HOUSTON, Texas (KTRK) -- A report published by the U.S. Government Accountability Office shows around 41% of school districts across the country need to replace heating, ventilation, and air conditioning (HVAC) systems in more than half of their schools.
Some health experts worry inadequate systems could help facilitate the spread of COVID-19 when students and staff physically return to schools.
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"Unless the air system is bringing in a lot of fresh, outdoor, clean air, that's going to just recirculate the germs that are in the air already and that creates a problem for the students that are there," said Kelli Drenner, clinical assistant professor and program director at the University of Houston.
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"If [there is] COVID-19 in the air, it will just continue to re-circulate and that creates conditions for spreading," she said. "So, unless those systems can filter that out, then it has the potential to be a spreading event, and that creates problems for kids and staff and teachers."
According to the CDC's guidance on re-opening schools, schools should increase air filtration and increase the amount of outdoor air that flows through their HVAC systems.
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"If you have that capability in your system to make sure that fresh air is coming in, then you're not just recirculating the air that's already in the room," Drenner explained.
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