Seat belts are an important safety component in vehicles, saving countless lives and reducing injuries in car accidents. Let’s take a look at the history of seat belts, how they work, and their significant impact on driver and passenger safety.
A Brief History of Seat Belts
Using restraints to protect vehicle occupants dates back to the 1800s when British engineer Sir George Cayley created the first restraints for safety in his experimental gliders. By the 1930s, seat belts were used in airplanes and race cars, although they were not yet common in passenger vehicles.
Volvo patented the first seat belt in 1885, which is the three-point design we see today. They even gave the patent information to other automakers for free, saving countless lives since. However, it wasn’t until the mid-20th century that the federal government required seat belts.
Although Maryland previously mandated seatbelt use for only front-seat occupants, a 2013 law expanded this requirement to all passengers.
How Seat Belts Work
Seat belts function by distributing the force of a collision over the sturdier parts of the body, such as the chest, pelvis, and shoulders, reducing the likelihood of injury. Here’s a breakdown of how they work:
Three-Point Design: The three-point seat belt, used in most vehicles, combines a lap and shoulder belt in one continuous piece. The belt is anchored at three points: two on either side of the hip and one across the shoulder, creating a secure restraint that keeps the upper and lower body in place.
Retractors: Most seat belts include a retractor mechanism, allowing the belt to lock in a collision while remaining flexible during normal use. This mechanism uses an inertia reel, which allows the belt to extend and retract smoothly but locks immediately in response to a sudden jerk, such as a crash.
Energy-Absorbing Webbing: Seat belts are made from a durable, moderately elastic material that can absorb energy. In the event of a collision, the belt stretches slightly, reducing the impact force and softening the blow to the passenger’s body.
Pretensioners and Load Limiters: Vehicles built after 2008 include pretensioners in the front seats that pull the seat belt tight in the event of a crash, securing the passenger instantly. Load limiters then release a bit of the belt to prevent injury from excessive pressure on the chest.
Inflatable Seat Belts: Some vehicles have inflatable seat belts in the rear seats, which act as a cross between a seat belt and an airbag when a crash occurs. The bag will remain inflated for several seconds, better protecting occupants during a rollover.
Seat Belts Save Lives
The impact of seat belts on road safety is undeniable. The NHTSA estimates that seat belts reduce the risk of death for drivers and front-seat passengers by about 45% and the risk of serious injury by 50%.
According to the National Safety Council, “from 1975 to 2017, seat belts are estimated to have saved 374,276 lives.” The NHTSA says that buckling up reduces the risk of fatal injury for front-seat passengers of private passenger vehicles by 45% and the risk of moderate to critical injury by 50%. For light trucks, the benefits are even greater for front-seat passengers: a 60% reduction in fatal injuries and a 65% reduction in moderate to critical injuries.
Zero Deaths Maryland says that, “If everyone buckled up, about 45-50 lives could be saved each year in Maryland.” According to their Crash Data Dashboard, 117 unrestrained occupants were killed in crashes in Maryland in 2023.
Seat belts may seem like just a few strips of material, but they are essential for saving lives in unexpected situations. Always ensure that you and your passengers are buckled up every time you drive.
For more information, go to:
- National Highway Traffic Safety Administration
- Zero Deaths Maryland
- Governors Highway Safety Association
- Insurance Institute for Highway Safety
- Maryland Department of Transportation Motor Vehicle Administration
- Johns Hopkins Bloomberg School of Public Health
- National Safety Council
- AAA – A Seat Belt History Timeline
- org – How do Seat Belts and Car Seats Work?
- Volvo – The Three Points That Saved One Million Lives
- Car and Driver Magazine – The Three-Point Seatbelt Turns 60
- Consumer Reports – Anatomy of the Modern Seat Belt
- Bell Engineering – The Evolution of Seat Belt Webbing
- How Stuff Works – How Seat Belts Work
