The Northport school board has hired an environmental firm to investigate odors parents say are making their children sick at Northport Middle School.

Parents voiced their concerns at a school board meeting Thursday night, saying that they keep pulling their children out of school due to the fumes inside the building.

Some say they want the middle school shut down until they find the cause of the odor. During the meeting, the board voted unanimously to hire the firm to find the source of the odor.

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The company will test the soil, air quality and interview children about their symptoms. The decision to hire the firm stems from recommendations from a committee comprised of parents, teachers and administrators.

The school district told News 12 in October it believed a new HVAC system was the source of the odor. It says air quality testing was done and no problems were found, but it would continue to assess the situation.

The environmental firm is expected to be at the school as early as today. News 12 reached out to the school district for comment.