Car Safety Features

The primary purpose of anti-lock brakes is to prevent a car's wheels from locking during panic braking. By allowing the car to slow in a more controlled manner, the driver can often maintain better steering control and avoid an accident. There is a bit of physics behind ABS design that has to do with static friction, but the benefit can be summarized by stating the ABS allows a car to slow down faster than "skidding."

New cars sold with ABS typically have four-wheel anti-lock breaks. Sports Utility Vehicles (SUVs) and light truck are sold with either two-wheel (rear wheels) or four-wheel ABS.

Electronic Stability Control is designed to help drivers to maintain control of their cars during times of intense steering maneuvers. ESC helps drivers by preventing a car from spinning out of control. It does this by constantly monitoring wheel speed and applying braking force to one or more wheels as needed.

Tire Pressure Monitoring Systems use a warning light on the dashboard to alert the driver when a tire is significantly under-inflated. Tires in this condition are more prone to failure (a blow out). The standard for this warning is to signal the driver when the tire pressure is 25% below the manufacturer's recommended inflation pressure.

For example, if the tire is supposed to be inflated to 30 psi of pressure, the TPMS will alert the driver when the tire pressure drops below 22.5 psi. All cars manufactured after September 1, 2007 are required to have TPMS.

Daytime Running Lights turn on the car's headlights whenever the vehicle is being driven. By turning on the headlights, even in the daytime, the ability of other drivers to see the car is greatly enhanced.

Seat belts are considered the single most important safety device installed in a car. These belts are designed to keep passengers in their seats, which avoids impact to the steering wheel, dashboard, windshield, and even other passengers. When buying a car, sit in the vehicle and put on the seat belt. Check to make sure the fit is comfortable. Many cars today offer a variety of ways to adjust the seat belt to obtain a better fit.

All new cars are required to provide a warning light and audible signal that lasts for at least eight seconds if the driver or front seat passenger does not have a seat belt engaged.

The original air bags deployed in cars were placed in the steering wheel, and they were designed to protect the driver. The success of these devices in protecting passengers has led to their deployment in several new ways.

Frontal Air Bags

Frontal air bags for drivers and passengers have been standard equipment in all cars since the model year 1998. These bags are designed to prevent the driver, or front seat passenger, from striking the windshield, dashboard, or steering wheel. Frontal air bags are usually hidden in the steering wheel and in the dashboard itself.

Advanced Systems

After September 1, 2006, all new automobiles were required to be fitted with advanced air bag systems. This system is designed to deploy air bags in such a way as to balance the protection of the passenger with the force by which the bag is deployed. The advanced system can help protect some adults, and especially small children, from the harmful effects of a bag that deploys with too much force.

On / Off Switches

Nearly all vehicles that do not have a rear seat now include an on / off switch that can deactivate a frontal air bag. For example, an on / off switch might be commonly found in pickup trucks; allowing the passenger side air bag to be turned off when transporting a small child.

Side air bags are designed to offer additional passenger protection from side impact collisions. These types of bags take several forms:

• Curtains / Tubular: bags that deploy downward from the car's roof.

• Combination: deploy upward from the seat back, and provide both head and chest protection.

Out of Position Test

There has been a recent movement to test side air bags for safety when a passenger is out of position, such as a child or adult sleeping with their head resting on the inside of a car's door. If the vehicle has passed a series of tests for safety under these conditions, it will be noted in the car's safety literature.

Rollover air bags are designed to keep passengers inside a vehicle when a special sensor activates. These bags perform this safety function by staying inflated for a longer period of time.

Using forward-looking sensors, these pre-collision systems alert drivers when their automobile is getting too close to the vehicle immediately in front of them. If the driver does not respond to the collision avoidance warning, specially equipped vehicles are able to automatically apply the brake to avoid a collision.

Oftentimes displayed on the rearview mirror or an in-dash display, the driver is able to see objects behind them when backing up the vehicle. These video cameras can be combined with sensors to alert the driver if they are getting too close to an object as they are backing up.

The final safety feature we're going to mention has to do with the vehicle's weight. Once again, this has to do with physics (actually quite a bit of a car's behavior can be explained by physics) but the rule of thumb here is that heavier vehicles offer passengers a greater level of safety. This rule of thumb comes with some cautions.

Statistically, some of the heavier vehicles on the road today are trucks and SUVs. Because of the typical dimensions of SUVs, its center of gravity is higher off the ground compared to a passenger car. This makes SUVs more prone to rolling over. So while an SUV offers passengers the advantage of being a heavier vehicle, this advantage can be negated by their tendency to roll over.