CHICAGO (CBS) — Saturday was the third day for the Lollapalooza festival in Grant Park, and this time, a recommendation to bring a mask came alongside the music.

As CBS 2’s Steven Graves reported, festival organizers are requiring people to wear masks in indoor spaces. Those include the tents, some of which are enclosed.

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But masks are not required to get in or for outdoor areas. At the entryway, not too many masks were seen on people’s faces, though some were seen on wrists. Festivalgoers said people who went inside enclosed shops were ordered to wear a mask, and masks were provided.

This rule is in addition to the requirement of either a negative COVID test within 72 hours or proof of vaccination.

It is in response to worries about the easily-transmissible Delta variant, as the city also recommended masks in indoor public spaces in line with the Centers for Disease Control and Prevention.

Festivalgoer Emma Green said she will wear a mask as necessary, and had one on when she talked to Graves.

“With the new Delta variant, you just don’t know like what people might be carrying around, and I’m going to go see my grandma in a couple weeks. I don’t want her to get anything,” Green said.

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Meanwhile, outside of masking up at the festival, scenes on Chicago Transit Authority trains are also causing concerns. Photos show packed CTA trains with maskless people coming from the event.

Packed CTA Train After Lollapalooza

(Credit: Mike McDowell)

Doctors say it is a recipe for a superspreader.

“That’s happened in many places where the transit caused the infection, because the people are affected, even closer for a longer period of time,” said Dr. Robert Murphy of Northwestern University.

There is also concern about indoor afterparties or dinners for the two remaining days of the festival.

Meanwhile, businesses such as Himalayan Restaurant, which are profiting off Chicago crowds, hope Chicago heads in the right direction.

“Everything getting back, and we’re so happy to see Chicago back again,” said restaurant manager Pradep Tsapaliya — who is not presently requiring masks.

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Lollapalooza started on Thursday and runs through Sunday.