The hazard
Cranes lift and swing heavy loads near workers and power lines, often on ground that can shift. When something goes wrong, it happens fast. The operator is not the only one at risk: riggers, signal persons, laborers and anyone walking by can be struck, crushed or caught under a load.
The action
The fall zone is wherever a load could fall if something fails, not just the spot below it. In construction, while a suspended load is not being moved, only workers hooking, unhooking or guiding it, making its first connection, or working a concrete hopper or bucket may be in the fall zone. When a load is being landed, only the workers needed to receive it may be there (29 CFR 1926.1425(d)). Everyone else walks around, never under. (29 CFR 1926.1425(b))
ASK THE CREW
Who is our signal person, and what does the emergency stop signal look like?
From the talk: Crane safety. Read it in full, free, with the questions and the sign-in sheet.