In 1958, an accountant from the US state of Ohio named Richard Wayman hatched an idea to improve the behaviour of young motorists by presenting – in blood-soaked colour – the sickening outcomes of bad driving.

Armed with a police-band radio and a handheld movie camera, the amateur documentarian prowled the night in search of vehicular carnage. He found plenty. His called his first highway safety film Signal 30, the Ohio State Highway Patrol’s radio code for a fatal wreck. This shaky, 28-minute film would forever change the public’s perception of automotive safety.

The highway safety film arrived as a subgenre of a broader cultural phenomenon in the US: the social guidance film. During the two decades following the end of World War II, these quaintly stern short subjects were intended to nudge adolescents in the right direction on a variety of topics – hygiene, manners, parental relations, friendship, dating and, of course, sex. In darkened classrooms across the country, American grade- and high-schoolers received these carefully measured doses of social guidance via rattling 16mm projectors – many of them decommissioned machines previously used by the US government to present wartime training films to soldiers and sailors.

With Signal 30, the classroom education film took a page from the US Army playbook: the scare tactic. Like the short military films that aimed to keep GIs on the straight and narrow by highlighting the shame and agony of syphilis and gonorrhea, the highway safety film aimed to unnerve adolescent driver-trainees with nightmarish images of fresh car wrecks and their victims.

Amid wooden recitations from Ohio State troopers and a narrator’s dark commentary (“Now comes the nauseating task of removing the shattered hulk of a life that had been lived so little.”), Signal 30 presents actual footage from accident scenes. “We’re cruel, cold and harsh, you say?” asks the narrator. “You shouldn’t be made to see and hear this? How could we give a better lesson on carelessness?” The film is just long enough to occupy a single driver’s education classroom meeting, with time left over for shaken contemplation.

Unsettling viewing Ready to get up close with the driver's ed scare film? Director Bret Wood’s documentary Hell’s Highway stands as the definitive guide to the driver’s ed scare film. The DVD edition, available at www.kinolorber.com, includes clips from more than a dozen shorts and three full-length films. Film historian and archivist Rick Prelinger’s extensive online repository of ephemera (www.archive.org) features Signal 30 in its digital stacks, and many subsequent driver’s ed films can be found on YouTube. Warning: These films are not for the faint of heart. For a broader (and much lighter) look at the social guidance film as a cultural phenomenon, see Ken Smith’s excellent book, Mental Hygiene: Classroom Films, 1945-1970. — MP

To be fair, the 1950s – the golden age of the classroom education film – produced a handful of bloodless short dramas devoted to safe driving, of which the most notable was Last Date (1950), starring a young Dick York, who went on to play Darrin Stephens in the 1960s television comedy Bewitched. And it was a Canadian film from 1958, Safety or Slaughter, that is generally acknowledged to be the first educational film to make use of actual footage from accident scenes. But Wayman’s film is the genre’s seminal title, inspiring not only two sequels – 1961’s decidedly more gruesome Mechanized Death and 1963’s Wheels of Tragedy – but a horde of knockoffs, pictures with grim titles like Highways of Agony and Red Asphalt. And as the era of the highway safety cinema wore on, filmmakers one-upped each other with an ever more ghastly cavalcade of gore – drivers separated from limbs or heads, shredded by tarmac, filleted by ragged sheet metal or skewered on steering columns. Signal 30 is, far and away, the tamest entry in the genre – almost quaint when compared with a later film (1971’s ghastly Death on the Highway, in particular) – but it is safe to assume that no one who sat through Richard Wayman’s debut effort soon forgot its message.

In terms of vehicular carnage, the ‘60s proved to be the busiest decade since the invention of the passenger car. In the US, big V8 engines had democratised speed; huge power became affordable enough for mainstream buyers. But advances in horsepower dramatically – and dangerously – outpaced advances in braking, steering and suspension. And occupant protection? Barely a consideration, giving Richard Wayman and his imitators more than enough raw material.

In 1965, US political activist Ralph Nader published his seminal book on the auto industry’s willful safety failings, Unsafe at Any Speed. The volume, which included an entire chapter on the “one-car accident” that was the Chevrolet Corvair, highlighted what Nader believed to be US automakers’ disinterest in such potentially life-saving features as seat belts and collapsible steering columns. The book caused a stir in Detroit and Washington, but its general readership was small, relative to the body of licensed drivers, and its argument, while valid, was largely academic. Congressional hearings cannot hope to compete with smoldering wrecks. The highway safety film was visceral, relatable, painful.

It may be a stretch to assert that Signal 30 and later films if its ilk directly influenced the introduction of automotive safety features. But there is no denying that some of the motor industry’s most important safety advances came during the heyday of the driver’s ed film. The collapsible steering column, for instance: Although patents for impact-absorbing steering columns date to the 1930s, it wasn’t until 1967, in response to coming government legislation, that General Motors and Chrysler made the feature standard on all models; Ford followed in 1968. Seat belts, too: Although US carmaker Nash offered lap belts as options as far back as 1949, it wasn’t until the enactment of federal legislation in 1968 that belts became required equipment for all cars sold in the US.

In the 2003 documentary Hell’s Highway: The True Story of Highway Safety Films, John Butler, the former chief of police in Richard Wayman’s hometown of Mansfield, Ohio, spoke of the filmmaker in heroic terms – the saviour of thousands of lives. “He lobbied Congress,” Butler says. “His people testified before Congress and they passed a seat belt law. When you fasten that seat belt today, that’s because of old Richie Wayman.”

If you would like to comment on this story or anything else you have seen on BBC Autos, head over to our Facebook page or message us on Twitter.