Page 62 - OHS, July/August 2020

CONSTRUCTION SAFETY
Trench Safety Difference-Makers: The Perspective of a First Responder
In any trench situation, you need a Trench Competent Person and to notify nearby local fire/rescue teams.
BY TIM ROBSON
Iwill never forget the anguish in that grandmoth- er’s voice as she pleaded with us to save her six- teen-year-old grandson who was trapped under nine yards of soil that had collapsed from an un-
protected trench wall. Unfortunately, my rescue crew was unable to save him. It was not the first time that I had to tell someone that I was sorry for their loss.
Trenches are Inherently Susceptible
to Collapse
This unfortunate incident was totally avoidable. If the contractor had adhered to the well-documented guidelines and a few very easy-to-follow laws, that young man would not have lost his life that day. The laws exist because trenches are inherently susceptible to collapse, and an unprotected, open trench is a haz-
ard, no matter how stable it looks. I have responded to numerous excavation/trench emergencies and to this day, it still amazes me that so many employers willingly decide to allow unprotected trenches to be entered even though there are state and federal laws that require them to be rendered safe before anyone sets foot in one.
Two Difference Makers
There are two things that I see as difference-makers, when I look back at the numerous trench emergencies I have responded to over the years. First, it is abso- lutely essential to have a Trench Competent Person’s involvement from the planning stages onwards. The Competent Person needs to be involved in the soil evaluation, the selection of appropriate protective systems, as well as the daily pre-entry inspections of the trench. This Competent Person has to have docu- mented, trench-specific training and knowledge. And this person must have the authority to stop work when unmitigated hazards exist. In 86 percent of trench cave-in fatalities, there was no Competent Per- son present, so that is a good indicator of how much a Trench Competent Person can be a difference-maker in trench safety.
Second, it’s always a good idea to give advance notice to the local fire/rescue team of the scheduled trench work. Find out where the nearest station is and pay them a visit. They will appreciate the heads- up, and knowing about your project will help them prepare mentally for the possibility of a rescue. They may have knowledge of the jobsite or know of re- sources that will be helpful to you. It’s important not to let this notification lull you into a false sense of security (more on this topic later). Prevention is the best approach.
The Physics and Forces of a Trench Collapse
There is a common misconception that the majority of trench collapse victims succumb to suffocation and airway obstruction injuries. However, traumat- ic injuries and crush syndrome are a leading cause of death due to the large impact forces generated by a vertical trench wall collapse. Even people who have spent years working in trenches often do not realize how great these forces are until it is too late. A combination of Type B and Type C soils weighs
56 Occupational Health & Safety | JULY/AUGUST 2020
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