How to Understand How Automotive Air Bags Work

Air bags aren’t generally considered to be within the realm of the typical do-it-yourselfer (and rightly so) but of course, if you’ve got the right tools and manuals, anything is possible. A typical air bag system consists of several sensors located at various places within a car’s structure along with the air bag itself. All cars today have two front air bags but their application has now proliferated with many high-line makers offering or including side air bags (mounted in the sides of the seat or door panels), side air bag “curtains” mounted on the side of the interior roof panel and there are even rear seat bags available as well.

Difficulty: Easy

Instructions

1. A typical system has sensors located at the front fenders and other locations which measure shock, deceleration and so forth. When activated, they send a signal to the air bag which then initiates a fairly violent explosion to inflate the air bag. Early air bags detonated within 1/25th of a second or 250 mph. In order for air bags to detonate, several or all sensors have to be activated.

2. In case the battery cables break during an accident, air bag systems have backup power sources which supply the necessary power to detonate the air bags. So if you’re thinking of removing the relevant fuse from the system to deactivate the air bags in your car—don’t. To deactivate the air bags a deactivation procedure, listed in shop manuals, has to be followed.

3. And according to NHTSA (National Highway Traffic Safety Administration), if you want to deactivate the air bags in your car (because, for example, you sit too closely to the steering column) or install an on/off switch, you have to file a request form. Some cars, particularly pick-up trucks, now come with on/off switches for the passenger side.

4. Since air bags have been in use, there have been 3.5 million deployments with about 5,000 people being saved. There have also been about 150 or so deaths because of air bag deployment. That’s because the government mandated that air bags have to deploy with enough force to restrain an unbelted 160 lb. adult.

5. Air bag systems are evolving. Because of the flap regarding excessive air bag deployment force, current air bags are “depowered.” They deploy with about 5 percent less force, not really very much. The next step in air bag development is air bags that can sense collision force and therefore adjust the level of deployment force. Naturally, these will rely on high tech and expensive electronics. These safer bags a definitely more complicated but again, they will save lives.

6. So far, Americans have spent over $40 billion on air bags, and yes, saving 5,000 lives is important. Yet with over 40,000 people dying each year and with over one third of these (that’s 15,000) because of drunk driving/drivers, aren’t we putting the focus in the wrong area? Making cars safer is of course important but making cars more complicated and adding more and more safety systems will not make much of dent in the death rate unless something is done in other areas. I believe that there would be a far more dramatic decrease in the death rate if young drivers were taught how to drive correctly from the very beginning and doing something that’s truly effective about drunk drivers.