But Glen Ellen Fire Protection District Chief Peter Van Fleet this afternoon defended his cadet and described him as "a smart kid and a hard worker."
Reports that the boy entered the burning cabin on Trinity Road east of Santa Rosa and went on the roof to ventilate it prompted the DES investigation.
The DES oversees 15 all-volunteer fire agencies within 960-square miles of unincorporated Sonoma County in Service Area No. 40. The Glen Ellen Fire Department is not among them.
The fire at 1579 Trinity Road was in the DES's Mayacamas Fire Department jurisdiction but Glen Ellen firefighters were the first to arrive, DES Fire Chief and Director Mark Aston said.
Aston said the fire agencies his department oversees are prohibited from using trained teen volunteers under age 18 to actively fight fires but they may help mop up after fires and provide supplies during the fire response. The Glen Ellen Fire Protection District has its own policies, Aston said.
Glen Ellen firefighters did not inform the incident commander that a minor was among their responders, Aston said. The incident commander would have assigned the teen to "an appropriate role," Aston said.
The boy, who received Boy Scouts Explorer Program fire training at the Kenwood Fire Department, and an adult firefighter with the Glen Ellen Fire Protection District suffered "heat stress from physical exertion" during the fire and were treated at Sonoma Valley Hospital and released, Aston said.
Van Fleet said the boy and the adult firefighter, who were likely exhausted, did not want to go to the hospital but complied as a precaution.
The fire was reported shortly after 7:30 a.m. Thursday at the one-story mountain cabin that serves as a second home for the owners, who live in San Francisco, Aston said.
The blaze caused significant damage to about half the structure. No one was home when the fire started.
Van Fleet said the teen was initially at the doorway of the cabin helping get hoses into the structure. He then went to the roof with an adult firefighter to ventilate it but was called back down, Van Fleet said.
The boy entered the cabin with a firefighter to douse hot spots only after vent fans were installed and the fire was under control, Van Fleet said.
"The structure was safe and the fire was under control. Once under control, there is an element of training involved," Van Fleet said.
The teen was fully aware of the limitations on him as a cadet volunteer, Van Fleet said.
The teen's father was a Glen Ellen volunteer firefighter and his uncle is a current volunteer, Van Fleet said.
The boy will receive four months of additional training at a Glen Ellen fire academy before he is 18, Van Fleet said.
Kenwood Fire Department Chief Bob Uboldi said the teen received Boy Scouts Explorer Program fire training at the Kenwood post over two years and lives in Glen Ellen. The Glen Ellen Fire Protection District does not have an Explorer program, Uboldi said.
"He responds (to fires) with Glen Ellen," Uboldi said.
"Our Explorer Scouts can't participate in an active fire attack and can't go into a working fire," Uboldi said.
"The problem we had was he was identified as a fire Explorer Scout. He was not there as a fire Explorer. He was on the fire as a Glen Ellen cadet. They have their own rules," Uboldi said.
Van Fleet said Aston is satisfied with his explanation about the cadet's role in fighting the cabin fire.
Van Fleet said it would be "a darn shame" if the negative publicity about it dissuades other youths from entering the fire services.
"It's wonderful to have young people who are willing to get off the couch and do something for their community," Van Fleet said.