Just the other day, I read about the line of duty death of a young firefighter who was tragically killed accidentally while doing “routine tire maintenance” on a piece of apparatus. Insomuch as I recall writing an article in one of my columns about fire apparatus and emergency vehicle tires some years ago, covering this subject again seems like a good way to honor our young brother.
How Much Do We Know About Our Apparatus’ Tires?
First and foremost, do you know how old your apparatus’ tires are? Did you know that all tires have a manufacture and an expiration date? Every tire has a manufacture date stamped on the tire, and every tire has an expiration date that vehicle manufacturers recommend is six years after the manufacture date. Some tire manufacturers recommend replacement at 10 years OR “follow the vehicle manufacturer’s guidelines.” The manufacture date on the tire is the last four numbers of the D.O.T. number, indicating the manufacture week and year. For example, if the number is 1617, it was made in the 16th week of 2017.
Most tires also have a speed and weight rating stamped on them. The weight rating is indicated by the number of plys used in the construction of the tire. The speed rating is indicated by the letter that follows the size and diameter number. This letter (usually H-Z) indicates the softness or hardness of the rubber compound used in the tire. An “H” rated tire will have a harder compound, and therefore a lower speed rating of 60-75 mph. A “Y” or a “Z” rated tire will have a much softer compound and will also have a much higher speed rating.
Our Rig Tires Look Great; Why Does Any of This Matter?
This was always one of the biggest bones of contention between my former fire chief and myself. He’d say “Carl, those tires look perfect. We don’t even put 200 miles a year on them, and we can’t afford to be buying new tires every 5 or 6 years.”
In the same way that a number of other PPEs (like Ice suits and drysuits) and equipment deteriorate over time, tires are no exception. Rubber is a natural compound that actually breaks down faster from lack of use than it does from having regular daily use. “Dry rot” is a real thing, and we don’t always see it happening right away. Biased ply tires also develop “flat spots” from sitting too long in one place. Flat spots do soften up once out on the road, but over time and seasons, they also help to break down a rig’s tires.
With regard to the importance of a tire’s speed rating, this applies to those ambulance, Quick Response rigs, and light-duty rescue trucks whose drivers fancy themselves Indy Car drivers. This is a simple concept; if the tires on the rig you’re doing 95 mph in on the way to a call, are only rated for 75 mph, you are a wreck that is simply waiting to happen.
As I travel to and from rural fire departments across the country, I regularly see great-looking apparatus tires that are better than 20 years old. I also regularly see grossly overloaded wildland/initial fire attack rigs (Type 5-7 ) that are rolling nightmares, simply based on the fact that their tires and suspensions just aren’t rated for what they are tasked with. I don’t offer this information to be judgmental in any way. I understand better than most about budget constraints, and dangerous is dangerous.
Routine Tire Maintenance: Risk vs. Benefit
Without knowing what “routine tire maintenance” means to you and your department, or who in your department might be tasked with doing routine tire maintenance, I ask you to keep what I offered above in mind. Using a tire gauge to check tire pressures and adding a bit of air from time to time seems like a no brainer, and usually it really is just that. However, if your apparatus tires are grossly past their expiration date that changes the otherwise “simple” dynamic of routine tire maintenance altogether. Overloaded trucks also change the dynamic of routine tire maintenance for obvious reasons.
When truck tires catastrophically fail, they are known to explode violently. The LODD that I refer to in this article was the result of an apparatus tire explosion. I do not know any of the details surrounding what caused the young firefighter to lose his life last week, nor do I suggest or imply that there was anything wrong with the tire involved in that particular explosion. Our jobs are fraught with dangers that are seen and unseen. Hopefully, as we learn and hone our craft as firefighters, we shine more light on some of those unseen dangers.
