Banner image: Student volunteers on the CU Boulder campus. Credit: CU Boulder

More than 98% of people at CU Boulder wore a mask indoors on campus this semester, and 93% of them wore it correctly, according to a Centers for Disease Control-sponsored study tracking mask compliance at 53 U.S. universities.

When outdoor locations on campus and nearby off campus were included, however, compliance slid to 79.4%, the researchers found.

“Our study shows a fairly high rate of compliance, highlighting the commitment many of our students have made to protect our community,” said Tanya Alderete, an assistant professor in the Department of Integrative Physiology who is heading up the research for the CU Boulder site.

With just over a week left of the semester and COVID-19 cases in some places slowly creeping up, she said it’s critical that students remain vigilant.

“The pandemic is not over yet, even if we want it to be,” she said.

For the study, Alderete teamed up with research assistant Kevin Clark to recruit 13 undergraduates as trained observers.

Each took a shift once a week from mid-February to mid-April, inconspicuously parking themselves in high-traffic places like dining halls, recreation centers, the Norlin Quad and the outdoor pedestrian bridge leading to University Hill.

With every three people who passed, they jotted down whether he or she was wearing a mask, if they had it on correctly, and what kind it was.

“I think we have all felt a little hopeless at times about the pandemic, like there is nothing we can do to help,” said Alex Jackson, a sophomore integrative physiology major who volunteered to be an observer. “This felt like a good opportunity to get involved.”

Across 8 weeks and more than 2,800 observations, the team found that, depending on the location, anywhere from 45% to 99% of people observed wore masks correctly.

Not surprisingly, people were significantly less likely to wear a mask outdoors or off campus: 71.5% of people off campus wore one, and 58.4% wore it correctly.

In some off-campus areas, like the pedestrian bridge at the corner of 14th and College streets, compliance was as low as 45%.

“If you are not wearing a mask on some side street on the Hil,l that is one thing, but these are busy areas where we really should be seeing good mask adherence,” said Clark.

Some places on campus, including certain common spaces, hallways and entryways leading to residence halls, dining halls and classroom buildings, also had less than perfect mask compliance, the study found.

“We still have some indoor areas where a few people are not wearing a mask or wearing it incorrectly and that should not be happening,” said Alderete.

On the upside, mask compliance on the Hill improved significantly and steadily over the course of the semester.

And after the CDC suggested it, study observers noted an increase in people double-masking, suggesting the student population is paying attention to public health recommendations.

Even after Boulder County lifted its local outdoor mask mandate April 2, mask wearing indoors and out remained high.

“If anything, based on our data, we saw more people wearing face coverings in the final weeks, especially off campus, than we had previously in the study,” Alderete said.

On Tuesday, the CDC updated its guidelines to say that fully vaccinated people no longer need to wear masks outdoors unless they are in crowded spaces.

But with hospitalizations remaining concerningly high in some areas and vaccination rates plateauing,  Alderete said masks remain a critical tool in controlling the pandemic.

To play it safe, she advises students to keep a face covering on hand and follow the “two-out-of-three rule”: Be sure you can do two of these three things (be outdoors, socially distance, or wear a mask) at all times.

“In the U.S., thousands of people are still getting sick and dying from COVID-19. And while vaccination decreases the risk of infection and the severity of disease, these risks are not zero,” she said. “This means that responsible behavior is still important.”

Through her hours of observation, Jackson said she did see the occasional mask resting on the chin, or hovering below the nose, and a few rigged up creations.

“I saw someone with a t-shirt tied around their face once,” she said.

But in general, she’s been pleasantly surprised at how much her peers have complied with the mask mandates.  

“There has been some valid criticism about student behavior this year,” she said, “But in general I would hope that these findings would give us students a little better rap.”