Being struck by an object or equipment is the most common cause of crane-related fatalities, accounting for just over half of all fatal crane injuries in the United States. This broad category includes workers hit by the crane’s boom, its load, or other components that swing, fall, or collapse during operation.
How Struck-by Deaths Happen
The “struck by” category covers several distinct scenarios, but two stand out. Data from the Center for Construction Research and Training, covering crane deaths in construction from 1992 to 2006, found that 18% of all crane fatalities involved workers being struck by the crane’s boom or jib, the long arm that extends outward to lift loads. Another 7% involved workers struck by the load itself, whether it slipped from rigging, swung unexpectedly, or fell during placement.
Boom strikes often happen when the crane rotates or lowers and a worker on the ground or on a nearby structure is in the swing path. Load strikes typically involve rigging failures, where a sling breaks or a load shifts mid-lift, or situations where a worker walks beneath a suspended load. In both cases, the forces involved are enormous. Even a relatively small crane load can weigh several tons, and a boom can swing with enough momentum to be fatal on contact.
Crane Tip-overs and Collapses
Crane overturning causes about 11% of fatal crane events. While less common than struck-by incidents, tip-overs tend to be catastrophic, often killing not just the operator but bystanders and other workers in the collapse zone. The most frequent contributing factors, in order, are overloading the crane beyond its rated capacity, losing control of the center of gravity, outrigger failure, high winds, side-pulling loads at an angle, and improper maintenance.
Overloading is by far the biggest driver. Every crane has a load chart that specifies how much weight it can safely lift at a given boom angle and radius. Exceeding those limits, sometimes by as little as 10 to 15 percent, can shift the machine’s center of gravity past its tipping point. Soft or uneven ground compounds the problem. If outriggers sink into soil that hasn’t been properly compacted or assessed, the crane loses the stable base it needs to handle heavy loads.
Electrocution From Power Lines
Contact with overhead power lines is another major killer in crane operations, though the research data doesn’t assign a single clean percentage. What makes electrocution especially dangerous is how quickly it happens. A crane boom or cable only needs to come within a few feet of a high-voltage line for electricity to arc across the gap. The operator, riggers, and anyone touching the crane or its load can be killed instantly.
OSHA dedicates multiple sections of its crane safety standards specifically to power line hazards, requiring operators to maintain safe distances from energized lines and to follow specific procedures when work must happen near them. Despite these rules, power line contacts remain one of the most preventable yet persistent causes of crane deaths, often resulting from inadequate site surveys that fail to identify overhead lines before the crane is set up.
Who Is Most at Risk
The workers killed in crane incidents are not always crane operators. In fact, ground-level workers, riggers, signalpersons, and ironworkers are frequently the victims in struck-by incidents because they work in the crane’s operating radius. Operators face their greatest risk during tip-overs, when the cab rolls or collapses, and during electrocution events, since they’re physically connected to the machine.
Construction accounts for the largest share of crane-related deaths, but cranes are also used extensively in manufacturing, utilities, oil and gas, and maritime industries. The hazards are similar across sectors: heavy loads moving overhead, large machines operating near workers, and the ever-present risk of contact with power lines or structural collapse.
What Prevents These Deaths
Most crane fatalities trace back to a handful of preventable failures. Overloading, poor site assessment, inadequate communication between the operator and ground crew, and failure to identify overhead hazards before starting work are recurring themes in fatal incident investigations.
OSHA’s crane safety standards for construction require operators to be certified and to follow the manufacturer’s load charts at all times. The rules mandate specific procedures for working near power lines, including minimum clearance distances that increase with voltage. Fall protection requirements cover workers on crane structures, and detailed protocols govern how cranes are assembled and disassembled, phases that carry their own serious risks.
On the ground, the most effective protection is maintaining a clear zone beneath and around suspended loads. No worker should stand or walk under a load being lifted, and the crane’s swing radius should be barricaded whenever possible. For tip-over prevention, the critical steps happen before the first lift: assessing ground conditions, properly deploying outriggers on stable surfaces, and verifying that the planned lifts fall within the crane’s rated capacity at the actual working radius.