An inspection of the Penn Valley Elementary School's ventilation system found a manual damper within the ductwork above the ceiling was "too far closed, allowing only (approximately) 30% of the maximum amount of fresh air it should have into this specific room," according to a release posted on the district website.
The county health department also noted the possibility of a variant strain of COVID-19 being a factor, citing the rapid spread within the class and that two family members of impacted students tested positive.
"The damper can only be seen by physically going into the duct. The automated system that controls the HVAC equipment did not trigger any alerts indicating repairs were needed. As you can imagine, the HVAC systems across our buildings have thousands of parts. Even with the best monitoring and maintenance, at times, parts do break."
It is not entirely clear if the diminished airflow caused the outbreak, but could be a factor, the statement says.
The Penn Valley Elementary School students have been quarantining since last Friday while the remainder of students remain in classrooms.
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