Struck-By & Caught-Between Hazards

Two of OSHA’s “Focus Four” hazards are being struck by a moving object and being caught in or between objects. Together they kill hundreds of workers every year. Both come down to one idea: know where things can move, and keep your body out of the “line of fire.”

• Construction
• General Industry

What’s the difference?

• Struck-by: an object hits you, and the impact causes the injury. Think of a backing truck, a falling hammer, a nail from a nail gun, or a swinging crane load.
• Caught-in or caught-between: you’re squeezed, crushed, pinched or pulled in. Think of a trench collapse, getting pinned between a skid steer and a wall, or a sleeve caught in a rotating shaft.

The difference matters for investigations, but the prevention is the same: identify the energy (moving vehicles, gravity, rotation, pressure, springs), then keep people out of its path or control it before anyone gets close.

Struck-by hazards and how to control them

Vehicles and mobile equipment

Backing vehicles, haul trucks, loaders, forklifts and highway traffic are some of the deadliest struck-by hazards.

• Wear high-visibility clothing whenever you work near traffic or equipment. See High-Visibility Clothing.
• Make eye contact with the operator, and wait for a signal before you walk into an equipment area. If you can’t see the operator’s eyes or mirror, they can’t see you.
• Stay out of blind spots, especially directly behind and beside equipment. See Backing & Spotters.
• Use a site traffic plan that separates walkways from haul roads, with one-way routes where possible.
• Never ride on equipment unless there’s a seat and seatbelt for you.
• In work zones, set up proper traffic control and stay inside the protected area. See Highway Work Zones.

Falling objects

• Wear your hard hat whenever there’s overhead work. See Hard Hats.
• Tether tools at height and use toeboards, screens or debris nets so material can’t fall. See Tool Tethering.
• Barricade and sign the drop zone below overhead work, and never walk under a suspended load.
• Stack and secure material so it can’t slide or roll off edges and floors.
• Use chutes for debris instead of throwing it down.

Flying objects

• Wear safety glasses, and add a face shield for grinding, chipping and cutting. See Eye & Face Protection.
• Keep guards on grinders and saws, and use wheels rated for the tool’s speed.
• Keep compressed air used for cleaning below 30 psi with chip guarding, and never point it at anyone.
• Use whip checks on air hose connections so a separated hose can’t lash around.
• Treat nail guns and powder-actuated tools like firearms. Know what’s behind the material you’re fastening into.

Swinging and rotating loads

• Barricade the swing radius of cranes and excavators, including the counterweight, so nobody can be struck or pinned.
• Use tag lines to control loads. Never use your hands to steady a load being lifted or lowered.
• Stay out from under the boom and the load at all times.

Rolling and collapsing objects

• Chock pipe, poles and other round material so it can’t roll.
• Brace masonry walls and formwork, and stay out of the limited access zone. See Masonry.
• Set the parking brake, lower attachments and chock wheels before leaving equipment.

Caught-in or between hazards and how to control them

Trench and excavation collapse

A cubic yard of soil can weigh as much as a car. Never enter an excavation 5 feet or deeper unless a protective system such as sloping, shoring or a trench box is in place, and a competent person has inspected it. See Trenching & Excavation Basics.

Between equipment and a fixed object

• Never stand between moving equipment and a wall, column, trailer, or another machine.
• Stay out of the swing radius of excavators and the articulation point of loaders, graders and articulated trucks.
• Never walk between a truck and a loading dock while the truck is moving.

Raised equipment and stored energy

• Never work under a raised dump bed, skid steer arms, blade, bucket or forklift mast unless it is mechanically blocked or cribbed. Hydraulics can fail without warning.
• Release or block stored energy (springs, hydraulics, air, gravity) before maintenance. See Lockout/Tagout.
• Never exit a skid steer with the arms raised.

Rotating parts and machinery

• Keep guards in place on belts, chains, gears, shafts, augers and conveyors.
• Lock out machines before you reach in to clear a jam or clean them.
• Don’t wear loose clothing, gloves near rotating drill bits or lathes, jewelry or long loose hair near rotating parts.
• Know where the emergency stop is before you start work near a machine.

Rollovers

Equipment that rolls over on a slope, at a trench edge or off a ramp can crush the operator. Always wear the seatbelt in equipment with a rollover protective structure (ROPS). If the machine starts to tip, stay in the seat, hold on and lean away from the fall. Don’t jump. See Heavy Equipment Basics.

Pinch points and hand injuries

Pinch points are anywhere two objects come together: doors, hinges, pipe stands, chain hoists, material being lowered onto blocking. Keep your hands out of the gap, use push sticks and tools, and lower loads onto dunnage so you can pull your fingers out.

The line-of-fire check

Before every task, take a few seconds to ask:

• If this moves, falls, swings, rolls or releases, where will it go? Am I in that path?
• Can the operator see me? Have we made eye contact or agreed on signals?
• Is there a way out if something moves unexpectedly?
• Are my hands, feet or body between two things that could close together?
• Is there stored energy (hydraulic, spring, air, gravity) that could release?
• Is the area barricaded, and are the barricades being respected?

Spotters and signals

• Use a trained spotter when backing, when visibility is poor, or near people and structures.
• The operator and spotter must agree on hand signals before work starts. If the operator loses sight of the spotter, the operator stops.
• Spotters stand where they can see the path and the operator can see them, never in the travel path.
• Anyone can give the stop signal.

What OSHA requires

• Vehicles with an obstructed rear view must have a working reverse alarm audible above surrounding noise, or a spotter who signals that it’s safe to back up (29 CFR 1926.601 and 1926.602).
• Crane swing radius areas must be barricaded to prevent workers from being struck or crushed (29 CFR 1926.1424).
• Workers exposed to public vehicular traffic must wear high-visibility vests, and work zones must follow traffic control rules (29 CFR 1926.201 and 1926.651).
• Excavations 5 feet or deeper need protective systems (29 CFR 1926.652).
• Machine guarding is required for points of operation, nip points and rotating parts (29 CFR 1910.212 and 1926.300).
• Protruding reinforcing steel must be guarded to prevent impalement (29 CFR 1926.701).

Last updated: October 1, 2026