Slips, trips, and falls cause most head injuries at construction sites. But simple preventive measures—including hard hats—can help

Tactical helmets save lives on the battlefield, preventing fatalities from falls, parachute drops, vehicle collisions, and projectiles. But for construction workers—including the hundreds of thousands of former military personnel who join their ranks—head injuries are also a threat.

This article looks at the prevalence, causes, and aftermath of construction site injuries impacting the head and brain. We also explain how safety measures, including fall prevention and rigorous hard hat design, can prevent or mitigate harm on the job.

Many factors contribute to head injuries on construction sites, but falls are the leading culprit

Construction outpaces all other industries in the overall number of fatal and nonfatal traumatic brain injuries (TBIs) suffered.

It's not the riskiest line of work, however: TBIs have happened with greater frequency in some sectors, like mining and agriculture. And thankfully, the rate of TBIs in construction has fallen. In 2016, The Centers for Disease Control and Prevention (CDC) noted that a mix of economic factors and a declining overall rate of workplace fatalities had long been cutting the occurrence of deadly TBIs. While more than 2,200 construction workers died of such causes between 2003 and 2010, fatalities fell by an average of 6.2% each year.

But a 2011 study from the American Journal of Preventive Medicine found that there were 2.7 fatal TBIs per 100,000 workers in construction each year—more than triple the average rate across all industries. Given the large number of people employed, this higher-than-average risk represents a tragic number of deaths, with head injuries accounting for as many as 1 in 4 on-the-job fatalities.

Those head injuries have various causes, including car accidents, assaults, and collisions with objects and equipment. And some construction trades, like structural iron and steel or roofing, have significantly higher injury rates than others.

More than half of construction-related TBIs occurred during falls—often from a ladder, scaffold, or roof. Falls are the primary source of construction site accidents overall as well as those in other industries. Data from the U.S. Bureau of Labor Statistics show that falls, slips, and trips remain the leading cause of injury in American workplaces, with more than 300,000 such incidents recorded between 2018 and 2019.

Safety gear is essential. A sizable number of construction site injuries (and on-the-job TBIs) involve falls. Image source: PEO ACWA

While bone-shattering head injuries are infrequent in construction, incidents leading to brain damage happen more frequently

Much of the available research focuses on fatal head injuries. But construction accidents vary in severity—and even a "mild" incident can have a life-long impact. 

Traumatic brain injuries can be classified according to their impact on the skull: open TBIs involve a break or fracture, while closed TBIs don't. But even closed TBIs can cause serious harm, such as internal bleeding, degenerative brain diseases, and death.  

Another factor, particularly where falls are involved, is the type of impact that caused the injury. Collisions hitting the head straight-on generate linear acceleration (motion in a straight line) and are associated with conditions like skull fractures. Impacts at an angle, like when a person lands on the side of their head, produce rotational acceleration. Research indicates that these forces are the leading culprit in concussions, along with the release of blood between the skull and brain (subdural hematoma) and other serious conditions.

Rotational forces can effectively rattle the brain inside the skull, causing damage that may be harder to detect. Image source: Patrick J. Lynch via Wikipedia (CC BY 2.5)

It's difficult to estimate the exact frequency of different TBIs in the industry. But available research suggests that construction injuries typically take milder forms. For example, a 2021 study of TBIs among German and Swedish construction workers found that:

• Bone fractures (open TBIs) are rare, making up only 3.8% of construction-related head injuries in Sweden and 5% in Germany
• Concussions are more frequent, comprising roughly 15% of Swedish injuries and 27% of German ones
• Superficial injuries not involving a concussion are far and away the largest category, comprising half or more of the total in both nations

These numbers may understate the problem, however. While open TBIs are easy to recognize, closed TBIs sometimes go unreported. Headway, an English charity concerned with brain damage, surveyed English laborers as part of its annual “Hard Hat Awareness Week.” The organization found that more than half of construction site injuries affecting the head weren't disclosed—at least in part because those injured didn't think their condition required attention.

Fall prevention and head protection are essential in minimizing construction site injuries

Falls remain the most significant concern, causing most of the industry's fatal TBIs and 1 in 3 deaths overall. In response, leading safety organizations like the National Institute for Occupational Safety and Health (NIOSH) have spearheaded a range of efforts to make workplaces safer, including the National Campaign to Prevent Falls in Construction. Among other things, they emphasize:

• Educating workers and employers on fall hazards
• Training and education on extension and step-ladder safety
• Proper use of required fall protection equipment, including fall arrest lanyards, lifelines, and anchorage

With the right training and equipment, workers can reduce the likelihood of construction site injuries caused by falls. Image source: Miller and Long Co., Inc./elcosh.org/CWPR

But wearing proper protective gear—like helmets—is also critical. The vast majority of American businesses are subject to rules issued by the Occupational Safety and Health Administration (OSHA). OSHA requires protective helmets for those "working in areas where there is a possible danger of head injury from impact, or from falling or flying objects, or from electrical shock and burns."

Yet some estimates have found that only 16% of those who suffered a head injury were wearing hard hats—even though more than twice that number should have had one. And the industry is littered with tragic examples of workers who failed to wear protective gear properly, making helmets less effective. For example, some individuals don cold-weather gear underneath the helmet. Others wear hard hats backward to maneuver through tight spaces.

These and other simple mistakes may prevent protective helmets from properly absorbing impacts, making construction injuries unnecessarily severe.

Hard hats' design makes collisions less intense, reducing the severity of head-related construction injuries

OSHA rules have made hard hats a staple of construction sites for decades—and those rules, in tandem with other safety provisions, have cut worker deaths by roughly two-thirds since 1970. In fact, some research shows that OSHA-compliant protective helmets can reduce some forms of acceleration by as much as 95%.

Every OSHA-required hard hat must meet standards provided by the American National Standards Institute (ANSI). The American National Standard for Industrial Head Protection (ANSI/ISEA Z89.1) divides protective helmets into two types: those that defend only against blows to the top of the head (Type I) and those that also mitigate impacts from the back, sides, and other angles (Type II). Headgear is further classified according to its ability to withstand electrical shock:

• Class C (Conductive): No electrical protection
• Class G (General): Tested to 2,000 volts
• Class E (Electrical): Tested to 20,000 volts

Each manufacturer must submit samples to laboratories, which use specialized machines to evaluate products' performance against heat, cold, flame, impact, and other risks. In the video below, a technician at Cadex—a company specializing in helmet testing technology—uses an anvil-bearing machine to conduct ANSI Z89.1 tests that measure linear impact attenuation (in essence, shock-absorption):

Through these and other tests, ANSI Z89.1 helps manufacturers and employers establish that their hard hats:

• Resist fire damage. A test flame is applied to, and removed from, the helmet; if fire is visible on the helmet five seconds afterward, the helmet fails.
• Absorb shock. To pass the test, an anvil dropped on the helmet must slow the transmission of force to the "headform" (a specialized dummy head). Tests are conducted on helmets that have reached high temperatures (roughly 49 degrees Celsius/120 degrees Fahrenheit) and low temperatures (-18C/0F).
• Resist penetration, even at high and low temperatures.
• Withstand exposure to electricity, when applicable, without catching fire and while allowing only a marginal amount of electricity to "leak" through.

But in short, helmets built to ANSI standards—and selected according to OSHA rules—offer good protection against a range of threats and stand to make many construction site injuries far less severe.

Simple measures prove effective against the major risks

While the science and statistics of head injuries are complicated, preventing them isn't. And as construction site injuries continue to fall, commonsense steps regularly save lives. Workers and site supervisors can lower the risk of injury by always wearing helmets properly and ensuring their equipment is in good shape.

Most manufacturers recommend the following:

• Inspect hard hats regularly. Cracks, dents, and other visible damage can weaken the helmet's outer shell—and are a sign that it's time for a new model.
• Keep hard hats away from extreme temperatures, paints, and chemicals, and don’t store them in sunlight when they aren’t being used. Clean them as recommended by the manufacturer (typically, with soapy water).
• Replace the suspension annually or when it's visibly damaged—and replace the entire helmet when it reaches the limit of its service life. While there is no hard and fast expiration rule, many manufacturers print an expiration date on helmets and issue recommended service lives of 3-7 years. Generally, replacement is usually called for no more than five years from the point a hard hat is placed in service.

Want to learn more about helmets and head injuries? Check out more posts on the Hard Head Veterans blog, where we explore head injury survival stories, advancements in helmet technology, and the evolving science of brain injury.