Captured by Brownwood firefighter Jody Horton’s helmet camera, a column of orange flames climbed the wall of a trailer, then rolled across the ceiling in a widening ocean of fire.

A cacophony of sounds — voices muffled by firefighters’ air masks, intermingled with the shrieks, whistles and klaxon-like clangs constantly emitted from their breathing apparatus could be heard.

The fire was no accident. It had been set — by the firefighters themselves.

In the interior of the Brownwood Fire Department’s new mobile fire trainer, a 45-foot-long trailer, firefighters were getting science lessons, of a sort, from instructors with an Oregon-based training group. It was the science of fire — how a fire develops, grows and behaves in a compartment.

Assistant Fire Chief Grady Shuey said firefighters learn the signs of impending conditions such as:

• Flashover, when all the flammable contents of a room reach ignition and burst into flame. “It’s fatal to firefighters,” Shuey said.

• Back draft, when a fire that has run out of oxygen gets a whiff of new oxygen and explodes. “Very high heat,” Shuey said.

• Smoke explosion, when heat and smoke have gathered in a space, awaiting an ignition source.

Instructors Chris Baird and Matt Leech, representatives of a company called CFBT-US of Gresham, Ore., visited Brownwood last week and trained firefighters in the use of their mobile fire trainer. CFBT is “compartment fire behavior training,” Baird said.

Their purpose is to teach firefighters “how to deal with a fire in a box,” Barid said, noting that “a house is a box - boxes within a box. The idea is to understand fire behavior, what makes it do what it does, how it develops, goes through stages, how to understand and recognize extreme fire behavior.”

In the video from Horton’s helmet camera, firefighters, hoses and nozzles were silhouetted against the mobile fire trainer’s dancing flames. Firefighters used a new hose technique the instructors had taught - quick, short bursts of water, rather than a solid stream - to extinguish the fire.

The Brownwood Fire Department took possession of the $152,000 trainer in February. Ninety percent of the cost was funded by a federal grant that required a 10-percent city match, Fire Chief Del Albright said earlier.

The city’s Fleet Services has a truck that can be used to transport the trainer, which is parked at the fire department’s drilling grounds off Duke Street. Albright said the fire department will invite area volunteer fire departments to use the trainer, which might mean taking the trailer to volunteer departments’ locations.

The trainer can be used for more than setting fires. Other scenarios include practicing ventilation and search-and-rescue techniques, Albright said.