What if students won’t wear masks in class? Professors want assurances that universities will enforce a mandate.

For weeks, colleges have been slowly rolling out their plans to welcome back tens of thousands of students in the fall.

Now, concern is bubbling among faculty and staff about what happens when they get there.

Leaders at Pennsylvania State University on Friday received a petition signed by nearly 900 faculty — about 12% of the total — demanding the right to bar from their classrooms students who refuse to wear masks, and the autonomy to decide whether to teach in person or online. They have asked the university to outline clear procedures for handling violations of social distancing, mask wearing, and other safety protocols.

“Faculty feel that their concerns about personal and public health are being ignored or downplayed by administrators, and that they are being subjected to a dangerous, potentially deadly experiment without their informed consent," said education professor Esther Prins, one of the signers.

That came as a Temple professor had an op-ed published in the New York Times claiming that most college reopening plans were so “unrealistically optimistic” they border on “delusional” and could result in virus outbreaks among students, faculty, and staff.

And nationally, there’s no consensus on how to handle mask-wearing. Some states, including Oregon, are requiring it on campuses, while others, such as Virginia, will encourage it, The Chronicle of Higher Education reported. Pennsylvania has said students, faculty, and staff should wear masks “in all classrooms, public shared spaces on campus, or in areas where social distancing cannot be observed.”

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That leaves open the question of what happens when they don’t.

Steve Newman, president of Temple’s faculty union, said professors should have the right to ban a student who steadfastly refuses to wear a mask or to immediately shut down the class.

“That question of what rights an instructor has to insist and react if somebody is not complying with the rules is a pretty important one,” he said.

Discussions with faculty are underway at Pennsylvania’s 14 state universities, said Jamie Martin, president of the statewide faculty union.

“We’ve been in negotiations with the state system and the office of the chancellor in trying to voice some of those same concerns,” she said.

It has not been decided how noncompliance will be handled, said Dave Pidgeon, spokesperson for the Pennsylvania State System of Higher Education.

Temple and Penn State said they will require mask-wearing in university buildings, including classrooms; educate students on its importance; and consider refusal a conduct violation. At Temple, security guards will bar students from entering buildings if they don’t have masks on, said spokesperson Ray Betzner.

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But exactly what enforcement steps will be taken if students refuse to don a mask in class is unclear.

Penn State intends to provide guidance to instructors on how to enforce the rule, said spokesperson Lawrence Lokman.

“The guidance will provide details about how instructors can set clear standards of behavior, encourage shared responsibility, and hold students accountable,” he said.

But faculty are skeptical that approach will work. Risky behavior peaks among people in their late teens and early 20s, and there’s no reason to believe behavior around mitigating virus transmission will be any different, Laurence Steinberg, a Temple psychology professor, wrote in the Times op-ed.

But Martha Compton, president of the Association for Student Conduct Administration, a national group of campus administrators working in that area, said she believes most students will comply. At Penn State, more than three-quarters of nearly 6,000 students who responded to a university survey said they would wear a mask in class.

Compton said schools should handle mask wearing as a public health issue, similar to seat belt wearing and no-smoking campaigns, which sought to alter behavior on a large scale. Students should be educated on reasons for masks, given clear expectations and instructions, and be reminded when they forget, she said. Exceptions or accommodations should be made for students with health conditions that make mask-wearing difficult and for deaf students, she said.

For those who fail to comply after repeated warnings, “then you have to use the tools in the tool belt,” she said.

More risky behavior, such as a student who tests positive and breaks quarantine, should be dealt with differently, she said.

“For me, that’s absolutely a place where a university needs to step in and take some action,” she said.

Not all schools intend to require masks.

“We don’t want faculty or staff to have to police mask use," said Jayson Boyers, president of Rosemont College, a small, Catholic liberal arts school.

Rosemont instead will go with strong encouragement and an education campaign on why it’s important, said Boyers, who is new to Rosemont this month.

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“Even if after our education program a student refuses to wear a mask,” he said, "that student can be set further apart from all the others in the room. Our size … will allow for that.”

But Boyers acknowledged that large universities, with thousands of students coming from distant places, will have a harder time enforcing social distancing.

At Penn State, faculty who organized the petition had been discussing concerns even before the university released its plan Sunday to bring back more than 110,000 students and employees to its campuses around the commonwealth. The release of the plan, which calls for testing, contact tracing, and a hybrid of online and in-person classes, did nothing to allay their concerns, said Sarah Townsend, an associate professor of Spanish and Portuguese at the main campus.

“The plan itself is very vague,” she said.

She also asserted that there should have been more widespread faculty input. Fewer than 20 faculty served on the 300-member task forces, she said.

The university is planning town hall meetings for later in the week and will take more input, Lokman said.

Townsend said faculty also are seeking other assurances, including job security and free testing and coverage of health costs if employees get the virus. Chief among concerns, too, she said, is that faculty wants a guarantee they can decide for themselves whether to return for in-person classes.

Both Temple and Penn State have set up systems for faculty and staff to make that request, and they’ve pledged to work through issues with employees, but neither has promised to honor every request.

“We also have an obligation to our students, and we have to be mindful to that,” Betzner said.