Customers and vendors wear masks at a farmers' market in Key West, Florida, on September 17.
CNN  — 

All residents of Key West must wear masks any time they leave their homes – even when they’re able to keep a safe distance from others.

The most populous city in the Florida Keys issued the tough new mask requirement Thursday. It’s among the most stringent mask measures in Florida, where coronavirus cases have surpassed over 905,000 statewide.

If Key West residents repeatedly fail to wear a face mask when they’re in public, even when social distancing is possible, they can be fined up to $500 after a verbal warning and civil citation, the ordinance rules.

The ordinance exempts children under age 6, private workers and gymgoers, among some other groups.

Key West Mayor Terri Johnson said during a weekly update on Facebook she’d asked city manager Greg Veliz to authorize overtime for Key West police so they can better enforce the ordinance in areas with heavy foot traffic.

“We’re trying to regain control of our more crowded outdoor areas,” Veliz said during Thursday’s commission meeting.

Monroe County, home to the Florida Keys, has recorded nearly 3,000 Covid-19 cases since the start of the pandemic. Almost half of those cases were recorded in Key West, according to the county.

The county took a strong stance on coronavirus in March, when it closed off access to the Keys to anyone who didn’t live or work on the islands. The Keys, which see over 5 million tourists in a typical year, reopened to visitors in June.

Overall, Florida’s coronavirus response has been fairly relaxed despite recording the third-highest number of Covid-19 cases in the US. Gov. Ron DeSantis has resisted mandating masks statewide and in September allowed restaurants and bars in the state to reopen at full, pre-pandemic capacity.

But several cities and counties where cases have surged have enforced their own mask mandates. Miami-Dade County, the former Covid-19 epicenter and most populous county in Florida, has required residents to wear masks in public since July.