Rear crash protection: Hummer
For each seat/head restraint, rear-end crash protection is an assessment of occupant protection against neck injury in rear impacts at low to moderate speeds. Although such injuries usually aren't serious, they occur frequently.
The overall ratings are based on a two-step evaluation. In the first step the geometry (distance behind and below the head of a seated average-size man) is rated good, acceptable, marginal, or poor. Seats with good or acceptable geometry then are subjected to a dynamic test simulating the forces in a stationary vehicle that's rear-ended by another vehicle of the same weight going 20 mph. Seat/head restraints with marginal or poor geometry aren't tested dynamically because they cannot protect taller people in rear-end crashes. These seats are rated poor overall.
In the dynamic tests measurements are recorded on a dummy (BioRID) representing an average-size man. BioRID is designed specifically for rear-end testing at low to moderate speeds. The dynamic ratings are derived from two seat design parameters (acceleration of the dummy's torso and time from impact initiation to head restraint contact with the dummy's head) plus tension and shear forces recorded on the dummy's neck. Overall ratings are based on both geometric measurements and dynamic results.
More about the procedures for rating seat/head restraints
Good
Acceptable
Marginal
Poor
| Model | Seat type | Overall rating | Dynamic rating | Seat/head restraint geometry |
|---|---|---|---|---|
| H3 2006-2010 |
Manual-power leather seats |
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|
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Note: Seat/head restraints with marginal or poor geometry aren't tested dynamically because they cannot protect taller people in rear-end crashes. These seats are rated poor overall. Seat/head restraints with good or acceptable geometry are also tested dynamically.
Rear crash protection test details (technical information)
