Time and time again the common factor during apparatus accidents is excessive speed. We need to get off the accelerator and slow it down a bit. As "professional" drivers and responders, we need to learn to control adrenaline rushes and take a step back, take a deep breath, and remind ourselves to kick it back a notch and stay in control.
To hone our stay-in-control skills further, operate a driving simulator. I had the opportunity to experience and drive in one. The simulator could select time of day, weather, terrain, type of fire or EMS apparatus, road conditions and incident type. It could also introduce obstacles for evasive maneuvers (e.g., pedestrians, pedestrians on bicycles, cars entering the intersection, disabled vehicles in the middle of the roadway).
Repeatedly, simulations show speed is the primary collision culprit. Once we learned to slow down, there was a dramatic improvement in the number of collisions/accidents.
In all of this, remember that larger vehicles take longer to stop. It is a basic principle of kinetic energy. We are not driving normal passenger vehicles or performance sports cars. Most, if not all, of these larger vehicles use "air brakes." Even though they perform better than hydraulic brakes, there is an inherent aspect called lag distance.
When you step on the brake pedal of a hydraulic brake system, the reaction of the force applied to the pedal is almost instantaneous to slow down the vehicle. With air brake systems, there is at least a half-second delay between applying the brakes and the air pressure to go through the system to reach the brakes at the tires/wheels.
The formula goes like this: perception distance + reaction distance + brake lag distance + effective braking distance = total stopping distance.
With hydraulic brakes, you eliminate the brake lag distance. For instance, based on the Florida Driver's CDL handbook, the air brake lag distance at 55 mph on dry pavement adds about 32 feet. So at 55 mph for an average driver under good traction and brake conditions, the total stopping distance is more than 450 feet for a tractor trailer commercial vehicle (perception distance 142 feet, reaction distance 61, brake lag 32, braking distance 215 = 450 feet).
Most fire apparatus carry about the same if not more weight than a commercial tractor trailer.
Despite this, many believe an ABS system helps to stop a vehicle in less distance. According to the National Highway Transportation Safety Organization, "ABS is designed to help the driver maintain control of the vehicle during emergency braking situations, not make the car stop more quickly. ABS may shorten stopping distances on wet or slippery roads, and many systems will shorten stopping distances on dry roads. On very soft surfaces, such as loose gravel or unpacked snow, an ABS system may actually lengthen stopping distances."
Some departments have adopted a policy testing reaction time electronically from accelerator to brake pedal. Drivers must fall within the parameters (time) set forth by the policy or else they are not allowed to operate an emergency vehicle. It may be the wave of the future.
At the department I worked for, we did a simple experiment. We responded to different addresses with and without emergency lights and sirens. The total time that was saved was approximately one minute.
There is no doubt seconds do count in our line of work. But for minor injury responses (after being screened by dispatchers and set response protocols), we had a policy in place that we would not respond on a "3" with lights and sirens. It did not merit endangering crews and civilians.
The immediate way to resolve cutting down on the total braking distance and reaction time is simply to get your foot off the accelerator and hover your foot over the brake pedal when a situation presents itself. This can be applied for any driver of any type of vehicle.
Just constantly keep your brain working and saying to yourself when driving and scanning your environment, "what if." I always preached the three "S's" to the firefighters I instructed: slow down, stop, and seat belts. Remain safe!
This article was written for & published by MultiBriefs.