Mold has prompted officials at Daytona State College’s campus in DeLand, Fla., to temporarily close down the school’s business hall.

The Daytona Beach News-Journal reports that air quality reports showed elevated levels of mold in 16 of 33 rooms tested, including black mold in one spot.

The air quality inspections were conducted in September and October by CFL Environmental Solutions. Generally, levels over 1,000 spores per cubic meter of air are considered elevated, said Chuck Brogdon, a mold assessor at CFL Environmental Solutions.

Two offices inside exceeded levels higher than 10,000 — with one reaching more than 27,000.

The most prevalent type of mold found at the college was aspergillus and/or penicillium.

In healthy people, it would take mold levels from 30,000 to 50,000 to start affecting large groups, Brogdon said. However, for those who are allergic, or who have respiratory problems or compromised immune systems, counts as low as 3,000 could cause reactions.

English professor Paulette Marek, who has worked in the building since 2012, says the conditions in the business hall have caused her to become ill. She says that she has developed an upper respiratory infection that will not respond to antibiotics, and lost 20 pounds.