The American government needs to get much, much, much smarter about cycling safety, the National Transportation Safety Board concluded this week, during its first evaluation of the issue in almost half a century. The feds should help cities improve infrastructure for people who bike, to prevent fatal collisions with cars, the NTSB panel found. Regulators should require that vehicles come with cyclist-friendly safety features like brighter headlights. Most controversially, the panel said that all states should require all cyclists to wear helmets—a suggestion that has long rankled bicycle activists.

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The investigation by the NTSB, which has no regulatory power, comes at a delicate time. More people are using bikes to get around American cities than in recent memory: According to census data, 837,000 Americans rode to work in 2017, marking a 43 percent rise since 2000. But from 2017 to 2018, while road deaths declined by 2.4 percent, cyclist fatalities jumped by 6.7 percent. In total, 857 bicyclists died in crashes with motor vehicles.

“If we do not improve roadway infrastructure for bicyclists, bicyclists will die who otherwise would not,” Robert Sumwalt, the NTSB chair, said during a meeting convened to review the research in Washington, DC, this week. “If we do not enhance bicyclist conspicuity, likewise, additional bicyclists will die. If we do not act to mitigate head injury for more bicyclists, additional bicyclists will die.”

The NTSB’s full report on bicycle safety will be released later this month, but the top-line results reveal some unsettling trends. Investigators found that 25 percent of all deadly bicyclist collisions happened mid-block, when a driver overtook a cyclist. These collisions are more likely to be fatal because cars are more likely to be traveling quickly between intersections. In fact, NTSB investigators’ research suggests that a cyclist hit by a car on a road with a posted speed limit of 30 to 35 mph is 65 percent more likely to die than one hit on a road with a limit of 25 mph or below.

But the report also motioned toward some easy fixes—well, as easy as building new infrastructure in cities is nowadays. Protected lanes separating cyclists from vehicle traffic would “eliminate” those mid-block crashes, the NTSB said. “Road diets,” which limit space for cars and provide dedicated spaces for bicycles, would cut crashes by somewhere between 19 and 47 percent.

Transportation engineers have known about these infrastructure safety fixes for decades. But only recently have some been empowered to build these bicycle-centered safety features into roads—and to fund them too. Still, “more conservative engineers who aren’t willing to accept road designs from other jurisdictions, or those created in the last several years” can be wary of building biking- or walking-friendly street designs into the roadscape, says Ken McLeod, the policy director of the advocacy group American League of Bicyclists. Broader support of bicycle-safe designs from the federal government might give even the most car-centered engineers—and those who write state- or nationwide street design guides—a bit of a push.

NTSB researchers also emphasized that cyclists wearing helmets are less likely to die in crashes. In fact, 79 percent of those who died in incidents between 2010 and 2017 were not wearing a helmet. (That stat only accounts for those whose “helmet use” status is known—it’s not always noted in accident reports.) And the NTSB’s research review indicated that mandatory helmet laws increased helmet use by somewhere between 10 and 84 percent. And so the panel wants every state to require anyone riding a bicycle to wear an age-appropriate helmet.