Ventilation during COVID-19 in a school for students with intellectual and developmental disabilities (IDD)

Abstract

Background: This study examined the correlation of classroom ventilation (air exchanges per hour (ACH)) and exposure to CO2 ≥1,000 ppm with the incidence of SARS-CoV-2 over a 20-month period in a specialized school for students with intellectual and developmental disabilities (IDD). These students were at a higher risk of respiratory infection from SARS-CoV-2 due to challenges in tolerating mitigation measures (e.g. masking). One in-school measure that is suspected to help mitigate the risk of SARS-CoV-2 infection in schools is classroom ventilation. Methods: We established a community engaged research partnership between the University of Rochester and the Mary Cariola Center school for students with IDD. Ambient CO2 levels were measured in 100 rooms in the school, and air changes per hour (ACH) were calculated. The number of SARS-CoV-2 cases for each room was collected over 20 months. Results: 97% of rooms had an estimated ACH ≤4.0, with 7% having CO2 levels ≥1,000 PPM for up to 3 hours per school day. A statistically significant correlation was found between the time that a room had CO2 levels ≥1,000 PPM and per-room SARS-CoV-2 PCR confirmed cases, accounting for 21% of the variance. No statistically significant correlation was found for room ACH and per-room SARS-CoV-2 cases. These findings led to ongoing efforts to upgrade the ventilation systems in this community engaged research project. Conclusions: There was a statistically significant correlation between the total time of room CO2 levels ≥1,000 PPM during the school day and SARS-CoV-2 cases in that room in an IDD school. This research partnership identified areas for improving in-school ventilation.