Gravity. Never, Never, Not Working

There is a silly commercial featuring football players advertising the effectiveness of a dandruff shampoo. The message is how the shampoo is “never not working”.

Gravity is a force that exist anywhere you go on the planet. It is always working; it never takes a break. This means that when we excavate, gravitational forces are always at work acting on the soil, and the result will be a cave-in. There is a 100% chance the soil will eventually cave in. But we cannot predict when that will happen.

The problem is that some people, even in this enlightened safety age, still try to excavate and begin work without concern for that devastating cave-in. For them it’s a roll of the dice. Will today be the day when the inevitable happens?

In the Federal Register there is a reference to soil stability that communicates the problem so well:

“Soil is a difficult material to work with because there is no control over its structural quality. In addition, its properties vary from place to place, and they change with the passage of time due to environmental exposure. There is an infinite number of combinations of conditions and factors that can affect soil stability.”

Another way to say this is:

“Soil is unpredictable except for the predictable cave in”.

Another risk that is taken involves how much will cave in. This is evident when we see inadequate sloping or benching systems. A protective system that is not adequate, can have devastating results just as having no protective system. Unfortunately, history is replete with accounts of cave in fatalities where it just wasn’t sloped enough or the benching was done improperly.

I asked a class one day “What kind of protective systems do you use?”

A hand went up in the back of the room: “We slope everything.”

“How much do you slope?” I inquired further.

The reply was an honest “It depends on how much room we got”.

But it is not funny when an improperly sloped wall collapses and claims a life. It was certainly tragic when the plumber’s improperly benched trench collapsed, breaking his collar bone and puncturing a lung. He was dead before they could free him from the pile of caved-in soil.

If someone truly understands soils, soil mechanics, and what an adequate protective system looks like, and still maintains a “it doesn’t matter what you do, as long as you do something” attitude, they are ignoring reality and are being foolish.

When we excavate, gravitational forces are always at work. It doesn’t take a break just because we don’t want it to be there. The presence of gravity means it will pull down every vertical wall of soil that is not adequately supported or protected, because gravitational forces are stronger than the strength of the soil. Without an adequate protective system, anyone exposed to these dangerous walls of soil are at risk of experiencing serious injury or even death.

Excavation safety competent person training covers the important subjects of soils and protective systems. There are basic ways to make an excavation safe for employees to enter and complete their work without being exposed to a life-threatening cave in. In those challenging situations where an off the shelf system will not work, we strongly suggest enlisting the assistance of a trench shoring specialist who can provide valuable guidance so the job can be completed safely and efficiently.

Never underestimate the destructive force of a cave-in. Do what it takes to make sure an adequate protective system is in place. It isn’t worth the risk because gravity is never not working. Never, never, not working.

For more information on trench safety topics please go to www.trenchandexcavationsafety.com