The North Penn School District will require masks for elementary students when school starts, and for secondary students as long as COVID-19 transmission remains substantial, under a plan approved by the school board Thursday night.

The unanimous vote by the board governing the county’s largest district followed nearly two hours of comment from divided community members — and comes as schools across the region are finalizing plans for fall. A growing number around Philadelphia have moved to require masks amid concerns over the spreading delta variant, though not all have done so, and the issue remains deeply controversial in many communities.

In North Penn, masks will be required for all elementary students and staff. But in grades 7-12, they won’t be required if the district’s level of COVID-19 transmission — currently “substantial” under federal Centers for Disease Control and Prevention thresholds — falls to “moderate” or “low.” A shift will only be made if transmission rates remain at that lower level for two weeks in a row, district officials said.

Teachers who are fully vaccinated and at least six feet away from students “will have discretion” to drop their masks during lessons, said Superintendent Curt Dietrich.

The CDC has recommended that everyone in schools be masked this fall, a position also backed by the American Academy of Pediatrics.

While neighboring New Jersey and Delaware have required masking in schools, Pennsylvania has left the decision to districts. It’s unclear how many are requiring masks: A Pennsylvania Department of Education spokesperson said it is not tracking local mask policies.

» READ MORE: New Jersey to mandate masks for students and staff. Pennsylvania will leave the decision to districts.

The Philadelphia School District is requiring students and staff to wear masks, and a growing number of suburban districts have moved in recent weeks to do so as well. The Montgomery County health department has recommended universal masking in schools, as did Bucks County this week — a reversal in position by that health department, which cited concern from area hospitals about their capacity to treat pediatric COVID-19 cases.

Some area districts have taken a different approach. In Montgomery County, the Spring-Ford School District earlier this week approved a mask-optional plan. And the Souderton Area School District is continuing to endorse a plan without required masking that will be considered by the school board next week.

Before its vote, the North Penn board heard vehement opposition to the prospect of a mask mandate, including from some who alleged political motivations.

“When I look onto this stage, I see people who fall into three categories: ignorant, greedy, and evil,” one man told the school board, declaring that “masks and CRT” — critical race theory, another focal point at many board meetings this summer — were “poison.”

» READ MORE: School board meetings turn tense with debates over critical race theory and masking

Another man invoked the Nuremberg Code, accused the school board of “actively participating in crimes against humanity,” and quoted from the Declaration of Independence: “Whenever any form of government becomes destructive of these ends, it is the right of the people to alter or to abolish it.” Others described masks as a matter of parental choice.

Those in support of masking pushed back, noting the public health benefits of universal masking, and calling for protecting children who are too young to be vaccinated.

“It is not one person or one expert or one study or one organization saying this — it is the overwhelming scientific consensus,” one woman told the board. “We either want to end this pandemic or we don’t. We can’t have it both ways.”