Excavation has long been considered an extremely dangerous but necessary part of construction work. Anytime workers are below ground level they are at risk from cave-ins. A trench collapse can easily lead to suffocation and death within minutes, making a trench safety system imperative.
A properly designed trench box system can keep your workers safe and protect your company from the possibility of bankruptcy after expensive lawsuits if a worker is injured. Investing now in trench safety equipment like trench boxes, or shields as they are often called, is investing in the future of your company.
Choosing the Right Trench Box
When considering the right trench box for your particular job site there are many factors that need to be taken into account. You don’t want to put the money into a trench box only to find it doesn’t fit the requirements for the local conditions. Trench shields are built with varying wall thicknesses from three to eight inches thick. The first thing you will need to know to determine what thickness is right for you is what type of soil you are working with. Different soils weigh different amounts and you will need to know how much weight the trench safety system will need to support. The Occupational Health and Safety Administration also has different requirements based on the soil around the trench.
If you are working with a shallow trench and soil with a low unit weight you may find that trench boxes with a three-inch wall thickness are sufficient. Deeper trenches, heavier soils, and soil that has been previously excavated require thicker, stronger trench boxes. Typically wall thicknesses of four to six inches are sufficient for most trenches, however, some trenches may require a box with eight-inch-thick walls depending on the soil.
Stacking Boxes as a Trench Safety System
Very deep trenches may require multiple shields stack on top of each other to allow workers to access the bottom of the trench. Some trench shoring boxes are specifically designed for such work. If your trench is deeper than four feet you will also need to make sure there is a set egress point to allow workers to escape in the event of an emergency. Even if your company keeps some trench shields in the yard, large or deep trenches may require many more boxes to form a complete trench safety system. If this is the case, you may want to look into rental options rather than purchasing and then having to store a large number of trench boxes.
An alternative to trench boxes or shields is hydraulic shoring. Hydraulic shoring is usually much lighter and easier to install than trench boxes. However, if your trench is deeper than twelve feet or particularly wide trench boxes will likely prove to be the best option. Depending on the trench you may be able to combine hydraulic shoring with the trench boxes to allow your workers access to areas of tight fits, such as when working already existing utilities.
Regardless of the particular safety setup, you must always make sure that you are familiar with and up to date on current safety codes. If in doubt speak to a safety officer before renting or purchasing trench boxes to save yourself a great deal of money and many headaches.Google+