Smoke billowed over the trees Sunday afternoon as firefighters from around the state of Iowa learned a new technique of extinguishing fires with foam. The training school was held at the Fire Service Institute at the northeast corner of the campus.

The technique of mixing foam with water was introduced by 12 instructors to over 35 firefighters, most of whom are volunteer firefighters. After spending Saturday and Sunday morning in the classroom, the firefighters were given the chance to get familiar with the equipment on Saturday afternoon. On Sunday afternoon they had hands-on training of how to use it.

“The foam is mixed in with water to improve it’s efficiency,” said Glenn Pribbenow, field programs manager for the Fire Service Institute.

The percentages of the mixture vary anywhere from one-tenth of one percent foam to six percent foam and 94 percent water, he said.

Because different foams are used on different fires, there were four evolutions of fires: a dumpster fire, a flaming hay bale, a car fire and a grease pan fire. Fighters were divided into four groups and everyone had a chance to deal with each evolution.

On the “Class A” fires, combustible materials including most building fires and grass fires, foam acts as an agent to break the surface tension of water and penetrate the materials burning, Pribbenow said. This foam works well on smoldering fires because it soaks into the material, cools it down and extinguishes the fire.

On “Class B” fires, like gasoline or grease fires, the foam forms a barrier over the fuel, like a blanket, and prevents vapors from escaping.

“It’s the vapor from the fuel that burns. When we can cover the vapors, the fire is easier to control,” Pribbenow said.

When the foam is sprayed out from the hose with the water, bubbles that look like dish washing soap bubbles float through the air.

Sunday afternoon was spent lighting and relighting fires so the firefighters could get familiar with the equipment. Each fighter took a turn and discovered for themselves the ease of fighting with foam.

Ed Choate, an ISU alumnus, said, “Fighting fires is a lot easier with the foam. It takes less manpower and equipment.”

As the afternoon wore on, different sounds filled the air. Bells of the air tanks warning the fighters that they were soon to run out of air, the thunder of the fire itself and the firefighters yelling as they wrestled with the hose.

Foam is not widely used right now, but Pribbenow hopes this school will clear any misconceptions about the latest fire fighting substance.