It was just before 8:30 AM Tuesday when the Hermon Fire Department received a call from the Hermon Elementary School for "an explosion in the classroom."

Fire Captain Mike Simmons said, "They called us and one of the teachers said she heard an explosion in the room. She thinks it's the heater. We'd like you to come down and take a look."

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When Hermon Fire arrived on the scene and entered the school, Captain Simmons said there was a light haze in the hallway section of the classrooms.

As this was also the time that teachers were getting their classrooms ready to receive students as they arrived, Simmons said firefighters advised members of the staff to evacuate the building calmly and to keep kids safe and warm on the buses or in their vehicles until the source of the problem could be found.

"We did some investigating and used the thermal imaging camera, which is used to find hot-spots. The haze definitely had an electrical smell to it. So we started looking in the walls, to see if we could find the problem. We didn't find any evidence of that, so turned the lights off and checked the ballasts with the thermal imaging camera, and found the issue"

Captain Simmons says having equipment like the thermal imaging camera saves precious time in situations like these.

"If you see a spot that is hotter than it should normally be, that's usually your focal point."

Firefighters were able to narrow it down and identify the problem ballast and contact the maintenance person from the school to replace the ballast.

Captain Simmons said that while it seems like a blown ballast wouldn't be that big of a deal, but left unchecked...

"In the middle of the night, when nobody's left at the school, and the lights are still on, that could possibly start a fire in the ceiling area."

The thing that really prevented a tragedy from happening, Simmons said, is that school was open and someone noticed and called in to report it right away.

The Hermon Fire Department posted a video of what the thermal imaging camera picked up that day to the school on their Facebook Page.

Captain Simmons says to the naked eye, Firefighters wouldn't have been able to detect the problem nearly as quickly.

But thanks to the camera, the crew was able to pinpoint the problem spot, and fix it with less destruction (they didn't have to rip apart the lights to find the culprit).

Another job well done. Crisis averted.

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