Focus Four Hazards: Struck-By
Falling and flying objects
Struck-by injuries occur when a person is hit by a moving object: falling tools and materials, swinging crane loads, rolling pipe, flying fragments from a saw or nail gun, or a vehicle. Controls are layered. Protect the head with a hard hat, install toe boards and debris netting, use tool lanyards and tethers, secure stacked material, close or cover holes, and barricade ground areas beneath overhead work so that employees are never required to work under a suspended load.
Vehicles and equipment
Backing equipment is a classic struck-by source. Use spotters, back-up alarms, mirrors, internal traffic control plans, designated pedestrian routes, high-visibility apparel, and barricades that separate foot traffic from equipment. Operators and passengers wear seat belts.
Rigging and masonry
Barricade the swing radius around cranes, inspect rigging, use tag lines to control loads, and never ride the load. Masonry walls require a limited access zone during construction.
Traps
The exam tests the boundary between struck-by and caught-in/between. A hammer that falls and hits a worker is struck-by. A worker pulled into a running auger, or crushed between a crane counterweight and a wall, is caught-in/between. Also remember that a hard hat protects against impact but not against a load that exceeds its rating - the real control is barricading and exclusion, not better headgear.
Rule of thumb: ask whether the object traveled to the person (struck-by) or the person was pinched, crushed, or drawn into something (caught-in).