The National Transportation Safety Board is recommending all new school buses have lap and shoulder seat belts.
It's the first time the board has made the recommendation, and it comes after the NTSB's investigation into two deadly school bus crashes in 2016.
A crash in Baltimore and another in Chattanooga, Tennessee, collectively killed 12 people and injured 37. The NTSB report found that in both cases, the drivers should not have been allowed behind the wheel of a school bus.
Forty-two states, Washington, D.C., and Puerto Rico don't require any seat belts on school buses. Four others require lap belts but not shoulder belts.
The NTSB also recommends the National Highway Traffic Safety Administration require all new school buses to be equipped with collision avoidance systems and automatic emergency braking technology.
The NTSB's recommendations are just that — recommendations. The board doesn't have any regulatory power, but its findings are usually followed by other transportation regulators.