The seat belt: all the information you need to correctly evaluate it

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Although passive safety in cars has advanced significantly over the past few decades, the seat belt remains the most crucial safeguard for passengers. Discover all the information.

The seat belt has been saving lives for many years because, despite significant advancements in car technology, it remains the most reliable passive safety system for drivers and passengers.


The seat belt, whose effectiveness cuts the chance of death in an accident by half, is the item that has saved and continues to save the most lives on the road, according to the data.

Additionally, because both devices are made to function together, the airbag is ineffective if the seat belt is not worn in addition to it. Similar to neck and head restraints, head restraints are crucial.

The Volvo Amazon used seat belts as standard equipment for the first time in a production vehicle.

When a seat belt is used, the risk of mortality and severe brain injuries is 90% lower in frontal collisions. It also substantially lowers the chance of fractures, wounds, and other injuries by 75%.

Rear-end crashes had a 50% lower chance of fatalities or serious injuries. Let’s discuss seat belts now.


Like many other automotive innovations, the earliest seat belts originated in the aviation industry. Particularly throughout the 1930s.

Preston Tucker, an American entrepreneur, and car designer introduced the seat belt as one of the optional features on the Tucker Torpedo, a four-door sedan introduced in 1948, of which 50 units were made in the late 1940s.

A significant automobile in automotive history is the Volvo Amazon.

The seat belt was abandoned after Robert McNamara’s business was shut down over fraud allegations. Still, Ford revived it in 1956 with SafeGuard, a safety package for their cars.

Three years later, the Volvo Amazon, which had a Nils Bohlin-designed three-point seat belt as standard equipment, became the first production vehicle to do so.

Soon after, the Swedish company published the patent to make it a standard safety feature in all automobiles.

Why is a seatbelt necessary?

Is it easy to answer this question? In a collision or accident, the seat belt reduces injuries to its users. It accomplishes the following to this end:

By cushioning the body’s deceleration, it prevents more serious damage.

It prevents or lessens the force with which the passenger strikes other car parts like the steering wheel, dashboard, or seats.

It avoids throwing passengers from the car in the case of a rollover or hard impact.

Passengers have seat belts to shed their kinetic energy, just as the automobile has deformable structures to lose it’s in the event of a crash.

The belt is designed to stretch, not because its fibers are elastic, but because they are woven to lose width and gain length to prevent the wearer from suffering significant injuries.

The most significant force a belt must bear without breaks is 1,200 kg. However, manufacturers mount straps that can endure up to 3,000 kg.

However, the seat belt’s most crucial feature is not how much force it can bear (because materials that increase its strength might be used) but rather how much deformation it can withstand.

This is only at 30 km/h, mind you.

Crash tests at 50 km/h were performed in the lab on dummies that were 1.74 m tall and weighed 76 kg to determine this.

It has been demonstrated that a body of this weight may exert a force of up to 1,000 kg on the belt.

In these circumstances, a particularly violent deceleration causes the belt to stretch, causing the body to move forward by a distance of 25 cm.

Seat belt components

The functionality of a seat belt is dependent on three primary systems in addition to the features of the fabric from which it is made:

Load limiter system: When the strain on the chest or pelvis exceeds a specified level, this device permits an additional 5 to 7 cm length. This lessens or prevents whiplash and internal harm.

When a particular force is applied, or the belt’s inclination is insufficient, the angular locking system prevents the belt from falling out of its housing. The latter is advantageous in case of a tip-over.

Belt sensitivity locking system: the mechanism locks the belt to keep it from coming out when the occupant jerks forward suddenly, as usually happens in frontal accidents.

Seat belt varieties

There are many seat belt variations because of how much they have evolved. From the most basic lap belts to competitive belts with five points of fastening.

The lap or abdominal belt is fastened around the passenger’s hips at two locations. As it separates the lumbar spine and results in paralysis, it is employed in flights and has previously been abandoned in automobiles.

The most popular belt has three anchoring points, one above the shoulder and a third anchorage point for a lap belt.

The risk of slipping and moving the body forward is essentially eliminated since they support the thorax and abdomen.

Due to the abdominal belt’s poor efficiency, it is no longer in use.

Five-point harnesses: These are typically used in competition or child restraint systems (CRS), and they have four points with straps that are fastened to the shoulders of each user, plus a fifth point that is attached between the legs.

To prevent whiplash in children, it is advised to use it for as long as possible in the opposite direction from the direction of travel.

The HANS is used in conjunction with it during competition to prevent forward head movement.

Except for the fifth point, which is positioned between the knees, a four-point belt is similar to a harness.

The rear-seat seatbelt and the submarine effect

Seat belts are also necessary in the back seats because, in the event of a frontal collision, for instance, there is a potential for an occupant of these seats to fatally strike a front passenger up to an eightfold greater likelihood.

Without seat belts, rear passengers are thrown forward at 80 km/h with force comparable to that of a 1,200 kg ball hitting a wall at 10 km/h, which has the potential to kill or badly hurt individuals in the front seats as well as the back passengers themselves.

Yes, it is also required in the back seats; quit making excuses and put it on!

The findings indicate that they are used less frequently in the back seats than in the front. If we consider the averages for 2017 to 2019, 25% of people who died in passenger vehicles did not wear a seat belt while driving, but this number rises to 31% for people who were killed while riding in the backseat.

On the other hand, one of the most significant risks of improper seat belt use is the submarine effect. The body presses against the seat and slides beneath the belt’s lap band due to the belt’s loosening the “submarine effect.”

This creates significant issues for the integrity of the occupant because it increases the possibility of hitting the dashboard or steering wheel, pressing against the abdomen, and raising the possibility of internal injuries.

Finally, when sliding causes contact with the pedals or other objects in the passenger compartment’s lower section, it might result in limb fractures.

For all of the reasons above, it’s crucial always to buckle your seatbelt correctly and in the proper position.

Myths and stereotypes regarding seat belts

The seat belt is already ingrained in the habits and mindset of the driver and passengers of a car, but for a sizeable portion of individuals, it is still a contentious issue.

We will examine some of the incorrect arguments made by many of them why they are not helpful.

My automobile has a lot of safety features. None of these substitutes the seat belt; they are all complementary to one another.

I’m not going to get into any mishaps. Both are avoiding one’s forgetfulness or mistakes and controlling the actions of other road users possible.

Seatbelts serve no purpose. Data on accidents show the opposite.

The WHO estimates that this only occurs in every million cases.

In a city, it is not necessary. A head-on accident that hits the front glass at 40 km/h can be lethal. A 70 kg human becomes a 3000 kg missile at 50 km/h.

On brief trips, nothing happens. Statistics show that they are the most harmful.

The percentage of lives saved by seat belts decreases as vehicle speed increases.

Without it, passengers in the back will sustain significant injuries or death, while those in the front seats will perish during impact.

Throwing people out of cars saves a lot of lives. In this scenario, the likelihood of a fatality and significant spinal cord damage both increase by 1300% and 300%, respectively.

The belt feels uneasy. The pain of the injuries, the guilt of having murdered or gravely injured someone, or one’s own death are more uncomfortable.

Do you want to know if you should use a seat belt while pregnant or how to do so? Do you know who pays the fee when a passenger is not buckled up? Remember to read our articles on the subject as well.

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