Heading to a national park this summer? You’re going to want to pack face masks as new versions of COVID-19 continue to spread across Utah and the rest of the country.

The National Park Service is requiring face masks on all forms of public transportation that are enclosed as well as in visitors centers and other buildings, regardless of vaccination status, in parks located in counties that have high community levels of COVID-19, according to the Centers for Disease Control and Prevention.

With the highly transmissible omicron subvariant known as BA.5 now dominant in the United States, more than one-fifth of the nation’s counties are at the high community level of COVID-19 where the CDC recommends universal masking.

In Utah, six counties — Salt Lake, Tooele, Summit, Piute, Grand and San Juan — are currently at the high level based on COVID-19 case counts along with hospital admissions and capacity. The CDC’s community levels are updated weekly after the Utah Department of Health and Human Services releases new data on Thursdays.

That means visitors planning to use park service facilities will need to mask up at Utah sites including Arches and Canyonlands national parks, Glen Canyon National Recreation Area and the Hovenweep and the Natural Bridges national monuments.

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Masking is optional at sites in counties with low or medium community levels of COVID-19, although the park service said visitors should follow signs and instructions from park staff and volunteers and check for updates online, at each park’s website.

The park service “continues to monitor and respond to the COVID-19 pandemic, working closely with the doctors and public health professionals in the NPS Office of Public Health to use the latest science to guide our decision making,” according to a public health update post.

While visiting a national park allows people “to relieve stress, get some fresh air and vitamin D, stay active, and safely connect with members of their household,” anyone with virus symptoms such as a fever or breathing difficulties, or who has come in close contact with someone with COVID-19, is urged to skip the trip.

The park service has relied on the CDC’s community levels of COVID-19 to determine when masking is needed since March, after new metrics doubling the number of cases required to mandate masks were introduced. Under the CDC’s previous measurement, more than 89% of the country is at the highest level of risk for the virus.