Carbon dioxide levels in Urbana Elementary School's portable classrooms do not climb high enough to cause medical problems, according to a June report by the Maryland Occupational Safety and Health office.
State Department of Labor inspectors visited the school in April after fifth-grade teacher Jeff Esko filed a complaint alleging that he had health issues caused by working in a portable classroom.
State inspectors did not find carbon dioxide levels exceeding the limit of 5,000 parts per million in any of the school's 14 portables, the report said. No health and safety violations were recorded in the final report, obtained through a Freedom of Information Act request filed by The Frederick News-Post.
Esko declined to comment on the report until he speaks with a lawyer.
Two state officials and Laura Olsen, the district's environmental health and safety manager, used hand-held carbon dioxide readers to record gas levels in each portable unit. Readings were taken at various times on multiple days, while unoccupied and with teachers and students present.
The highest amount of carbon dioxide observed was 1,580 parts per million, less than half the amount deemed unsafe for human exposure.
Rooms seen with higher levels of carbon dioxide were ventilated using only one of the unit's two fans, the report said. Teachers can control their classroom's ventilation by using the fans and opening windows.
Esko told MOSH in March that "excessively high levels" of carbon dioxide are seen each day in at least half of the school's portables. Teachers and students have had symptoms of carbon dioxide poisoning, including migraines, disorientation and fatigue, he said in the complaint.
"To improve ventilation, we are allowed to open the windows, but this does not always allow enough fresh air to circulate and ventilate the units," Esko said in the complaint. "Doors must be kept closed for security reasons."
The school district provides staff with appropriate training to use the equipment and did not intentionally harm any employees, the report said. Any problems with the system were incidental.
"Our schools are highly regulated environments," school system spokesman Michael Doerrer said. "We work closely with a number of agencies and organizations as we focus on the health and safety of our school buildings."
Inspectors also interviewed 12 other school employees as part of the inspection. Teachers said carbon dioxide levels can reach as high as 3,700 parts per million in the winter, according to the report.
Teachers union representative Jennifer Nguherimo did not respond to a request for comment.
Doerrer said the district works to make sure ventilation and HVAC systems are operating properly at all times.
"We have staff in the schools that regularly inspect our equipment to make sure the vents to the outside can be open and closed," Doerrer said. "Our principals and maintenance personnel work with teachers to make sure they're comfortable with the equipment in their classrooms ... that is our top priority in Frederick County."
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