide him/her. Not only is this a safer practice, since the less time you have a worker in a trench, the better, but it is also a significant time-saver in your operation.

Safety First

Aside from never entering an unprotected trench, another critical component in OSHA’s trenching and excavating standards is their requirement for a ‘competent person’ to be on-site and conduct daily inspections. According to OSHA, a competent person can identify existing and predictable hazardous, unsanitary or dangerous conditions and is authorized to take immediate corrective measures to eliminate or control the conditions. OSHA also mandates that ladders/steps/ramps or other safe means be located within 25 feet of all workers to enable safe access and egress to all excavations. Over time there have been improvements made in worker safety as well as productivity. Advancements in manufactured systems using tabulated data and site-specific engineered solutions have improved working conditions, but there is always risk in trenching. Contractors must choose the most effective protective system solution for each of their job sites because a one size fits all does not work when it comes to excavating safety.

In Our Experience

Nearly every 3D model that our virtual construction engineers create for our clients includes trenching. Our team’s knowledge base on this subject runs deep. Several of our virtual construction engineers have many years of hands-on experience, having been designated the competent person for their crews when they worked in the field. One of our engineers shared that he most often utilized trench boxes because any trench dug in anything other than Class A material needs support. To keep his crew as safe as possible, he would mainly use shielding. If you’re interested in learning more about utilizing 3D utility networks for your excavating projects, give us a call!

To access OSHA’s standards for trenching and excavating, visit https://www.osha.gov/Publications/trench_excavation_fs.html