07/12/2004

Checklist: Prevent cave-ins and other excavation disasters

Cave-ins, hazardous atmospheres and other risks make excavating and trenching
one of the most dangerous construction activities. An Excavation and Trenching
Pre-Entry Checklist, prepared by the Montana Department of Labor and Industry,
outlines steps that can save workers' lives.

The folowing tips focus on surface encumbrances, underground installations,
access and egress, and traffic safety; but even more dangers may occur like:
hazardous atmospheres, emergency rescue equipment.

Note: Prior to worker entry, a "competent person" -- defined as one who is
capable of identifying existing and predictable hazards in the surroundings, or
working conditions which are unsanitary, hazardous or dangerous to employees,
and who has authorization to take prompt corrective measures to eliminate them
-- must be on-site.

Surface encumbrances


  • Have you checked for structures, machines and equipment, trees or excavated
    spoils located near the excavation which might exert force on the excavation
    walls?
  • Have you checked for any evidence of cracking or subsidence along the
    excavation surface or within the excavation?

Underground installations


  • Are all utilities, such as water, sewer, electrical and telephone, located
    within the excavation properly supported, removed or otherwise protected?

Access and egress


  • Are structural ramps that are used solely by employees for access and
    egress designed by a competent person?
  • Are ramps secured against displacement?
  • Are ramps sound, free from trip hazards and slip-resistant?
  • Are trenches provided with ramps or ladders so that they are within a
    maximum of 25 feet of lateral travel?

Traffic safety


  • Are signs and barricades placed appropriately and in sufficient quantity?
  • Are personnel, where exposed to traffic, wearing appropriate warning vests
    or reflective high-visibility clothing?
  • Are personnel prohibited from working under lifting or digging equipment,
    and required to stand away from vehicles being loaded or unloaded?
  • Where mobile equipment is operated adjacent to an excavation, or approaches
    an excavation, does the operator have a clear view of the edge?
  • Where an operator's view of the edge of an excavation is obstructed, is
    there a warning system, such as hand signals, mechanical signals or stop logs
    in place? (If possible, the grade should be away from the excavation.)

Further Information


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