Training >> Browse Articles >> Police Driving


Preventing Blow Outs During Pursuits

Preventing Blow Outs During Pursuits

Lieutenant John Leas

Every so often, we come across something that stimulates our interest. For me, I’m a car guy, and if it has a motor, wheels and goes fast enough to scare me, that’s a good thing. For the last 22 years, I’ve been teaching cops at our academy the best strategies to avoid traffic accidents when operating emergency vehicles under some very challenging conditions. As an Emergency Vehicle Operations Course (EVOC) instructor, we constantly reinforce the importance of tires and their ability to grip the road. It’s no joke when we talk about the importance of “where the rubber meets the road.” Rolling friction is our friend – sliding friction is not.

Many times during EVOC training and out in field operations, we pick up nails, screws and other assorted objects that slowly deflate our tires. A lot of times, we never even notice the breech until the tire is almost totally flat. By then, we are stranded on the side of the road and out of service. Not only are flat tires a huge inconvenience and a frustrating waste of your valuable time, but they can be costly to repair. A safety issue that looms in the background is that under-inflated tires will run substantially hotter, creating some interesting handling characteristics just prior to the tire shredding or blowing out. This is not something you or I want to experience while rolling Code 3. Not a great way to end your work day, or your life.


We’ve all seen products advertised that say they’ll fix flat tires, or supposedly prevent them. Over the years, I’ve ridden a multitude of off-road motorcycles, quads, touring bikes, police motorcycles, and driven four-wheel drive sport utility trucks, cars and most police sedans since the 70’s. I’ve used many of the commercially available products in a variety of applications and have not been impressed with their performance. Some of the stuff out there is just a gooey, slimy mess that doesn’t work well, if at all. So, I’ve avoided these products and always carried a spare tire, just in case.

Recently, I met a guy by the name of Marcelo Gaffoglio, Director of PermaSeal Tire Company based in Ontario, California. Marcelo had found me via the Police Driving website ( and wanted to meet with me to demonstrate a tire sealant product. My first reaction was, yeah, right, here we go again, some more gooey, slimy junk you put into your tire that does nothing but irritate your tire guy when you go get your tire fixed or replaced. But what the heck, it was a free demo (and we all like free stuff) so I invited Marcelo to come on over and bring his bag of tricks.

Cops are usually very skeptical about whether products really work as advertised. Heck, our job is to get to the truth however it plays out. I’ve been a cop for over 30 years and I’m tough on new technologies like this because, in the public safety field, it’s got to work right. Lives depend on it. Yeah, I’m kind of passionate about officer safety – I’ve seen too many good men and women pay the ultimate price…

I decided to do a bit of research on Marcelo and his company. As I Googled around the internet (as my wife waited patiently for her turn on the computer), I learned more about Mr. Gaffoglio. It turns out Marcelo comes from an auto racing background (that got my attention), his family runs a very successful metal fabrication business in Fountain Valley, California, and PermaSealTire had recently established itself in Ontario, California. I found their website ( to be quite informative and enjoyed the video segment featuring Jay Leno’s Garage and the PermaSealTire product. Now, if you didn’t know it already, Jay Leno is quite the car guy with a fantastic garage facility in Burbank, California. But hey, that’s a future story….

Marcelo showed up at my San Diego office with his company van and examples of the PermaSealTire Sealant product. Although I was eager to see the live demonstration, there were a number of questions I wanted to ask first. I had concerns from a number of different standpoints: as a law enforcement manager, as an EVOC instructor, as a husband and father – was this product as safe and effective as it was advertised? Was it environmentally safe? Well, it was time to find out.


Marcelo explained that PermaSeal is an ethylene glycol based water soluble tire sealant that is installed into a new or existing tire. Okay, fancy terminology for a mixture of tire crumbs, adhesives and assorted liquids mixed together and injected into your tires through the valve stem. Now, I’m thinking, this can’t be “green” or good for the environment, but it is. Marcelo’s product had survived a multitude of external, certified product testing. Okay, that’s fine, but what about some of the negative things I had seen and heard about with other tire sealant products? Like messy, corrosive to wheels and tires; causes wheel imbalance issues, freezes, clumps up or causes excessive heat? Surprisingly, I found PermaSealTire had perfected these earlier challenges and offers an environmentally safe product that maintains proper tire pressure, permanently. Wait a second, did he say permanently? Okay, so if I pick up a nail or screw in the tire, find it and remove it, I don’t have to go to my tire guy for a plug repair? Never, ever? Now that’s cool… Hey, don’t get me wrong, I have a great tire and wheel guy but I don’t really want to be stuck at his shop waiting for a tire repair or replacement if I don’t have to. Life is too short!


I asked Marcelo about mixing PermaSeal with nitrogen in tires, which many of you folks prefer over regular air. This combination is actually preferred by PermaSeal as the nitrogen eliminates internal condensation that can cause degradation to the wheel. In plain English, that means it doesn’t eat away at your wheel or tire like other products out there. I also found that PermaSealTire is the only company to offer a written guarantee that treated tires will remain fully protected against air loss for the legal life of the tire. Now I like guarantees like that. I asked Marcello if he had ever had to honor this guarantee and he said no, as there had been no failures of his product. Wow, could this stuff really work? Well, let’s see…


After our lengthy discussion and question and answer session, Marcelo led me out to the parking lot where his company van and test vehicle, a newer Ford E250, was parked. The tires had previously been treated with PermaSealTire. I checked out the standard truck tires, specifically the left rear, to determine tread wear and proper air pressure. Everything appeared in very good condition. Marcelo pulled out a 2" by 4" piece of wood with several large nails protruding through the surface. He laid the board down in front of the left rear wheel with the nails protruding upwards about 3" above the wood surface (this reminded me of the earlier versions of spike strip devices). We ran an air pressure check on the tire about to be punctured (establishing a baseline). Marcelo drove the van over the board, breeching the tire at least 5 times with the nails. He drove down the street, made a u-turn and returned where we re-examined the tire. We talked for a few minutes and then conducted another air pressure check on the tire. Amazingly, the tire pressure had remained the same – there was no air loss, not even one PSI. That did not seem possible given what I had just seen. Marcelo told me this very same tire had previously been punctured during demos about 45 times with the same result – no loss of air pressure. Okay, now I have to say I was pretty impressed by all that but I had some more questions.


One of my major concerns for both the public and private sector was, if a PermaSeal treated tire is breeched by a nail, screw or other foreign object, will the tire remain safe to operate? You could just imagine running over a nail, getting into a high speed pursuit and then having the tire shred and fragment as a result of the puncture. Again, not a pretty picture when pursuing bank robbers at 100 mph! Marcelo asked an independent testing facility, the Rubber And Plastics Research Association (RAPRA) in the United Kingdom, to put this to the test. They put two ¼" puncture wounds into the crown of a tire with PermaSealTire installed, and then ran the tire at over 100 mph for a distance of 25,000 miles. The test results showed the tire did not heat up, distort or fail in any fashion, and the tire air pressure remained consistent. As I mentioned earlier, proper air pressure is the best defense during performance and pursuit driving.


Since we drive so many different types of vehicles, both personally and professionally, I asked if PermaSealTire Sealant can be used on bicycles, all-terrain vehicles, motorcycles, cars, trucks, semi-tractor trailers and heavy duty construction equipment. Marcelo said it can be used on any vehicle with pneumatic tires. In fact, with construction equipment, the product can withstand punctures up to ½" wide. Guess I’ll be giving my brother Jim, the heavy equipment operator, a call about this stuff. His guys are always poking holes in their tires at construction sites.

Many of us in management think about the analysis of cost versus benefit. So what does this stuff cost? Well, it depends on a number of factors such as the size of the fleet and their respective tire sizes. Marcelo says, on average, standard patrol cars like the Ford Crown Vic Police Interceptor will cost about $60 per vehicle for the material. PermaSealTire will come to your garage to train and certify your service technicians to install the product during scheduled maintenance times. In some cases, fleet managers have chosen to remove the spare tire in favor of gaining more trunk space because most flat tires are now eliminated. This is a welcome relief to your SWAT folks and Accident Reconstruction Teams that need the extra room in the trunk.


I found with PermaSealTire that this product can prevent flats before they occur. In my agency, we average about 80 flat tires every year. Now, that may not seem like a lot of flat tires in a large fleet, but think about the operational impact to services and our people. Not only is the vehicle out of service, but so is the operator (police officer, paramedic, firefighter, lifeguard). In some cases, a service truck is dispatched to change the flat tire (a costly luxury in most cases) otherwise the operator must change the tire by the side of the road. The additional hazard for us operators is the potential for an injury during the tire change exercise or being struck by another vehicle (usually a drunk driver). And if industrial injuries (or worse) occur, we experience worker’s comp claims and loss of employee services due to injury leave. Putting the cost issues aside, the biggest hurt for all of us is loosing our brothers and sisters to injury leave. That means less cover units on radio calls and that’s just dangerous.

On the positive side, PermaSealTire does maintain the proper air pressure in your tires for a 25% extended tire life, better fuel mileage and a 5% cooler operating temperature. For the Fleet guys and gals out there, the cost savings is always nice. With today’s gas and tire prices, every little bit helps!


Well, you know I was quite skeptical going into this demonstration and didn’t expect to see such a successful ending. I was quite satisfied with the results. This product offers great peace of mind and a higher level of personal protection for all vehicle operators, whether personal or professional. I asked Marcelo why, as a former race car driver, he chose to go into this field. It was refreshing to hear that he had been successful in life and now wanted to provide a product that would enhance the level of personal safety for emergency vehicle operators and the general public. Although PermaSealTire has been in existence for several years and used throughout the world, it is a fairly new offering to North America. Marcelo’s immediate goal is to move this product into our public safety fleets throughout the United States, especially in police cars, fire trucks, ambulances, and search and rescue vehicles. Eventually, he expects to expand to the retail market as well. No pun intended, but I think he’s on the right track.

John Leas is a Lieutenant with the San Diego, California, Police Department. He began his law enforcement career in 1976 with the San Diego County Marshal’s Office and has been an Emergency Vehicle Operations Course (EVOC) Master Instructor since 1986. John currently instructs at the San Diego Regional Public Safety Training Institute in San Diego where he teaches police academy recruits and in-service training courses on emergency vehicle operations. Lt. Leas is a graduate of the Bondurant School of High Performance Driving and serves as a Police Driving Associate to the Western Region, a website dedicated to educating and improving the safe operation of emergency vehicles across the nation. John can be reached via email at .

Disclaimer: The views and opinions expressed within this article are solely the author’s professional review based upon personal and professional experience.

PoliceLink School Finder

Save time in your search for a degree program. Use PoliceLink's School Finder to locate schools online and in your area.

* In the event that we cannot find a program from one of our partner schools that matches your specific area of interest, we may show schools with similar or unrelated programs.