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on dry roads, it will take how much to react to a hazard and bring your car to a stop when traveling 55mph at

“Total Stopping Distance” Total Stopping Distance is the total distance that it takes you to see a hazard, process the hazard in your brain, apply the brakes, and come to a complete stop. To understand this concept we first have to understand speed in terms of “feet per second” instead of “miles per hour”. 55 MPH is equal to about 80 feet per second, so in one second your vehicle will traverse 80 feet. Stop and think about that. It takes the average person around 1.5 seconds to see, process and react to a hazard. So from the time you see the car pulling out in front of you to the time your brain processes the “Uh Oh” and causes your foot to push down on the brake pedal, you’ve traveled about 120 feet! Now you have to apply your brakes and come to a stop. Let’s be honest and figure that you aren’t the greatest at “Threshold Braking”, or working your brakes so well that they don’t lock up. Instead, we’ll assume that you lock the brakes up and start skidding to a stop. Skidding to a stop in a fire truck will take around 194 feet. Let’s add that to the reaction distance and we see that it takes around 314 feet to stop a fire truck while traveling 55 MPH on dry roads. Imagine that…it’s an entire football field. On a wet day, this distance can be as much as 500 feet! Still want to approach a “stale green” light at 55 MPH and just assume that no one will pull out in front of you? I certainly hope not. The thing to remember is that this Total Stopping Distance was calculated using PROVEN formulas used by crash reconstructionists. These formulas use variables for speed, distance, coefficient of friction and braking efficiency. Nowhere in the formula do we multiply for years of experience or how good you think you are. In other words, if you’ve been driving for 40 years and teach advanced EVOC, you’ll still need 314 feet to stop your truck…just like the brand new driver in the pumper behind you!

“Coefficient of Friction” – The coefficient of friction of a roadway essentially measures how “slippery” it is. A dry asphalt roadway usually has a friction value of around 0.8 to 0.9. This value is important, especially when crash reconstructionists are trying to determine how fast a vehicle was traveling from skid marks. On wet or icy roads, these values can drop to 0.2 or 0.3! What does all this mean? Drives must be aware of road conditions because they significantly affect how fast our vehicles can travel. The lower the friction value, the longer it takes a vehicle to come to a stop. Slippery or wet roads will reduce operating speeds by a large margin. You can’t drive the same way on a dry, sunny day as you would on a cold, rainy day. I’ll show you why in a minute.

“Seatbelts” I believe that this one is a no-brainer. We all go to crashes in the middle of the night and as we are cutting the deceased occupants out of the wreckage we say to each other, “If they’d just had their seatbelts on”. But what do we do after we put the tools away? We climb into the rig and drive back to the station without our seatbelts! But we’re firefighters and paramedics. We don’t need seatbelts, we are invincible. WRONG! Mother Nature could care less what your occupation is when your fire truck slams into a tree. Or worse yet; when the truck rolls over and you are flung out the open window to land 75 feet down the road. There really isn’t much explaining to do for this particular topic. It all comes down to personal responsibility. Drivers are responsible for ensuring that everyone is restrained, Officers are responsible for ensuring everyone is restrained, and the individual firefighters are responsible for ensuring that everyone is restrained. To not wear your seatbelt is just plain dumb. Put it on, people!!

Why do fire trucks crash? It’s simple, we drive too fast and we don’t wear our seatbelts. I also believe that fire apparatus operators aren’t trained properly to understand the physical forces of Mother Nature that influence how an emergency apparatus will behave on the road. Fire Departments send their drivers to an Emergency Vehicle Operator Course (EVOC) and think that these classes magically create Superdrivers. The problem is that many EVOC courses fail to address the dynamics and physics behind large vehicle behavior. Those classes that do address these issues are often taught by instructors who don’t necessarily understand them. Granted, there are some great instructors out there, but they just don’t know how to explain these concepts. The vast majority take this section of the class and gloss over it. The usual mentality is “Let’s just get through this chapter quick and go to lunch, no one will understand it anyway.” This creates a generation of apparatus operators who don’t know the limits of driving a large vehicle. I equate it to teaching an EMT class without going over basic anatomy. The student knows how to put on a bandage, but doesn’t know why he or she is doing so. This is why we must concentrate on training our drivers to understand how Mother Nature sets limits on how fast we can drive our apparatus.

Speed is commonly referred to in “miles per hour” (mph), butit is easier to understand speed if we think of it in terms of “feet per second” (FPS). To convert speed from mph to fps, we simply multiply mph by 1.466. For example, 55 mph x 1.466 = 80 fps. So if you are driving down the highway at 55 mph, you are also traveling at 80 fps.  Let’s apply this idea to perception and reaction time.

So from the time you perceive the hazard until the time your foot is applying pressure to the brake pedal, you've traveled 120 feet but your car still isn't stopped. At 55 mph, on a dry road with good brakes, your vehicle will skid approximately 170 feet more before stopping. This distance, combined with the perception and reaction distances, means you need about 300 feet to stop a car traveling at 55 mph. As a point of reference, Lambeau Field is 360 feet long, end to end. Keep this in mind as you follow that other car on your way home tonight.

A fire truck without ABS brakes that is traveling 55 mph on a dry, asphalt roadway takes approximately 393 feet to come to a complete stop. On a rainy day with a wet road, the total stopping distance can increase to as much as 510 feet! The next time you are looking for something to do for drill, go outside and measure off 510 feet. Still want to drive 55 mph on a wet road?

If you are traveling at 50 miles per hour, it will take 50 feet just for you to react and put your foot on the brake. Of course, the stopping distance varies depending on the surface of the road, the condition of the brakes, and the skill of the driver in recognizing and reacting to hazards.

REACTION TIME: Use your foot to “cover the brake” as you proceed through an intersection. By covering the brake pedal, you significantly reduce the reaction time necessary to respond to a hazard and also allow the vehicle to slow by removing your foot from the accelerator. The “covering the brake” technique can be used effectively in the following situations: (1) When driving next to parked cars, (2) when you see the brake lights of other cars, and (3) when approaching intersections or signal lights.

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If your vehicle stalls, you must move off the road as quickly and safely as possible. Turn on your hazard lights immediately. Shift the vehicle in neutral and try to focus on the nearest shoulder. Once out of the road and stopped up flares or reflectors around 200-300 feet behind your vehicle to warn others of the danger. Never switch off the ignition until you 're on the road and you stop, that this action will lock the steering wheel and brakes will have more difficulty functioning. When it is safe, all occupants must exit the vehicle and move safely away from the vehicle. However, if this happens on the highway, you should consider the situation before making decisions that affect your safety. If you are sure it is safe, flares on the road; If you are not sure, just stay inside with all your passengers and keep them on your seat belts. Call for help if you have your cell phone with you or wait for help to arrive. Be aware that in the fog, warning lights and flares / reflectors will attract other vehicles and should not be used.

Do you know how long it takes for your vehicle to stop? The speed you are traveling is a key factor. The higher the speed you travel, the longer it takes for you to stop. But speed is not the only factor affecting the stopping distance. When you encounter a danger, you have to react. Your reaction time is the distance your vehicle travels in the time it takes for you to identify threats, react by braking, and move your foot on the brake pedal. No matter how fast you think you can react, you still need time to respond to a situation, and then stop.

Trucks are powerful and heavy, often weighing four to five times more than a typical car. They are equipped with a maximum of eight mirrors, but still they are involved in numerous traffic accidents. Motor vehicle operators have no general respect for trucks, often tailgating or get stuck between a truck and the curb. A driver must also be aware of blind spots of the truck. Studies have shown that a truck trailer traveling at 55 mph will usually need twice the stopping distance for a car traveling at the same speed. This is why pilots should never cut in front of a truck, especially when the gap between the truck and the vehicle in front is small to begin. Particular attention should be given when driving trucks on the highway near. The trucks should receive an additional certificate whenever possible, with the driver of the car always leaving an escape option on the road. Drivers should be aware of blind spots of a truck at all times, realizing side mirror mirror of a truck are not always sufficient. A common blind spot for a truck driver exists near the right front wheel of the truck, and another is within 30 feet of the rear of the trailer. Therefore motorists should never tailgate of a truck, move to the right of a truck cut in front of a truck, or a parallel drive a truck for any length of time.

Road lights should be used with caution. Do not use the high beams when approaching within 500 feet of traffic. When behind another vehicle, turn off the lights when you are within 200 feet. You can not see as far into the night, and common sense says to slow down. You also need to plan ahead when driving at night and use a card if necessary. Become familiar with alternative routes if necessary. Give yourself extra time for night driving. Getting lost is never fun, especially at night. It can cause stress, delays or collisions. You should also know that it is illegal to drive with only your parking lights on except when they are used as indicators or in conjunction with the headlights.


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