NEW YORK (CBSNewYork) — A vaccine mandate took effect Tuesday at indoor restaurants, gyms and entertainment venues in New York City.

It’s the most aggressive step the city has taken yet to slow the spread of COVID and the Delta variant.

READ MORE: Mayor De Blasio Announces Vaccine Mandate For All New York City Municipal Workers, Including First Responders

The rule applies to both customers and employees, who can show proof using a paper vaccine card or various apps, like NYC COVID Safe.

“I’ll just carry a card,” said one patron at the Olympic Flame Diner on the West Side. “Just for the safety of everyone, I think it’s a good thing.”

The head chef at House of Brews on Restaurant Row said the establishment started checking proof of vaccination on Monday night.

“Everything is moving along fine, no problems at all. I think last night the manager said only two people didn’t have an ID on them. That was pretty good for the first night,” Paul Loftus told CBS2’s Natalie Duddridge.

COVID VACCINE

Day one of the indoor vaccine mandate at Lily’s Craft and Kitchen was smooth, but manager Jason Powell told CBS2’s Jessica Layton he wonders what will happen on a night his place is slammed or if it’s too cold to eat outside.

“When I got a big gang of of 16 people coming in, am I gonna go behind the bar and check everyone’s vaccination card when I’m 10 deep? That’s what we’re gonna have to think about,” Powell said.

Nearby at a Ninth Avenue Beer and Cheese shop, workers said every customer was prepared to prove they are protected.

“They kind of show us before we even have to ask,” employee Mark Grillo said.

The city is also offering free, online de-escalation training for staff preparing them for the possibility of an argumentative customer.

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So far, patrons that CBS2 spoke with were agreeable.

“Totally for it. I think for everyone’s safety, at this point with the Delta variant,” Hell’s Kitchen resident Sarah Lipton said.

“Delta variant is super real. Kids are getting sick, people our age are getting sick, and vaccines help prevent death,” said Alexa Freeman, also of Hell’s Kitchen.

Meanwhile, the owner of CrossFit Spot on West End Avenue, said he’s been asking for people’s vaccination status for months now.

“We’re going to keep doing what we’ve been doing,” Billy Delarosa said. “So we require everyone when they come in to show us a vaccine card. We add it to their profile. So we know as soon as they come in they’ve been vaccinated.”

At most gyms, customers only need to show their vaccination status once, and the staff will keep a record of it.

“We don’t want to go through the same thing as last year — lockdown and suffering,” a guest added.

The gym has a plan for anyone who is unvaccinated.

“We haven’t had an issue so far,” said Delarosa. “We’re going to try to meet them where they’re at. Even if that means catering to them, saying hey, giving them a workout they can do outside.”

Enforcement begins on Sept. 13. If businesses don’t comply, they could face a $1,000 fine.

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CBS2’s Jessica Layton contributed to this report. Editor’s note: This story first appeared on August 17.

Natalie Duddridge