Hazard identification, risk assessment and control in crane operations
Identify, assess, control, review
Use a systematic process: identify hazards (from the task, the plant, the environment and people), assess risk by considering likelihood and consequence, apply controls in hierarchy order - eliminate, substitute, engineer, administratively control, then PPE last - and review controls as conditions change. For derrick cranes the dominant hazards are suspended load, structural collapse, rope failure, contact with powerlines, crush zones, wind, ground failure, and falls during erection or dismantling.
Common traps
Questions often present a control that is really PPE or signage and ask you to rank it - it must sit below engineering controls. Another trap is treating a risk assessment as a one-off document: it must be reviewed at each new site, after any modification, and after an incident. Also watch for "the dogger will watch out" - relying on a person to be the only control is a weak administrative control.
Specific derrick hazards
Derrick cranes rely on guys and anchorages rather than a tower or chassis, so anchorage failure, guy slack and mast foot instability are critical. Load swing, drift on the load line, and the geometry of the boom and mast mean the load radius changes with every luff - radius control is a live hazard, not a fixed one.
Worked example
A derrick is to lift near an overhead line. Eliminate by relocating the lift; if not possible, isolate or de-energise the line; then use goalposts or barriers to maintain exclusion; then a spotter; then signage. The spotter alone is not an acceptable single control.
Dynamic assessment
Reassess when wind rises, ground softens, or a new person joins the crew.