Photo courtesy of Loddprevention.com
Ben Lang died when the ambulance he was riding in crashed into a tree.
In recent years, there have been a number of fire service injuries and fatalities that were a direct result of tire-related crashes. Few people realize the importance of keeping a vehicle's tires in proper working condition. Tire pressure, tire tread depth and road conditions all play an important role in keeping your vehicle safely on the road.
The portion of the tire which is in direct contact with the road surface is known as the "contact patch." This contact patch allows your vehicle to accelerate, steer and stop. Any compromise of this contact patch will adversely affect the safety of your vehicle.
A contact patch is only about the size of your hand. When you consider that there are usually between four to 10 tires on a fire service vehicle, you can see that there is actually very little contact between your vehicle and the road surface. For this reason, we must ensure that as much of this contact patch touches the road surface as possible. This is accomplished by keeping a close eye on tire pressure and tire tread depth during your routine maintenance checks.
A bald tire actually provides more traction on a roadway then a treaded tire. This is because there is more rubber actually meeting the road surface, thereby creating a larger contact patch. However, bald tires provide poor traction on wet roadways. As emergency responders, we must often fight adverse weather conditions such as rain, snow and ice during routine and emergency responses. For this reason, tire manufacturers place tread on tires. Tire tread is designed to channel rain, slush and snow away from the tire face, allowing the tire to stay in contact with the road surface.
As your tire rotates around the axel, the tire tread is constantly "pushing" water out of the way and allowing the tire to come into contact with the road. As it rotates, a wedge of water will build up in front of the tire. If you are traveling too fast and the tire does not have enough time to push this wedge of water out of the way, the vehicle will rise up on top of the water and the tire will lose contact with the road surface. As a result, you will lose all steering and braking control. This situation is what's known as "hydroplaning."
Should you find yourself in a hydroplane situation, research has shown that you should take a firm grip of the steering wheel, take your foot off the accelerator and do not touch the brakes. You should attempt to keep your vehicle on a safe heading by not turning the steering wheel. Hopefully, the vehicle will regain traction and you will be able to safely control the situation.
There is little that you can do to remove yourself from a hydroplane situation once it happens. Instead, it is important to prevent this situation all together. The best way to prevent your vehicle from hydroplaning is to slow down in wet or inclement weather. The faster you go, the more likely you are to hydroplane. It is not uncommon to see vehicles hydroplane at speeds as low as 30-40 mph.
In addition to slowing down in bad weather, keeping a close eye on the condition of your tires will also help keep your vehicle safe. A tire that is under inflated tends to hydroplane at slower speeds. This is because there is less tire pressure inside of the tire to push water out of the way. You should consult your tire and vehicle manufacturer to determine the proper air pressure that you should keep in your tire. Once you know how much air to keep in the tire, make sure to check the tires with a tire pressure gauge at least once a week.
It is also important to keep a close eye on the depth of your tire tread. Federal guidelines require 4/32 of an inch on your steering tires and no less than 2/32 of an inch on your rear tires. However, studies have shown decreased performance in inclement weather when tire tread reaches 5/32 of an inch or less. Purchase a tire tread depth gauge at your local automotive store and keep a close eye on the condition of your tire tread. When the tread reaches 5/32 of an inch, notify your fleet maintenance personnel and begin the process of replacing your tires.
Hydroplaning is an extremely dangerous situation that can be easily prevented through proper training and maintenance on your vehicles. Ensure that your drivers realize the importance of slowing down in wet weather. By driving responsibly and performing regular maintenance checks on your tires, vehicle safety will improve.