Examples of Hazards from Moving or Falling Objects on Construction Sites

Written by Staff Writer | Edited by Michael Purser

The importance of wearing proper safety gear and staying alert at work can’t be overstated. You must always keep an eye out for falling or flying objects, moving vehicles and uncontrolled materials. Depending on the situation, an unexpected impact can easily cause serious injury or death.

Object impact incidents present major risks at worksites, which is why the Occupational Safety and Health Administration (OSHA) works hard to educate workers and employers about the dangers they present.

Read on to learn more about these hazards, including what they are, the dangers they pose and how you can protect yourself.

OSHA’s Focus Four

Regulators carefully track industry injury statistics and accident reports to better understand the risks workers face on the job. OSHA’s Focus Four represent some of the most common, most dangerous accidents that affect construction workers each year: falls, caught-in or caught-between, struck-by and electrocution.

They are sometimes referred to as the Fatal Four because they cause so many construction fatalities. That’s also why they feature so prominently in general safe workplace training programs like OSHA 10-Hour and OSHA 30-Hour Outreach Training.

What Is an Object Impact Incident?

Struck-by incidents are the result of forcible contact, impact or transfer of kinetic energy between an injured person and an object or piece of equipment.

Most objects on a worksite can become a deadly projectile under the wrong circumstances, so there are many ways that this type of accident can play out. However, OSHA created a general categorization system that makes it easier to discuss these incidents. How many categories of struck-by hazards are there? Four.

You may be injured by a:

1. Flying object
2. Falling object
3. Swinging object
4. Rolling object

There is some overlap between these accidents and caught-in or caught-between injuries. To determine the difference, regulators suggest asking the question: Was it the impact alone that caused the injury?

For example, if an unsecured trailer rolled over someone’s foot and broke their toe, it would be considered a struck-by rolling objects accident. But if the trailer rolled into the person and pinned them between the trailer and a wall, breaking their leg, it would be labeled a caught-between injury.

What Makes These Accidents So Dangerous?

Slapstick routines and kids’ shows often portray these types of incidents as hilariously comedic because, if no one gets hurt, the idea seems funny. The old cartoons with Wile E. Coyote and Roadrunner are a great example. Wile E. Coyote always winds up dropping an anvil on his own head or crushing himself under a boulder.

Unfortunately, the reality is much more deadly. The human body is fragile and easily hurt. Under the right conditions, objects that impact the body, whether flying, falling, swinging or rolling, can cause substantial damage.

Struck-by accidents can be life-altering, life-ending tragedies. OSHA incident reports are full of painful examples:

• Four workers were installing signs on a highway when a pick-up truck changed several lanes and entered the work area. The truck hit one of the workers, knocking him off the road and over a bridge rail. He fell approximately 18ft and died.
• Four workers were struck by an exterior wall while attempting to lift it into place. Three of the workers received bruises and contusions. One of the workers received a fractured leg and was hospitalized.
• Workers were pulling 60-foot sections of pipe out of a hole, using a hoist to stack them on the derrick floor. One of the workers let go of a pipe section before it was secured. As he bent over, the pipe swung around and hit him on the head, killing him.

As demonstrated in the above examples, it only takes a moment of inattention to cause a major injury or fatality.

Common Causes of Struck-By Accidents at Worksites

Every worksite is different, which means the most common causes of struck-by hazards vary from job to job. For instance, if a contract takes place entirely at ground level, the likelihood of being hit by a falling object decreases significantly.

Of the four sub-categories, struck-by rolling objects (vehicles) and falling objects account for the majority of fatalities. Struck-by flying hazards and swinging objects can also be extremely injurious, but they do not cause as many fatalities as the other two types.

Rolling Objects

According to the CDC, vehicles accounted for 47% of construction fatalities in 2019. Powered, non-transport vehicles accounted for 17% of fatalities.

These statistics are probably unsurprising if you have worked around vehicles or heavy equipment before. They represent a lot of mass traveling fast enough to kill someone — even when operated as intended.

Falling Objects

The CDC reported that falling objects accounted for 27% of the fatalities in this category in 2019.

Falling objects can cause:

• Minor injuries like bruises and cuts
• Serious injuries like broken bones
• Severe injuries like paralysis
• And even fatalities

The CDC explains that even light or small objects falling from a sufficient height can still hurt you. The greater the height it drops from, the greater the force it transfers when it lands. It’s all physics.

For example, a tape measure might only weigh a pound, but it could cause serious injury if dropped as few as six feet. A drop of 200 feet or more, on the other hand it could cause severe injury or death.

A two-pound object like a hammer might cause serious injuries if dropped from anywhere from six feet to 20 feet. But at 100 feet or more, the damage is likely extreme.

As weight increases, the height necessary to inflict fatal injuries drops significantly. A five-pound object, such as a brick, might cause serious damage if dropped from a height of just six feet. At 10 feet, the damage could be severe. At 150-200 feet, it could be deadly. And the threat only grows from there.

Protect Yourself and Others from Common Dangers

Hazard identification and hazard mitigation are crucial skills in any construction environment. The Focus Four, including object impacts, pose significant risks that every worker needs to be aware of to prevent workplace injuries. Fortunately, it’s never been easier to get crucial training in those topics.

We are proud to offer the highest-quality workplace safety education courses on the market. Employers and workers across the country rely on us to provide accurate, informative and convenient educational courses. Our course catalogue is extensive, covering more than 150 important subjects across industries.

Our offerings range from comprehensive safety courses like the OSHA-authorized 30-hour Outreach Training to focused certificate courses on topics like fall prevention — including options ranging from a general one-hour primer to New York-specific instruction designed to meet Local Law 196 training requirements.

If you need safety training for construction or general industry, we have a course that’s a perfect match for your situation. And it’s never been easier to get the education you need.

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