On a grassy patch of land on the corner of Marquette Street and Truesdell Avenue in La Porte, Indiana sat three very large and very shiny fire trucks. The third shift of the La Porte Fire Department was there in full uniform with a bunch of fire equipment and gear strategically placed on the lot. There was no fire. What was going on?
This was a training session for the La Porte Firefighters.
“Today we’re practicing Class B, which is flammable liquids,” LCFD Training Officer Erik Jedrysek explained. “We bought new foam, and we’re using up the old foam.”
The foam that Jedrysek spoke of is called Alcohol-Resistant Aqueous Film-Forming Foam or AR-AFFF. This type of foam is used on Class B fires because it is resistant to alcohol actions. The foam smothers fire and cuts off the oxygen supply. There are five classes in which a fire can be categorized: Class A- paper, wood and other plain materials, Class B- flammable liquids, Class C- electrical equipment, Class D- combustible metals and Class K- cooking oils and fats.
Typically AR-AFF is good for about 20 years. Unfortunately, the containers that hold said foam do not last that long. If the containers are opened, then the foam will have a much shorter shelf life. Also, foam can lose its potency if agitated too much, sort of like shaking a bottle of pop. This training session was a resourceful way to dispose of the old product.
The training session started with all the firefighters dressed in full uniform including their SCBAs (self-contained breathing apparatuses). Then they set up a controlled environment where they poured E85 (a blend of 85% denatured ethanol fuel and gasoline) on a special table. The E85 was ignited and then the firefighters proceeded to put it out with the foam. Once smothered, a firefighter turned a leaf blower on the foam or moved it around with a push broom. The reason for this was to demonstrate that though the fire is smothered, it could easily ignite again if the smallest bit of oxygen is introduced. When the flames flared back up, the firefighters turned on the hose and doused them with water to finish the job. This procedure was then repeated with pure gasoline.
“This was to show the difference between distinguishes. We’re practicing for real life situations,” said Jedryek.
The training session was successful and the firefighters made the job look easy, though the work they do is quite challenging. The time and effort that they must train to stay on the top of their game is admirable. In conclusion, this writer was quite happy to pay witness to the day’s events- though I stayed a safe distance away!