MIDDLESEX BOROUGH — Parents say that their children have been struggling with headaches and staying awake at the borough middle school. Turns out that poor ventilation has been causing a build up of carbon dioxide — a natural byproduct of breathing, but a gas that could cause people to suffocate in large amounts.

Schools Superintendent Linda Madison informed parents on Tuesday that Von Mauger Middle School is "safe" following tests on Sept. 14 by the NJ Public Employees Occupational Safety and Health (PEOSHA) Program at the state Department of Health.

The test showed that several classrooms contained carbon dioxide levels exceeding 1,000 parts per million but the PEOSHA representative said that this does not represent a health hazard. The report encouraged teachers to open windows and recommended that the school inspect its HVAC system in order to improve air circulation.

"Students and staff should continue to attend school as they normally would," Madison wrote.

But parents and the mayor are upset with how the school district is handling the situation.

About 100 parents kept their kids home on Tuesday to send a message to the school board.

Mayor Ronald J. DiMura, meanwhile, said school officials should have taken action sooner and notified municipal authorities.

“If it is true that the superintendent has known of this very dangerous issue for two years and has not disclosed the information to our office and notified the proper health officials, that is completely unacceptable,” DiMura said. “If the problem was discovered years ago, it should have been resolved and not still exist today. These conditions need to be thoroughly addressed immediately, regardless of what work is required.”

In her letter to parents, Madison said that Dr. Richard Lynch, an independent certified industrial hygienist at Environmental Safety Management Corporation and a former professor of industrial hygiene and public health at Rutgers University, is inspecting the building this week and conducting an air quality study of the building

Her letter did not address any instances of carbon dioxide prior to Sept.14.

Madison told CBS New York that the school's ventilators were supposed to have been replaced over the summer but time ran out. The work will be completed next summer, the report quoted her as saying.

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