From EMSN reader Henry Brainard, Paramedic:
"Is it just me or do you see more of these huge fire department ambulances landing on their sides went hit by a auto? The latest in St Louis was hit by a Saturn. I don't remember the vans overturning this easy."
please send reply to emsn-news@att.net subject: ambo crashes
REPLIES
__________________
A Problem with Center of gravity maybe? Yup seen lots more these days...
Carl Martin
_____________
Its not just you
Carlyle MIller EMT-D
Support Services Coordinator
North Shore-LIJ Health System
_____________
All types of ambulances roll over given the right conditions. First ambulance crash NHTSA studied was an International (SUV) ambulance that rolled over during a high speed entry into a curve. NHTSA determined then, and it is still true now, that the vehicles center of gravity was too high and too far back. This high center of gravity issue carries over into vans, boxes and medium truck type ambulances. Ambulances struck from the side tend to fall over in response to the high center of gravity weight distribution. Ambulances trying a high speed turn or entering a curve at too high a speed tend to fall over.
Paul H. Coffey, EMT-I
Basic EMT Training Coordinator
MDPH/OEMS
Boston, MA 02116
_____________
Take alook at Dr. Nadine Levick's web site................www.objectivesafety.net
John Payne
_____________
The more dramatic accidents always seem to have a photo of an overturned vehicle- better attention in press coverage.
There are many factors that can affect a vehicle in a crash including the size and weight of each vehicle involved, the center of gravity of each vehicle, size and width of tire footprint, etc.
Notice that many states prohibit the use of extended "econoline-style" vans for use as school buses and similar uses (i.e. day care.) They can easily be overloaded and have a tendency to roll over due to a loss of control or heavy impact in a traffic crash. Yet these same vans are routinely used for Type II ambulances! Note that there will be a new mandatory stabilization system installed on upcoming Econoline Vans in an attempt to reduce the handling problems associated with this kind of chassis.
As for crashes with larger vehicles, any vehicle can be tipped over if enough force is applied correctly- I have even seen an Abrams tank that flipped over. Look how easily some race cars can "flip". The energy being used to propel a vehicle down the roadway must be dissipated in some manner when it is struck by another vehicle (or strikes another object.)
Most EVOC classes have a presentation that better explains this effect .
Someone who drives their personal vehicle for several days and then only occasionally drives an emergency vehicle may not appreciate the different handling characteristics and dynamics involved, especially if there is a big difference in the sizes and overall weights of those two vehicles. They can become easily distracted while responding to an emergency call and not realize they are in trouble before it is too late.
A better example may be driving your spouse's car for a night out instead of your primary transportation. It takes a while to get acclimated to all of the potential differences (i.e. braking, accelerating, turning, gauge placement on the dash, mirrors, seating) without bumping a curb sometimes.
We have a client that experienced a rash of accidents with their ambulance fleet and it took them a while to determine what they felt was a contributing factor. They were buying larger Type I units on International chassis where the crews were used to operating the smaller F-350 style of ambulance. When the larger unit was out of service for any reason, the crews transitioned back into a smaller unit. They then moved back into the bigger unit when it was ready. Accidents typically occurred whenever a transition into a different style of ambulance happened. They determined that the simple solution was to simply provide a vehicle of the same size and style as a spare whenever the primary vehicle was "down." Accidents went down! Fire Departments can experience the same problem when a "spare" pumper or ladder truck does not have the same braking, wheelbase, turning radius, etc. as the crew's primary assigned rig. You have to "learn" everything about that particular vehicle and it is usually accomplished when responding to an emergency call- not the best time to practice!
It stands to reason that the same thing can occur when moving crews around into different types of vehicles (Type I, Type II, Type III) since all of those vehicles have very different driving and handling characteristics. Same thing with different kinds of airplanes, large and small. Pilots have to become "rated" for each kind of aircraft they can operate and demonstrate that they understand the special handling characteristics of each one.
Organizations that operate a "mixed" fleet would do well to minimize the variety from both a safety and maintenance aspects. Volunteer organizations can be at most risk where the occasional "driver" may hop into whatever rig is available or assigned as "first out" that particular day.
Dale
_____________
I agree!
It's the ole' I'm bigger than you are theory! My Dad always said, "yes you are bigger then me. That just means you will fall harder."
Lloyd
_____________
Good, important information on the physical aspects.
However, it would behoove all of us who work in the rear of these vehicles to take a close look at the "Training" or lack there of.
When it comes to who should drive, who could drive and training we have failed ourselves.
Alex
_____________