Contaminated HVAC system prompts temporary closure of middle school in North Carolina

The Rowan-Salisbury (N.C.) school district has temporarily closed West Rowan Middle School after microbial growth was found in the school's HVAC system. 

The school building will be closed until Sept. 9 to thoroughly clean the facility, reports The Charlotte Observer. 

Until then, classes will be taught online.

Results from recent testing confirmed the presence of microbial growth in the HVAC system, district officials said, and the growth “cannot be addressed effectively at this stage if students and staff are in the building.”

Earlier this month, an independent consultant also tested the HVAC system after custodial staff reported some microbial growth in the school. Results of that testing “came back negative for mold, and additional janitorial crews were brought in to thoroughly clean and sanitize the impacted areas," the district said in a news release. 

But new evidence of microbial growth emerged Aug. 17, and tests began the same day. Officials are investigating why the growth returned despite the cleaning.