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Size Differences

While safety is always a shared responsibility for all drivers, riders and pedestrians who share our streets and roads; driving, cycling or walking around large trucks and buses requires extra care.

Many road users don’t realize the significance of mass and size when it comes to traffic safety. A tailgating crash between two passenger vehicles may result in a fender bender. However, a similar crash between a passenger vehicle and a large truck or bus may have greater consequences. 

Size differences greatly affect how truck and bus drivers operate – and all road users should be aware of their unique safety challenges to help keep everyone on our roads safe. 

A Massive Size Difference

Image saying trucks and buses have large size differences when compared to cars and other road users

  • Trucks are often 20 to 30 times heavier than passenger vehicles.
  • The huge mass of a truck or bus increases the risk of more severe crash damage, injuries and fatalities.
  • Large size and weight increases driving challenges, including acceleration, braking and handling (maneuverability).
  • Trucks and buses accelerate more slowly uphill and may gain speed quickly downhill.

Height - and Heightened Safety Considerations

  • Tall vehicles have a higher center of gravity, roll over more easily than smaller vehicles and must go much slower on curves and ramps.
  • Large vehicles generate wind gusts that can push smaller vehicles into other lanes.
  • Smaller vehicles can be pushed or pulled under a commercial vehicle with high ground clearance.
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