Thousands of fire apparatus accidents occur every year due to neglect towards and errors in tire maintenance, yet checking your tires is a critical element of fire apparatus care that can easily save lives. At FDSOA’s Virtual Fire Apparatus Trade Show, TJ Tennent, the president of Tennet and Associates and The Tyre Guy, gave a crash course on all things tires and wheels in effort to arm those listening with processes and tools required to ensure safe and accurate tire upkeep.
Before diving into the technicalities, TJ mentioned that a must-have tool is the Tire and Rim Association (TRA)’s Year Book since it was written by engineers and outlines all the industry’s standardized information needed to maintain tire usability, such as how much air pressure ratings and rim load capacities. It is necessary to understand that TRA’s standards show a range of options; if you’re ever unsure of what to do next, reach out to TJ for no charge! To buy a copy, head to www.ustra.org.
The first step in ensuring tire safety, of course, is choosing the correct tire for your vehicle. To find out the vehicle’s characteristics needed to determine the correct tire, utilize the Door Placard (on the door of the vehicle) that lists the gross front and rear weight, cold tire pressure and tire rim size. When referring to a commercial truck, it is key to understand the load range (which correlates to maximum load carrying capacity at max pressure), the rim size and inflation pressure. Once you’ve read the Door Placard, refer to the TRA Year Book’s standards to find the tire that fits the vehicle’s qualities. TJ highly recommended to stay within the placard’s range because, “when you do something different it is only a matter of time before the tires fail.” Under no circumstances should you put on a smaller tire than the vehicle is meant for – even when more cost effective – because if there is an accident you can be held responsible. If you desire to put a larger tire on than is meant for the vehicle, you must add the extra steps of changing the calibers, the roaders and much more; it can be done, but still is not recommended.
Reading the size nomenclature of tires can be confusing, so TJ broke “P225/60R16” down as an example: “P” stands for “passenger vehicle” (if “LT” was in place of “P,” it would mean “light truck”; “ST” means “special trailer” and “T” stands for “temporary”); “225” is the “cross section”; “60” is the “aspect ratio,” or the section height divided by section width (of sidewall to sidewall when the tire is mounted on the wheel and inflated); “R” stands for “radial”; and “16” is the rim’s diameter in inches. If there is no “P” (or “LT”, etc.), the vehicle then follows Euro-metric Standards (ETRTO) which would look like: 225/60R16; if the nomenclature has a “C” at the end, it is a commercial vehicle. It’s important to note that there are two types of tires: passenger vehicles have bias ply tires which have two plies and look criss-cross while commercial tires are called radial ply which have four belts with plies going around and up. The biggest difference between the two is the weight it can carry, providing another reason why TRA’s Year Book comes in handy.
Tennent and Associates Associates is a global tire forensics firm that supports clients as investigators and expert witnesses for liability cases involving tire failures that result in personal injury. The Tyre Guy, also a global firm, trains and supports Law Enforcement, Emergency Vehicle Technicians, Insurance Claims Agents and Fleets on tire related material. They also work with several automotive manufacturers to assist them with tire related concerns and actions. If you would like training by The Tyre Guy, TJ offers one-on-one zoom meetings and his staff and he will even travel to your location to provide one, two or three day classes. Email thetyreguy@yahoo.com to book or to ask TJ any questions!
The Virtual Fire Apparatus Trade Show was held on May 18 and 19, 2021, and involved over twenty-five experts who spoke about topics from safety to COVID-19 to emissions. If you were unable to attend, head to FDSOA’s YouTube Channel to watch the sessions available.
