Refraction Education : NRMA Car Safety (Years 9-10)
24 THE ROAD SAFETY TOTAL LEARNING RESOURCE • YEARS 9–10 Anti-lock brake system (ABS) This is one of several braking technologies that reduce the chances of a collision happening, as well as the severity of the collision. Without ABS the sudden braking needed in an emergency can lock the wheels – and steering – causing the driver to lose control of the car. Crumple zones Once a crash happens, crumple zones at each end of the car (front and rear) absorb the kinetic energy, collapsing in a controlled way and slowing the impact and reducing forces. In doing so, they also minimise the impact on the reinforced metal safety cell containing the passengers. In some cars the heavy engine block detaches from the front of the car and slides under the cell, reducing the impact even further. Side-impact bars These strengthen the car and protect it against side-on collisions. The steering wheel column and brake pedals are designed to collapse away from the driver during a crash, reducing the chances of impact. Windscreen of laminated glass This provides a further barrier against objects that might come into contact with a car. It is made up of two layers of glass bonded together with clear plastic; once broken, the plastic keeps the window in one piece. Seatbelts These are crucial; they hold passengers in their seats and reduce the chances of them hitting the inside of the car or being thrown outside the car. Seatbelts must sit across hard bones – collarbones and hipbones. Slipping your seatbelt under your arm if it is rubbing against your neck will means ribs and soft tissues will be damaged in a crash. Use the seatbelt adjustor to lower the seatbelt. Also important is how the seatbelts are designed to stretch during a crash. This slows the deceleration of the passengers, reducing the forces acting on them. A device called a pretensioner reduces slack in the belt when it senses a crash, holding passengers more securely and spreading forces more evenly across their waists and chests. Remember to replace seatbelts after a crash, as they can only be stretched once. Airbags These provide added protection, by inflating when a crash occurs. Like seatbelts, they slow the impact and reduce the force. They also spread the force over a larger area than the seatbelt, reducing the impact on the passengers even further. Airbags and seatbelts are designed to work together – just because you have airbags it doesn’t mean you don’t need seatbelts. Head restraints also prevent passengers’ heads from snapping backwards in rear-end crashes.
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