EXCAVATION SAFETY: PROTECTING WORKERS. PROTECTING UTILITIES.
Construction work can be dangerous, and underground construction work can pose even more risk. Cave-ins can be the most dangerous and, statistically, are more likely to occur than other excavation-related accidents that may result in worker fatalities, causing as many as 90 fatalities in the last two years alone.
These jobsite risks and worker tragedies are real but preventable. Prevention starts with the right approach, training and awareness plus the accountability of team members including owners, engineers, supervisors, foremen and competent persons, to help ensure safety on underground projects.
OSHA defines a competent person as “one who is capable of identifying existing and predictable hazards in the surroundings or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has authorization to take prompt corrective measures to eliminate them.” Contractors have a responsibility in choosing the right person based on qualifications and ability to complete their duties, which include: conducting soils analysis, making sure protective systems are used properly and within their design, locating and supporting underground installations, and overseeing water removal operations to name a few.
There is often a misunderstanding that a designated competent person for one activity is automatically the designated competent person for another. A person might know what they need to know about trench safety and shoring, for example, but not necessarily be qualified to inspect scaffolding, conduct a fall hazard analysis or inspect personal fall arrest systems. For that reason, a large jobsite may require more than one competent person experienced and knowledgeable around those specific safety hazards.
To help eliminate cave-ins that have the potential to damage utilities and harm workers in underground construction, pre-planning must be adopted. If contractors are not including safety measures in the project submittal process, they may be increasing their risk of a cavein incident. Utilities, worker safety, and lives and are at stake. We can’t just “run with it.”
When choosing a protective system, OSHA provides five compliant solutions that, when applied properly, help prevent a cave-in risks:
- Slope/Benching
- Hydraulic Shoring
- Timber Shoring
- Manufacturer’s Tabulated Data
- Site-Specific Engineering
Some important factors, like soil type, size and depth of the excavation, adjacent structures, water, and crossing utilities all need to be considered to choose the right solution. Having a game plan helps the competent person ensure worker safety.
CPWR (The Center for Construction Research and Training) recently conducted a Trench Survey (cpwr.com/publications/reports/safety-hazards) to provide greater insight into the rise of trench fatalities. Survey responses between CPWR, United Rentals and Speed Shore Manufacturing revealed a couple of important findings: (1) there is a need for more pre-planning on projects, and (2) trench projects often do not have a competent person on site.
Despite all the advancements in architecture, engineering designs, equipment solutions, and safety, trench fatalities continue to be on the rise. Consulting with experts and engineers for proper training and protective system solutions should be a best practice to mitigate risks to workers and underground installations.
Joe Wise is Regional Customer Training Manager with United Rentals. He can be reached at jwise@ur.com.
