Air Bag Basics Connecticut Department of Transportation Air Bag Basics Air bags are designed to keep your head, neck, and chest from slamming into the dash, steering wheel, or windshield in a front end crash. They are not designed to inflate in rear end or rollover crashes or in most side crashes. Generally, air bags are designed to deploy in crashes that are equivalent to a vehicle crashing into a solid wall at 8 to 14 miles per hour.
Air bags inflate when a sensor detects a front end crash.
The sensor sends an electric signal to start a chemical reaction that inflates the air bag with harmless nitrogen gas. All this happens faster than the blink of an eye. They cannot smother you, and they don't restrict your movement. Air bags are proven, effective safety devices. The number of people saved increases each year as air bags become more common on America's roads.