Alberta bus rollover leaves 3 in critical condition

“Some of the passengers did sustain critical injuries and had to be extricated from the bus”

Three people are in critical condition and 26 others are in hospital after a Greyhound bus rolled in northwestern Alberta early Tuesday morning, trapping some beneath it, officials said. via CBC News

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it is mandatory to wear seat belts, why is there no seat belts on school buses, greyhound buses, bus services in cities or towns. what makes them exempt that the passengers don't wear a seat belt, wouldn't have there been less injuries in this bus crash?