Although he was testing the effects of supersonic speeds on the human body, as one might experience in an airplane crash, his findings eventually influenced his advocacy for the most fundamental motor vehicle safety feature around today: the seat belt. Stapp was also involved in some of the first tests of vehicle airbags.
Stapp was present in 1966 when President Lyndon B. Johnson signed the National Traffic and Motor Vehicle Safety Act and the Highway Safety Act, which required seat belts in all new cars. Years later, in 1984 New York became the first state to pass a law requiring seat belt use in passenger cars. Still, as recently as 2003, seat belt use was not strictly enforced in all 50 states, prompting the “Click It or Ticket” campaign to go nationwide, encouraging seat belt enforcement.
But safety features like seat belts can only go so far in protecting passengers when vehicles are traveling at higher speeds. Infrastructure such as highway guardrails have been in use for decades. But earlier models had a tendency to create larger problems for drivers, as some metal guardrails had a tendency to impale vehicles upon impact, while other designs avoided that problem, but created conditions that would vault or roll vehicles.
Dr. Dean Sicking, a professor at the University of Alabama at Birmingham and a recipient of the National Medal of Technology and Innovation, is credited with designing some of the most widely used guardrail systems that are in place today. In the 1990s, Sicking designed guardrail end terminals that would safely absorb the energy from the impact of a vehicle, while curling the metal from the guardrail away from the vehicle as it continues to slide along, ideally bringing the car to a controlled stop.
“The flattening and curling absorbed energy to slow the car down,” Sicking says. “It prevented the spearing because the front was designed so it became locked into the front of the car, and it didn’t slide sideways, or up and down.”
Dean Sicking accepting the 2005 National Medal of Technology and Innovation from President George W. Bush
Typically guardrails are placed on stretches of road or highway that have more severe dangers, such as steep embankments or slopes, thick patches of trees, or other objects that might present a hazard for drivers, but could be difficult to correct or remove. In those cases, striking a guardrail might have less severe consequences, according to the Federal Highway Administration.
“They can make roads safer and lessen the severity of crashes. The guardrail can operate to deflect a vehicle back to the roadway, slow the vehicle down to a complete stop, or, in certain circumstances, slow the vehicle down and then let it proceed past the guardrail,” the FHWA said in a 2014 document. “This is not to say that guardrails can completely protect against the countless situations drivers may find themselves in. The size and speed of the vehicle can affect guardrail performance. So can the vehicle’s orientation when it strikes the guardrail. There are many other factors. Transportation engineers, however, carefully weigh the placement of guardrails so that for most drivers in most conditions the barriers work – and work well.”
For Sicking, the work is never over. He says he and his colleagues are currently developing improvements to guardrail systems that he believes could prevent more than 50 percent of the current fatalities involved with guardrail terminals and crash cushions.