Seat belts save lives. They support you if you're in a crash or when a vehicle stops suddenly. The force on seat belts can be as much as 20 times your weight - this is how hard you'd hit the inside of your vehicle without restraint.

Requirements for wearing seat belts

All modern cars in New Zealand must be fitted with seat belts and older vehicles may require webbing clamps to improve the 'hold' of their belts.

Specifically, in New Zealand the requirements are that:

  • front and back seats in all modern cars must be fitted with seat belts

  • if you sit in a seat with a seat belt you must wear the seat belt

  • all children aged under seven must be secured in an approved child restraint when travelling in cars or vans

  • children aged seven must use a child restraint if available. If not available, they must use a seat belt. If a seat belt is not available they must travel in the back seat

  • children aged between eight and 14 must use seat belts if available. If not available, they must travel in the back seat

  • people aged over 14 must wear seat belts where they are available.

There are additional requirements for seat belts in motorhomes.

What if I don't wear a seat belt?

If you're 15 years or over and drive or ride in a vehicle without wearing seat belt you can be fined.

If you're the driver you can be fined if you have a passenger aged under 15 riding in your vehicle without wearing a seat belt or child restraint.

New seat belt advances

Modern advances have improved the performance of, and protection offered by, seat belts. These features include:

  • webbing elasticity: the belt's webbing elongates during a crash to better cushion the wearer

  • retractors: these provide a secure fit, lock automatically during a crash and keep the belt out of the way when not in use. More sophisticated 'active control retractors' work with other in-car technologies to tighten the belt before a crash, and release it afterwards

  • pre-tensioner: this device removes any slack from a seat belt before it is 'loaded' with the force of your weight during a crash. The vehicle's restraint control module (an in-car computer that controls other protection systems) usually triggers it. Once triggered, pre-tensioners need replacing

  • load limiting: this technology matches the protection provided by the belt to the size and weight of the wearer. It works in conjunction with the pre-tensioner to either feed out more of the belt webbing, or slightly alter the way the retractor works

  • adaptive restraints: restraints that adapt to work differently depending on the size of the car's occupants or the type of accident.