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Seat belt

technology Maturity 7-9 Next article →

A seat belt is a vital safety tool for vehicles.

Female driver buckling seatbelt
Female driver buckling seatbelt

It is designed to hold drivers and passengers in place. This prevents harmful movement during a sudden stop or a crash. When a vehicle is moving, everyone inside travels at that same speed. If the vehicle hits something and stops fast, people keep moving forward.

Female driver buckling seatbelt
Female driver buckling seatbelt

The seat belt applies an opposing force to hold people back. This keeps them from hitting the car's interior or the windshield. It also helps airbags work better by keeping people in the right position.

Seat belt BX
Seat belt BX

Most modern cars use a three-point seat belt. This system includes a lap belt and a shoulder harness. The shoulder harness is a strap that goes diagonally across the body.

Passenger Experience Week 2018, Hamburg (1X7A3813)
Passenger Experience Week 2018, Hamburg (1X7A3813)

This design is safer than older lap belts. Lap belts only go over the waist. In the past, lap belts could cause serious spine injuries. This was sometimes called "seat belt syndrome." Because of this, new rules now require three-point belts in most seating positions.

Seat belt BX
Seat belt BX

Many people helped develop these safety tools over a long time. George Cayley invented early belts for his glider in the mid-19th century. In 1949, Nash was the first American car maker to offer them. However, many buyers did not want them at that time. Later, Nils Bohlin developed the modern three-point belt for Volvo.

Seatbelt testing apparatus
Seatbelt testing apparatus

He proved it worked by studying 28,000 accidents in Sweden. His study showed that belted people were much safer during crashes. In 1966, the United States passed laws to set safety standards for all cars.

The fabric part of a seat belt is called webbing.

Female driver buckling seatbelt
Female driver buckling seatbelt

This webbing is very strong so it does not tear easily. Most modern belts use 100% polyester instead of nylon. Polyester is better because it does not stretch as much. It also resists damage from the sun's UV rays. The webbing is usually 46 or 48 mm wide. It uses a special weaving pattern to make the threads very dense. This helps the belt stay reliable during a high-speed collision.

Seat belts are used in many different ways today.

In airplanes, two-point lap belts are very common. These keep passengers in their seats during bumpy turbulence. In cars, the three-point belt is the standard for safety. Using these belts saves a huge number of lives. In the United States, they reduce serious injuries and deaths by about half.

Lives Saved by Safety Belts and Air Bags, NHTSA, DOT
Lives Saved by Safety Belts and Air Bags, NHTSA, DOT

They are one of the most important ways to stay safe on the road.

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🖼️ Images & Media (16)
File:Female driver buckling seatbelt.jpg
Female driver buckling seatbelt.jpg
File:Lives Saved by Safety Belts and Air Bags, NHTSA, DOT.svg
Lives Saved by Safety Belts and Air Bags,...
File:Aircraft Safety Belt.png
Aircraft Safety Belt.png
File:Airplane seat belt 2.jpg
Airplane seat belt 2.jpg
File:Passenger Experience Week 2018, Hamburg (1X7A3812).jpg
Passenger Experience Week 2018, Hamburg...
File:Passenger Experience Week 2018, Hamburg (1X7A3813).jpg
Passenger Experience Week 2018, Hamburg...
File:Seat belt BX.jpg
Seat belt BX.jpg
File:Seatbelt.jpg
Seatbelt.jpg
File:Bucket seat with Schroth six-point harness in a 2010 Porsche 997 GT3 RS 3.8.jpg
Bucket seat with Schroth six-point...
File:Intertial-reel.jpg
Intertial-reel.jpg
File:Gurtstraffer.gif
Gurtstraffer.gif
File:1990 Honda Civic DX interior.JPG
1990 Honda Civic DX interior.JPG

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