Excavation hazards and precautions:- "{ Click for the video(In hindi) }" Most construction work involves some form of excavation of building foundatios, sewers and underground services. Excavation work involves the removal of soil or a mixture of soil and rock. Soil varies in it's nature. It could be fine sand which flows easily, and stiff clay which is more cohesive. Water is nearly always present in the soil, even if only as moisture. Heavy rain is a frequent cause of soil slip. The possibility of flooding presents the additional hazard which should always be considered. Cracks are caused by pressure release as soil is removed, or dried out in hot weather. These things makes excavations or trenching work highly dangerous and even some je the most experienced people get caught by the sudden and unexpected collapse of the unprotected sides of a trench. Buried under a cubic meter of soil, a person is unable to breathe due to pressure on the chest. Apart from ge...