Peters rode a packed school bus to Morrisville Elementary School, among the first schools in the country to equip some of its new buses with seat belts, then said she wants to increase the height of seat backs on all school buses from 20 inches to 24 inches to help protect children during accidents.
Peters also proposed a new requirement for short school buses - the style more prone to rollover accidents - to begin using shoulder straps. For longer buses, however, she instead proposed allowing states the option of using federal highway safety funds to retrofit them with seat belts.
She promised no new money to cover those costs.
"We want school districts to make that decision," said Peters, noting that smaller buses don't carry as many students. "They'll make the decision about how to protect the most children within their areas."
A new bus with seat belts costs about $10,000 more than one without the devices, said Derek Graham, a transportation services official for North Carolina schools. North Carolina puts about 800 new buses on the road each year, meaning the seat belt buses would cost the state an additional $8 million each year.
The country has about 474,000 school buses, Peters said.
Schools have increasingly gone to higher seat backs. Peters said that taller children are prone to flying over the seats if the backs are too short.
"It's like putting an egg in an egg carton," she told Sarah Omwenga, a 7-year-old who sat next to Peters on her ride to Morrisville school.
They buckled up in the new bus retrofitted with tall seat backs.
Small buses, which already use lap belts, will have three years to begin equipping new buses with the shoulder style. School districts will have to begin using the taller seat backs on new buses one year after the rules are approved.
The department will decide whether to adopt the proposal after a 60-day public comment period.