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Why Are There No Crash Test Dummies That Represent Average Women?

Most vehicle-crash safety tests use a female dummy that's 4-foot-11 and 108 pounds. But she's still based on the male body type, and she isn't put in the driver's seat for front-impact starred-safety tests.

By Sophie Putka
Feb 16, 2021 8:00 PM
shutterstock 275530472 (1)
A representation of a crash test dummy. (Credit: Current Value/Shutterstock)


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Hybrid-III 5F has no clothes and no hair — only a pair of plain black shoes that look like the type of clogs favored by line cooks and doctors. On her face is a half-smile and an expression of mild contentment. This model of aluminum and steel, and her smaller cousin, SID-IIs, are the crash-test dummies usually used to represent females in car-safety testing.

She and SID-IIs reflect the 5th percentile in height of women from more than 30 years ago, when they were developed. Only 5 percent of women will be shorter than this dummy. At a petite 4-foot-11 and 108 pounds, Hybrid-III 5F is a little lighter than an average 12-year-old girl today. SID-IIs has no arms and weighs 97 pounds.

Today, the average American woman is 5-foot-4 and weighs more than 170 pounds, according to the most recent data. Major safety rating systems used around the world don’t use an updated representation of an average female in their tests for car safety. In fact, they don’t even put a female dummy in the drivers’ seat for most crash tests in the US. This has major implications for the safety of women driving cars — and it’s likely many women don’t even know that the car they’re driving hasn’t been crash tested with a dummy that resembles them.  

Better female models in crash tests are being called for, and some are on the way. But the process of making cars safer for female drivers is complicated.

Except for minor differences, most car requirements around the world call for similar test procedures — but none of them use a dummy that represents an average female. “We need a reality check,” says Astrid Linder, an engineer, researcher, director of traffic safety at Swedish National Road and Transport Research Institute, and a professor at Chalmers University. Linder has been a leader in the push for accurate female crash-test modeling worldwide for years. “And that reality consists of females and males — therefore we need representations of females and males in our tests.”

More Women Hurt in Similar Crashes

More than 257 million adults are of driving age in the U.S. Of those, slightly more women hold driver's licenses than men. In 2018 alone, there were 36,560 motor vehicle crash deaths in the U.S., more than from HIV or the flu

Because men drive more miles and engage in riskier driving — speeding, not wearing a seatbelt, driving drunk — more men than women die in car crashes overall. But when you compare similar car accidents with belted occupants of about the same age, height, BMI and vehicle year, women are 73 percent more likely to be seriously injured in frontal car accidents, according to a study from the Center for Applied Biomechanics at the University of Virginia in 2019

“We've known for decades that women are more likely to be injured and killed in crashes [of the same severity],” says Jessica Jermakian, vice president of vehicle research at the Insurance Institute for Highway Safety in Virginia. “And a lot of that has to do with their vehicle choices and the types of crashes they get in.”

Women tend to choose smaller and lighter cars than men do, according to a new study released last week by the IIHS. They're also more likely than men to be driving the struck vehicle in side-impact and front-into-rear crashes. But the discrepancy can’t be explained entirely by these factors, Jermakian says. The answer lies in car safety.

Drivers and automakers rely on car safety ratings issued by two major agencies that perform crash tests: the U.S. Department of Transportation’s National Highway Traffic Safety Administration (NHTSA) and the auto insurer-funded Insurance Institute for Highway Safety (IIHS), where Jermakian works. How they rate cars in their crash simulations influences how car manufacturers design cars to protect occupants.

Both NHTSA and the IIHS use male crash-test dummies that are 5-foot-9 — which falls in the 50th percentile for height — in the drivers’ seat for starred safety-rating tests. The 50th percentile means that roughly half of men are taller than this and half are shorter.

The dummies used in frontal-impact tests weigh nearly 30 pounds less than today’s average American male. Neither agency puts female dummies in the driver's seat for frontal-impact safety-rating crash tests, which are the most fatal crashes. Side-impact crash tests do include female dummies in the driver's seat.

The original Hybrid III family was expanded to include a 95th percentile male, a 5th percentile female (that is still based on the male body shape), a 3-year-old and 6-year-old. (Credit: Public Domain/Wikimedia Commons)

Since 2003, the NHTSA has placed 5th-percentile female crash-test dummies in the driver's seat during compliance testing, which tests whether cars meet the government’s minimum safety standards. But unlike the starred safety ratings, the public doesn't have access to the compliance test results.

And it's important to remember that neither agency uses a female crash-test dummy representative of average, modern women. That’s because a crash-test dummy like this doesn’t even exist.

Why Crash Tests Are the Way They Are

Jermakian explained that a history of male bias precedes today’s crash test standards, beginning with Sierra Sam, the first crash-test dummy. Sam was developed in the 1940s for the U.S. Air Force to help protect pilots, and was in line with the body norms of the day. Sam represented a person most likely to end up in the cockpit of a plane: an adult male. 

Dummies designed for vehicle crash tests evolved from Sam. The VIP series, called Hybrid I, standardized the 50th-percentile male and was modeled after an average man in the 1970s. Hybrid II included adjustments to spine, shoulder and knee anatomy. A few generations of crash-test dummies later, the 5-foot-9, 171-pound male is still the driver in most NHTSA and IIHS front-impact safety-rating crash tests. A female dummy was eventually added to some tests, but never was representative of average height and weight. “I wasn't there, but I assume the reason why we started with male dummies is related to the same male bias we see in science and in many fields,” says Jermakian.

With the disparity in injuries between men and women, it might seem like a no-brainer to simply make a female crash-test dummy that reflects the average height and weight of women today and put her in the driver’s seat during tests. But some experts say they’re not sure that would fix the problem.

Plus, crash-test dummies don’t just grow on trees.

“Dummies, because you have to design and build them and they [require] many years and millions of dollars to develop — there just aren't that many of them out there,” says Jason Forman, a principal scientist at the University of Virginia’s Center for Applied Biomechanics and lead author of the 2019 study that showed females were 73 percent more likely to be severely injured in crashes. Indeed, a new crash-test dummy can cost upward of a million dollars

When asked why there’s no average female used, a representative from the NHTSA wrote in an email to Discover that “the agency uses both the 50th-percentile male and 5th-percentile female crash test dummies in various crash tests ... to ensure that vehicle manufacturers design and produce vehicles for crash protection not only for a wide range of occupant sizes but also for targeted occupants at risk when involved in a crash.” 

If you build a car that protects both the largest and smallest occupants, NHTSA, IIHS and others reason, the different sizes and weights in between are also protected. NHTSA also says they found that smaller women, not average ones, were more likely to be injured in frontal crashes. 

Still, a 5th-percentile female dummy "represents a 12 to 13-year-old,” Linder says. “It's good to use the small occupant when you want to ensure that that you have covered a range, but it isn't in any way representing the female part of the population.”

Turns out, the 50th- percentile male Hybrid III dummy is not necessarily an accurate representation of today’s average male either, who is about the same height but roughly 27 pounds heavier. And since the female Hybrid III 5F is just a scaled-down model of him, none of the dummies widely used for safety rating tests reflect the many other physiological differences between male and female bodies: different shapes, weight distribution, muscle mass, and so on. 

“We know that from an injury prevention perspective, it's not only about weight and height,” says Linder. “Everybody knows the difference between Barbie and Action Man. And those are characteristic differences between females and males that we all recognize.”

What’s Being Done About It

New efforts to improve safety for women have been underway for years, but there’s still no female dummy that represents their bodies. A new line of crash-test dummies called THOR have been available for six to 10 years, but have yet to be officially adopted by NHTSA or IIHS safety rating systems. That’s according to Chris O’Connor, the president and CEO of Humanetics, the company producing THOR and other crash-test dummies. They are truer to male and female human bodies in shape and have as many as 100 more sensors to collect data than the Hybrid III family. The female version actually has a female-shaped pelvis bone and breasts — but is still 5th percentile in size.

Linder has worked with other European researchers to develop EvaRID, the first average female model. EvaRID is a virtual model of a dummy, and she’s meant for low-severity, rear-impact crash testing to prevent whiplash, another disproportionate problem for female drivers. Virtual modeling doesn’t always yield results that are as concrete as physical tests, but it allows much more flexibility in simulating car crashes with varying body types.

EvaRID weighs as much as an average female, has corresponding weight distribution, geometry, and even an approximation of muscle strength in the neck to model whiplash injuries. Linder says that because this model wasn’t as widely used as she had hoped, she is working on another initiative to develop a virtual model of actual humans rather than dummies. A version of the new ViVA+ virtual average female model is open source and will be available this year. Linder says there has been broad interest from around the world. 

Jermakian at IIHS, who co-authored the new study on injury risk for males and females out last week, found that while safety improvements have made cars safer for everyone, women are still “substantially” more likely to suffer injuries to their lower extremities like legs and feet. “That is a factor we incorporate into our rating program, but it's not the biggest factor we incorporate. So that's something we need to take a closer look at,” Jermakian says. 

Some experts say efforts come down to political will. O’Connor, whose company makes Hybrid III and THOR models, says that although the technology already exists, it’s another thing to get automakers and regulators to adopt it quickly. “There's no reason that it should take this long, quite frankly,” he says. “And, you know, a lot of it is politics. You have big corporations who don't want change, who don't want to be forced to change.” 

To Linder, however, it’s quite simple: “What should already have happened, and what should happen very soon, is that society is clear that men and women are equally important.”

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