Johnson Siding leads the way in firefighting tech

JOHNSON SIDING, S.D. – The newest piece of firefighting apparatus joined the Johnson Siding Volunteer Fire Department’s arsenal on Saturday morning – a Darley MaxWASP, or Wildland Attack and Structure Protection vehicle.

The new Darley MaxWASP is designed for off-road firefighting.

It is a fully equipped fire engine, built onto a Ford F-550 chassis with a specially designed off-road suspension. As its name implies, the fire engine has the capabilities to fight both wildland and structure fires.

Todd Tobin, training officer with the Johnson Siding Volunteer Fire Department said that in the rugged terrain of the Black Hills, this vehicle opens up areas to firefighters that they couldn’t easily access before.

“We have a lot of driveways that are narrow getting back into properties in what’s called the wildland-urban interface,” Tobin said. “So, with a smaller engine, we’re actually able to be far more effective in getting into those particular structure fires.”

The only difference in capability between the MaxWASP and a full-size fire engine is its water carrying capacity. But Tobin pointed out that this little giant is also equipped with a state-of-the-art foam firefighting system that stretches that water to the max.

“This new engine that the Johnson Siding Volunteer Fire Department has just purchased has an advanced CAFS system that allows us to with less water actually fight more fire because of the way the system is designed,” Tobin said.

Firefighters getting familiarized with the CAFS foam firefighting system.

CAFS, or Compressed Air Foam System, mixes a detergent chemical into the water which reduces surface tension. It allows for greater coverage, superior heat absorption, and with its surfactant properties, better penetration into the nooks and crannies where fire can hide.

Firefighting foam has been in the headlines recently near Ellsworth Air Force Base, where foam chemicals used in fighting aircraft fires have polluted groundwater. But the foam used on the MaxWASP uses a different chemical than aircraft firefighting foam and is not harmful.

“The Class A foam that we’re using in the wildland, on vehicles like the WASP and in all of our compressed air foam systems, this is a water-based detergent, it’s a soap,” said Troy Carothers, compressed air foam system product manager at W.S. Darley and Company, the vehicle’s manufacturer. “It’s not unlike the same types of chemicals you’d use to wash your dishes or wash your car or wash your clothes.”

The MaxWASP cost just over $200,000, a significant savings over a full-size fire engine. It was fully assembled in Wisconsin using parts from Wisconsin suppliers.