Can Window Fans Safely Ventilate Philadelphia Schools Amid Coronavirus?

The School District of Philadelphia is installing window fans as one measure to prevent spread of the coronavirus in buildings, before students in grades K-2 return for some in-person learning Feb. 22. The district and city leaders have vouched for the effectiveness of the fans at circulating air in a classroom while not bringing in too much wintry outdoor air. But some parents, educators and union leaders are questioning whether a window fan can be effective. | From: NBC10/Telemundo62 (Read more.)