Operations and Signaling
Domain 4: Operations and Signaling
The exam tests coordinated control: one clear signal source, standard signals, smooth load handling, and knowing when to stop.
Core rules
- Use one designated signalperson. The operator follows that person's signals, but any person may give an emergency stop signal. If a signal is unclear or communication is lost, stop and hold until communication is restored.
- Hand signals follow ASME B30.22/OSHA standard signals: hoist, lower, boom up/down, swing, stop, emergency stop and travel. Radio or voice signals must be tested before the lift and use a dedicated channel with fail-safe language; "stop" means stop.
- Before the lift, confirm load weight, rigging, chart, radius, outrigger set-up, exclusion zone and power-line clearance. Use tag lines to control the load.
- Start and stop smoothly; avoid shock loading, rapid slewing and dragging or side-pulling the load. Travel only in the manufacturer's approved configuration; for most articulating cranes that means boom stowed and outriggers retracted unless the manual permits otherwise.
- Watch the anti-two-block device, boom articulation pinch points and load path. Never move a load over people.
Worked example
An operator is booming down when the load disappears behind a wall and the signalperson's radio goes silent. The correct response is to stop the function and hold the load, then re-establish communication with a qualified signalperson who has a clear view or reliable radio. Continuing on an assumed signal-or following a bystander's wave-violates the one-signalperson rule and is a common exam failure point.
Traps
Following multiple signalers, using a cell phone as the only signal link without a backup plan, moving before the rigger confirms the load is free, ignoring wind or load swing, and traveling with a suspended load without manufacturer approval.