A 24-year-old school bus driver is transporting students home after school. The weather is clear, the roadway dry. But the bus is speeding, and it veers off the road. As it careens out of control, it hits a tree that slices open the bus.

But this accident was in California,

. And the school bus in this crash was equipped with lap/shoulder belts for all the passengers, as required by California law.

ajc.com

Credit: Lois Norder

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Credit: Lois Norder

Most of the students - visible from video recordings from the bus - were wearing the belts, including two in a part of the bus torn open by the tree, according to

by the National Transportation Safety Board.

While four of the children and the driver suffered serious injuries in the 2014 crash, no one died. After running simulations, NTSB concluded that the students in the row closest to where the tree intruded would likely have suffered greater injuries, were it not for the lap/shoulder belts restraining them.

NTSB has recommended that all school buses be equipped with lap/shoulder belts, but California is the only state to require them. Florida, New Jersey and New York laws call only for seat belts, Governing magazine reported. Legislation has been introduced in a number of other states to require the restraints in new buses, but the measures have stalled for lack of funding.  Tennessee and Georgia are among states with no lap/seat belt requirements for school buses.

In the Chattanooga crash, at least five children died. The 24-year-old driver has been charged with vehicular homicide, reckless endangerment and reckless driving. He worked for a private company the school contracted with for bus drivers, the AJC's Jennifer Brett reported.

In the California crash, NTSB said that the bus driver, who had a history of high blood pressure, was unconscious when he lost control of the bus. The video recording showed he had had labored breathing, then slumped over and let go of the steering wheel.

He was charged with child abuse and endangerment in 2015.  California authorities said he had failed to disclose a medical condition that caused dizziness and blackouts.