Hazard identification, risk assessment and control measures
Hazard identification for crane work is systematic. Consider the task, the plant, the environment and the people. Task hazards include suspended loads, crush zones, snagging, shock loading and blind lifts. Plant hazards include structural failure, rope failure, brake failure, limit switch failure and instability. Environmental hazards include ground bearing failure, wind, slope, excavations, underground services, overhead lines, heat and poor lighting. People hazards include fatigue, distraction, poor communication, untrained personnel and pedestrians entering the zone.
Risk assessment ranks likelihood and consequence, then selects controls using the hierarchy. A useful discipline is to ask what could go wrong at each stage: rigging, set-up, boom up, slew, hoist, travel and pack-up. Consider both the planned lift and foreseeable deviations.
Traps in questions include naming a hazard when asked for a risk, or naming a control when asked for a hazard. Another trap is ignoring the "what if" scenario: what if the load hangs up, what if the wind gusts, what if the outrigger sinks. Secondary hazards such as the load swinging after a rope breaks are frequently missed.
Rule of thumb: hazard equals source of harm; risk equals the chance and severity of that harm; control equals what you do about it. Worked example: a lift over a live sewer. Hazard is the excavation and collapse; risk is the crane tipping into it; controls are verified ground bearing, mats or spreader beams, outrigger clear of the excavation at a safe distance, a spotter, and a revised lift plan with reduced radius.