The blaze in Lisbon Falls caused an estimated $500,000 to $1M damage.

LISBON – An investigation by the State Fire Marshal’s Office has found nothing suspicious in the circumstances surrounding a fire at the Knight-Celotex plant Saturday afternoon, according to Lisbon Fire Chief P. Sean Galipeau.

The investigation has now been turned over to the company and its insurer, said Galipeau

The fire, which caused damage estimated by fire officials at between $500,000 to $1 million damage was attributed to a “machine malfunction,” Galipeau said.

The fire burned through a 75 foot by 150 foot section of a roof of one building at the sprawling plant. Third-shift workers were told to report for work as scheduled, Galipeau said.

The fire, he said, started “in the middle of the drying process” as wood fiber material was coming out of the kiln before going to a trimmer. Galipeau described it as a “good stop” by firefighters, saying, “It could have been much worse.”

Record-breaking temperatures, in the high 80s, made it harder for firefighters.

Two unidentified firefighters, one from Lisbon and one from Durham, suffered from heat exhaustion and were transported by ambulance, one to Central Maine Medical Center and the other to St. Mary’s Regional Medical Center where they were treated and released.

Two trucks each – from Topsham and Bowdoin – responded for assistance, along with firetrucks from Brunswick, Bath, Durham, Freeport, Lewiston and Sabattus, were called to assist the Lisbon and Lisbon Falls firefighters. Firefighters cleared the scene of the 1:40 p.m. fire around 10:30 that night.

Last December, the Masonite Corp. sold the facility to Knight-Celotex, which is based in Chicago. Voters at Monday’s annual town meeting will decide whether to designate the 23.84-acre parcel as a Pine Tree Zone.