The **seat belt** is a crucial element for **passive safety** in a vehicle. Its main function is to **protect the occupants** in the event of an accident or a sudden impact. When properly fastened, the seat belt prevents people from moving from their seats or being ejected from the vehicle, which significantly reduces the risk of serious injuries.

- **Impact protection:** The seat belt prevents the driver’s or passengers’ bodies from hitting the **steering wheel** or the **windshield** during an accident. This is essential to minimize physical damage.

- **Proper placement:** For the seat belt to be effective, it must be correctly adjusted. The **shoulder strap** should pass over the collarbone and the center of the chest, while the **lap belt** should be placed over the hip bones. Incorrect placement can reduce its effectiveness and increase the risk of injuries.

- **Inspection and maintenance:** It is important to periodically check the seat belt to ensure it is in good condition and meets quality standards. A defective belt will not provide the necessary protection.

In summary, the seat belt is essential to prevent the body from hitting parts of the vehicle such as the steering wheel and the windshield, thus protecting the occupants from serious injuries in the event of an accident.