Inclusive Crash Test Dummies: Rethinking Standards and Reference Models

The Challenge

In engineering design, the medium-sized male body (5'9"; 1.75 m; 171 lbs.; 78 kg) has been taken as the norm. It is no surprise then that men fitting this profile suffer the fewest injuries in automobile accidents (Carter et al., 2014; Ali & Mayrend, 2025).

When crash data is analyzed by sex, age, height, and weight, injury rates are higher among people who don’t fit the mid-sized male norm. Elderly drivers have high fatality rates per vehicle mile driven (Augenstein et al., 2003). Obese drivers also risk death and serious injury. And women are more likely than men to be injured in crashes. When considering the compounding interaction of these factors, elderly and elderly females and obese males suffer greater injury in crashes of equal severity than the “standard” male (Carter et al., 2014).

Gendered Innovation 1: Expanding Established Norms

Numerous efforts are underway to expand anthropomorphic test devices (crash test dummies) to represent greater diversity of human bodies, such as properly modeled females (Östh et al., 2016), children, the obese, and the elderly (Hu et al., 2012). Crash test dummies for children were developed in the 1990s (Humanetics, n.d.). for obese males in 2014, and for elderly females in 2017 (see Method: Rethinking Standards and Reference Models below).

Females: Women are involved in fewer severe automobile crashes overall, but when they are involved in a crash, they are more likely to sustain serious injuries, even when using seat belts. A 2019 study found that belt-restrained female drivers are 73 percent more likely to be severely injured or die in a frontal crash than men (Forman et al., 2019).

Crash test dummies designed to represent the 5th percentile female by height and weight (4'11'; 1.50 m; 108 lbs; 49 kg) were developed beginning in 1966 for high speed frontal impacts. These female dummies are scaled-down versions of the standard, mid-sized male and not modeled on female anatomy or physiology. The Hybrid III 5th percentile female developed in 1988, for example, is a scaled down male wearing a rubber jacket with breasts. These 5th percentile dummies represent a small occupant and do not capture the characteristic differences between the average female and male, such as: 1) geometry, e.g., shape of the torso and hip area; 2) muscle and ligament strength; 3) spinal alignment; 4) dynamic responses to trauma; 5) mass distribution of different body parts, making women more likely to be injured in crashes (Linder & Svedberg, 2019; Linder et al., 2013; Hu et al. 2012) (see Method: Analyzing Sex below). In the U.S. and European frontal tests, a 5th percentile female dummy is typically placed in the front passenger seat (apparently assuming that a small occupant does not drive (Linder & Svedberg, 2019; UNECE, 2025). When this 5th percentile dummy is moved to the driver’s seat, the risk of death for females decreases (Noh et al., 2022).

Researchers in Europe have developed a numerical model of a 50th percentile female for low severity rear impact testing—the EvaRID (Rear Impact Dummy)—and a physical prototype of a 50th percentile female dummy—the BioRID 50F (Linder et al, 2013; Linde & Svensson, 2019; Carlsson et al., 2021). Professor Astrid Linder, at the Swedish National Road and Transport Research Institute, has been instrumental in developing the SETs (Seat Evaluation Tools) that model both the geometries of an average male and average female to evaluate the safety of car seats in low severity rear impacts (Karemyr et al., 2022). The SETs could be integrated in the safety testing.

Obese People: The 50th percentile male dummy used in tests today represents the average height and weight of men in the late 1970s and early 1980s (Schneider et al., 1983). Today, the U.S. Centers for Disease Control classify almost 40 percent of Americans as obese (National Center for Health Statistics, 2024). People with high Body Mass Index (BMI) are more likely to suffer severe lower extremity and thorax injuries in crashes than people with low BMI (Carter et al., 2014). Data from field tests, cadaver tests, and computational studies have shown that increased body mass causes obese individuals to move forward in a frontal crash, increasing the risk of injury to the thorax and the knee, thigh, and hip complex (Hu et al., 2012). Obese males suffer greater injury in crashes of equal severity than the “standard” 50th percentile male (Carter et al., 2014); however, obese females are more likely to die in vehicle crashes than obese males (Rice & Zhu, 2014).

Elderly: Populations in many countries are aging. By 2030, over 25% of the populations in Europe and North American are expected to be over age 60 (United Nations, 2015). National U.S. data show that older people are more likely to experience serious injuries in almost every crash type (Carter et al., 2014). Older people have less dense bones and experience changes to the thorax region which increase injury risk. Older women are at the greatest risk of bone fracture (Hu et al., 2012).

Gendered Innovation 2: Pregnant Computer Crash Simulations

The advances discussed above systematically exclude pregnant bodies. Conventional seatbelts do not fit pregnant women properly, and motor vehicle crashes are the leading cause of fetal death related to maternal trauma (Weiss et al., 2001; Acar et al., 2018). Even a relatively minor crash at 56km/h (35 mph) can cause harm. With over 13 million women pregnant across the European Union and United States each year, the use of seatbelts during pregnancy is a major safety concern (Eurostat, 2011; Finer & Kost, 2011).

Seatbelts were first installed in automobiles in the 1950s, and their use became mandatory in the late 1980s and early 1990s. As early as 1967, the American Medical Association advocated the use of seatbelts by pregnant women (Committee, 1972). At that time, little laboratory research in seatbelt design addressed pregnant women, making it difficult to assess the comparative effectiveness of various seatbelt designs and other safety technologies, such as the airbag (Insurance Institute for Highway Safety, 1972). As seatbelt usage increased, injuries caused by lap belts began to raise concerns that seatbelts might be hazardous to a fetus even when the mother is not injured (Committee, 1972).

Current research suggests that pregnant women should use the 3-point seatbelt (McGwin et al., 2004), yet for many women, particularly those who carry low, 3-point seatbelts ride up on the pregnant belly. In a crash, this increases force transmission to the abdomen by three- or four-fold relative to the force transmitted when the belt is worn below the uterus‚ with a corresponding increased risk of fetal injury (Pearlman et al., 1996).

The development of pregnant crash test dummies and computer simulations have the potential to play a key role in increasing seatbelt safety for fetuses. A MAMA-2B (Maternal Anthropomorphic Measurement Apparatus, version 2B) was created in 1996 as a first step to modeling the pregnant body. In 2002, U.S. researchers adapted crash simulation software to model a 5th percentile dummy equipped with a virtual uterus, placenta, and amniotic fluid as well as uterosacral and round ligaments (Moorcroft, 2003). Using this computer model, validated by cadaver and real-world crash data, researchers modeled differences in outcomes between unbelted, belted, and improperly belted pregnant passengers. In 2008, researchers further improved this computer model by adding a realistic 38-week fetus (developed using ultrasound images) and modeling in utero fetal motion during impact (Acar et al., 2009).

In 2002, Volvo also developed a virtual pregnant crash dummy "Linda" in her 36th week of pregnancy. Other car companies and researchers have also used computer models and pregnant crash test dummies in safety testing (Hitosugi et al., 2018; Vladutiu & Weiss, 2012).

And research has begun to improve the 3-point seatbelt. One study recommends new materials—auxetic materials (image left)—for the lap belt to allow it to expand in order to lessen impact and to better keep the body in position (Panadero, 2020). Adding these auxetic properties to the current seatbelt design could enhance automobile safety for pregnant women and their fetuses.

Conclusions

Gendered Innovations have led to more inclusive standards for crash test dummies. In 2019, Volvo announced its E.V.A. (Equal Vehicles for All), an initiative that recognizes that virtual models and physical dummies need to represent a greater variety of body types. To this end, they are sharing their research and data from real-world crashes (Volvo, 2019). Academic and industry researchers are now ramping up efforts to expand crash test dummies to better model the human population. Women’s bodies, pregnant bodies, older bodies, and larger bodies, however, are still not standard or required in automobile safety tests.

Next Steps

1. The U.S. National Highway Traffic Safety Administration (NHTSA) currently requires safety testing using dummies, such as Hybrid III 50th male and Hybrid 5th female dummies for high-speed frontal testing, but not 95th percentile males or 50th percentile females, elderly females and males of different sizes, obese females and males, or pregnant women. The European New Car Assessment Programme (Euro NCAP) utilizes the same Hybrid III dummies as prescribed by the U.S. NHTSA (Euro NCAP, 2010; Euro NCAP, 2009; Linder, A., & Svedberg W., 2019; Linder, A., & Svensson, M., 2019). Governments should mandate vehicle safety testing using crash test dummies that represent the anatomical features and dynamic properties of both the 50th percentile female and male, and mandate the use of crash test dummies and simulation models, for both female and male obese, tall, and elderly bodies, and for specific conditions such as pregnancy.

The Furthering Advanced and Inclusive Research for Crash Tests Act (FAIR Crash Tests Act) was passed by the U.S. House and Senate in 2021 but has not been made into law. The Act ordered the Government Accountability Office (GAO) to evaluate NHTSA’s failure to use crash test dummies that represent the driving public, especially females, while assessing vehicle safety through its 5-star safety rating program. March 2023, the GAO delivered its report to Congress and the U.S. NHTSA (U.S. GAO, 2023). Various other acts have been introduced into Congree, but none has yet taken effect.

2. The traditional 3-point seatbelt can harm a fetus. Redesigning seatbelts to accommodate pregnancy should become a priority for automobile makers. Private developers have introduced supplementary devices to hold conventional lap belts in place‚ but these have not undergone rigorous government safety testing (Klinich, 2009). A better solution may be a redesign of the conventional 3-point seatbelt to provide greater safety for all passengers.