Mercedes Benz Crash Test Data - Deceleration of the Head

Our head is like a pendulum and so it is the most vulnerable part of our body in a crash. In cars without an airbag, the deceleration is quite violent and lasts a very short time. The Head Injury Criterion (HIC) is very high, indicating that the occupants' heads will be injured. (See the Description of HIC in a later section.)

The A-3 ms Value

The A-3 ms value in these graphs refers to the maximum deceleration that lasts for 3 ms. (Any shorter duration has little effect on the brain.)

If an airbag is present, it will expand and reduce the deceleration forces. Notice that the peak forces (in g) are much lower for the airbag case.

The blue rectangles in these deceleration graphs indicate the most critical part of the deceleration, when the maximum force is exerted for a long duration.

With an airbag, you are far more likely to survive the crash. The airbag deploys in 25 ms.