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MA Commissioner Updates (11/2/2020)

Department of Elementary & Secondary Education

Frequently Asked Questions, Week of November 2nd, 2020

1.     As the weather grows cold, what is the guidance for ventilation in classrooms?

Schools and districts should continue to ensure effective implementation of the five most important core mitigation strategies for reducing the risk of transmission of COVID-19 as specified by the Centers for Disease Control and Prevention (CDC): masking, physical distancing, hand hygiene, cleaning and disinfecting, and contact tracing. Additionally, the CDC recommends that schools and districts adopt secondary mitigation strategies, such as maintaining building ventilation systems, to the extent feasible.


While the guidance on ventilation released this fall is still applicable to schools, DESE is providing these additional considerations for schools without operable HVAC systems or Unit Ventilators (Univents), especially as it may not be feasible to keep windows fully open due to cold weather:

·       Open windows and doors to the extent the building’s design permits. On cold weather days, keep windows open at least a crack to provide some supply of fresh air.

·       Communicate with your school community that increasing outside air will affect schools’ indoor temperatures. Encourage families and caregivers to send their students to school with plenty of warm layers in winter, as classroom temperatures could fluctuate throughout the day.

·       Consider using portable HEPA air purifiers in occupied spaces.

2.     How should schools determine what HEPA air purifier will work for their classrooms?
DESE recommends using the “Portable Air Cleaner Calculator For Schools,” created by the Harvard Chan School of Public Health and the University of Colorado, to determine the supplemental air purifier(s) best suited to supplement the range of spaces within your school building(s). The air purifier must have a HEPA filter to be effective against COVID-19, should have a high clean air delivery rate, and does not need additional add-ons such as ionizers or ultraviolet lights. Portable air cleaners are typically most effective in smaller spaces, and care must be taken when choosing a device to ensure it is sized appropriately for the room in which it will be used. Plan accordingly for subsequent filter maintenance based upon use and manufacturers recommendations.[1] Avoid air cleaning technologies that emit ozone.[2]

[2] https://www.epa.gov/indoor-air-quality-iaq/ozone-generators-are-sold-air-cleaners#:~:text=When%20inhaled%2C%20ozone%20can%20damage,body%20to%20fight%20respiratory%20infections.