Safety precautions and procedures for the construction and descent of machine-bored shafts for piling and other purposes|Foundations, Restraint systems (protective), Safety harnesses, Trenches, Hoists, Hazards, Access, Rescue, Toxic materials, Lifting equipment, Underground, Rescue equipment, Barriers, Earthworks, Hoisting cages, Occupational safety, Air compressors, Pile foundations, Safety engineering, Communication equipment, Construction operations, Accident prevention, Emergency measures, Dangerous materials, Lighting systems, Passenger hoists, Training, Breathing apparatus, Safety measures, Construction workers, Industrial accidents, Personnel, Guard rails, Working conditions (physical), Site investigations, Construction equipment, Piling