Acting Mayor Kim Janey announced Friday a city-wide mandate requiring people to wear face masks in indoor public spaces, regardless of vaccination status, beginning August 27.

The mandate will not apply to children aged 2 and under. Gatherings “in private residences when no compensation is paid, private buildings that are inaccessible to the public, places of worship, private workspaces inaccessible to the public, or performers who maintain six feet of distance from their audience,” and people who are actively eating or drinking, are also exempt.

The decree comes as the city prepares to welcome back thousands of college students and as the highly infectious COVID-19 delta variant pushes the city's critical metrics upward.

Janey, who is running for a full term as mayor, said the mandate would boost public confidence and keep the city open and recovering from last year's shutdown.

"This new public health order makes wearing a mask simple, clear and consistent across the city," she said at City Hall Friday. "If you are inside a building that is open to the public, wear your mask."

As of August 14, the Boston's positivity rate stood at 3.4 percent, below the 5 percent threshold of concern, but above 2 percent the rate when Janey ended coronavirus restrictions in the city in May.

Hospitalizations, another crucial monitoring metric have also been on the rise. As of August 16, adult hospitalizations climbed to a weekly average of 82. The month prior, the same metric was at 30.

Political opponents have criticized Janey's pace of enacting protective measures against the delta variant surge.

Boston's mandate makes it the latest of a handful of cities and towns to readopt an indoor mask policy as COVID cases begin to spike, this time with the highly infectious delta variant. The announcement came the same day a reinstated mandate went into effect in Somerville went into effect, and other cities and towns including Belmont, Lexington and Salem have reinstated mask mandates.

Janey said the city is exploring enforcement options, including the possibility of fines, which would come through Boston's Licensing Board and its economic development office.

Asked for comment to residents frustrated with the city's oscillating COVID restrictions status, Janey responded:
"Unfortunately, COVID is still here with us and may be with us for quite some time…Therefore, we must do our part to keep ourselves safe, to protect our residents and we know that masks can help do that."

The city's latest vaccination data shows more than 60 percent of Boston residents are fully vaccinated, with 68 percent having received at least one dose, but those numbers vary widely by neighborhood and by race. Seventy-five percent of Asian residents and 60 percent of white residents are fully vaccinated. Latino, Black and American Indian residents are all below 50% vaccinated.