Close-up of OPP Twitter photo of ambulance accident scene.

It is unusual that an ambulance would be involved in a significant head-on collision on a typical arterial roadway in Brampton, Ontario, resulting in the death of an occupant of the striking car. Yet this occurred last evening on Queen Street West and McMurchy Avenue. One would expect the various lighting on the ambulance, which was reportedly on call, would be sufficient in night-time conditions to provide warning of its presence. It was reported that the ambulance was stopped, waiting to make a left  turn when the impact occurred. An obvious task of investigating police would involve looking at the pavement and documenting the location of gouges and tire marks that would place the positions of the vehicle at the time that the crash occurred. As the ambulance was reportedly pushed rearward tire marks leading from the impact to rest should have been created. This would quickly confirm what was initially reported by police, that the ambulance was waiting, and not turning into the oncoming vehicle’s lane. While event data recorder (“Black Box”) data should quickly establish the speed of the vehicles for several seconds before impact, it will not explain how the driver of the on-coming vehicle managed to direct his or her vehicle into the left turn lane and strike a fully illuminated, stopped, ambulance at such high speed.

We normally have an appreciation of the severity of an impact by simply looking at the amount of damage existing on both vehicles. It is important to look at the crush on both vehicles because, when there is a large difference in the stiffness of them, there can be considerable damage to the soft structure of one and very little to the stiff structure of the other. The idea is to consider how much kinetic energy was dissipated in the whole impact not just in one vehicle and this is often an interpretation problem when investigators make conclusions about impacts with transport trucks or trees. In the case of the ambulance it would have a relatively stiff front end yet we see substantial crush so, even though we cannot see the crush of the car, we would suspect even more crush at its front end.

The obvious mass difference plays a large role in reducing the potential of injury to the paramedics. There is also a slight benefit by being higher off the ground than a typical passenger car. The off-set of the direct damage is quite typical of what would expected as most head-on collisions involve such “left-to-left” contact on the front ends.

In the end there is some mystery here as to why this collision occurred in the manner that it occurred.