Basic Awareness on Excavation Safety

Introduction Openings on any surface are either made for any below-ground Construction /Maintenance activity or have developed due to the erosion of subsoil and the consequent collapsing of the paving above. Working inside these excavations / openings is potentially hazardous and accidents associated this activity are preventable with proper planning and safe execution.

Accidents associated with excavations happen generally due to:
The injuries sustained due to collapse of excavations are usually crushing injuries caused by the sheer
weight of the collapsing material. A Cubic Meter of earth weighs over 1.5 Ton.
 Shoring was not installed where required.
 Shoring failed because it was not frequently inspected or maintained.
 Workers moved beyond the shoring protection.
 Ignorance of underground utilities
 Vehicle / traffic movement very near to the excavation.
 Workers re-entered excavations without inspecting the walls or shoring after rain fall.
 Debris, construction materials and equipment were stored too close to the edge of the excavation.
 Failure to erect barriers around an open excavation.
 Excavation without a banks-man / signal man.
 Working near the HT lines with heavy equipment’s.
 Improper access/egress, damaged or missing ladders or no ramp.
 Workers attempting to jump over excavations.
 Throwing materials down to those working within an excavation – Always use a bucket and rope to lower the tools down.
 Trenches more than 1.2 meter deep are treated as ‘Confined Spaces’, requiring an appropriate ‘permit
to work’. The trenches should have adequate and safe means of exit (such as ladders, steps or ramps)
at no more than 8 meter of lateral travel.
 Use cable / pipe detector and trial pit while doing excavation.
 Manual excavation, if underground services.
 Workers must wear suitable garments marked with high-visibility material.
 Do not permit workers to go underneath the loads of lifting or digging equipment.
 Workers must be protected with individual lifelines and harnesses in bell-bottom excavations.
 Workers must not work in excavations in which there is accumulated water. The water should either be pumped out or adequate safety precautions should be taken.
 Stability of soil shall be checked before start the job.
 The sides of all excavations more than 4 feet deep must be sloped / battered and shored.
 If the soil is loose, shoring may be required for depths less than 4 feet also.
 The shoring should extend to the bottom of the trench and about 12 inches above the top edge.
 Excavations in clay also need as much protection as excavations in loose earth.
 Store excavation debris, equipment and other materials at least 3 feet away from the edge of the
excavation.
 Warning signs, warning tapes shall be provided around excavation. Deep excavation should have hard barricade.
 A competent person must make daily inspections of excavations, adjacent areas and the health and
condition of the shoring material, especially after every rainfall.
 Walkways or bridges are needed for crossing over all excavations. Walkways or bridges over
excavations greater than 4 feet deep require standard guardrails.
 Back fill excavations upon completion. Progress from the bottom of the trench when removing support- system members. Remove the support systems as you backfill the trench.