This one task receives enough citations to be one of the top ten every year among construction related citations. Any time we have employees in the trench, safeguards must be used to insure that injuries do not occur. This is in the OSHA General Clause even though the standard requires protection to start at 4 feet. These standards are to protect you from the hazard of cave-ins and are to be adhered to for your safety. We don’t want anyone to be buried alive due to a cave in!
Some of the provisions are as follows: ·
1.) General requirements
Surface encumbrances that could create a hazard shall be removed or supported’ (anything in the way).
Underground utilities shall be marked as to their estimated location prior to opening an excavation You Must Call the Sunshine State One Call of Florida 48 Hours Before You Dig: 1-800-432-4770. MUST RECALL EVERY 18 DAYS. .
Vehicular traffic exposure of employees to public traffic shall be provided with and required to wear a warning vest.
No employee shall be permitted underneath loads handled by lifting or digging equipment.
A stairway, ladder or ramp shall be located in excavations that are 4 feet or more in depth with no more than 25 feet of lateral travel for employees.
Where a hazardous atmosphere exists or could reasonably exist, it must be tested before employees enter and confined space procedures must be followed.
Employees must not work in excavations that have accumulated water unless adequate precautions have been taken to protect employees against the hazard.
The spoil pile (removed soil) and equipment must be at least 2 feet from the edge of the excavation.
Anytime employees or equipment are permitted to cross over the excavation, walkways or bridges must have guard rails. All wells, pits, shafts, etc. must be barricaded or covered when work is not being performed.
2.) Soil Classification
You must determine the class type of soil you are trenching· in. There are many different ways to test the soil to determine Type A, Type B, or Type C. Type A is the most solid such as solid rock and Type C is loose sand. Most of Florida has Type C soil and this classification should be used to determine how to protect our employees from cave-ins. We should slope our trench walls at a 34 degree angle which is 1 1/2 feet horizontally on each side for every 1 foot in depth.
EXAMPLE: A trench which is 5 feet in depth and 2 feet wide at the bottom shall have each side from the bottom edge with a slope of 1 1/2 feet per foot of depth and an angle of 7 1/2 feet from bottom to top on each side.
To comply with the O.S.H.A. standard, the top of the trench would be 7 1/2 feet for one side, 7 1/2 feet for the other side and 2 feet for the width of the trench at the bottom. 7 1/2 ‘ + 7 1/2 ‘ + 2 = 17 feet across at the top.
This applies to any trade who digs trenches which employees enter to perform work.
From this example you can see why this type of activity is almost .always one of the top ten citations every year.
Be safe, be careful and keep a sharp eye out for cave-ins. We don’t want anyone to get hurt.