It was a specific weight and size sphere on a tether which was released and swung down-into the door. The intrusion into the car's interior was measured.

The sphere's size and weight was not increased for larger-heavier cars (which should have been part of the calculation since moving that car via a car impacting the door would take more energy to move a heavier car) and really had little to do with a real side-impact, nor for the relative height of the center of the door, etc.

Simillar front-impact legislation was in place, using the entire front-end of the car where Mercedes was testing using the left-front offset collision as the model, which is the majority of frontal collisions (70% or greater IIRC).

I'll side with Mercedes-Benz's calculations and methods any time over the USDOT and NHTSA tests, spent most of my life around this stuff and the TUV/EEC standards. Not surprising that the Europeans pioneered much of the safety equipment on passenger cars (LSG, 3-point belts, crumple-zones, positively-displacing drivelines et al).

No disrespect to Ralph Nader and his followers, met him back in the '60s (long story) and he had good intentions and worked hard with the tools available, but it seems that many who have come since have had misguided safety directives and are more politically motivated than safety conscious.

Off my soapbox.

__________________

Gone to the dark side

- Jeff