NORTHFIELD – A two-alarm fire inside a local factory building caused the evacuation of 120 workers Friday morning.

The fire was reported just at about 11:30 a.m. in the front section of PCC Structurals at 24 Granite St., authorities said, when a caller reported smoke coming from the roof, according to Tilton-Northfield Fire Department Chief Bradley Ober.

Ten employees of the company were evaluated for smoke exposure problems on the scene by medical crews, but none were found to suffering ill effects, Ober said. No firefighter were injured.

A 2½-inch hand water line was used to initiate an interior attack of the flames, Ober said. A backup water line was established after more firefighters arrived, he said.

“Due to staffing levels and potential for large volume of fire, a second alarm was requested,” Ober said in a press release. “The fire was under control in approximately 45 minutes.”

The fire appears to have been caused by a wax buildup in one of the building's exhaust fans, said Joe Shoemaker, the company's human resources manager. The company makes castings for engines and a variety of uses, he said.

The fire occurred in the building's aluminum aerospace department, though Shoemaker and fire officials weren't sure what started the wax burning.

“Some pipes caught fire and smoke filled the building quickly,” Shoemaker said. “We got everybody out quickly.”

Firefighters made a good “save” at the building, he said, and the damage was kept to one section of the building, he said.

Ober said several systems in the factory were damaged by fire and will require replacement and/or repair, and the section of the factory where the fire occurred will be shut down for several days.

It was the third fire this year on Granite Street, though the fires were not related, Ober said.

The Tilton-Northfield Fire Department and EMS companies were assisted by firefighters from Franklin, Sanbornton, Belmont, Laconia and Gilford, while Northfield Police and Tilton Police assisted at the scene. Belmont and Concord Fire Department provided station coverage.