Philadelphia drops its mask mandate.

Philadelphia residents no longer need to wear masks in most indoor settings, starting immediately, the city’s health commissioner, Dr. Cheryl Bettigole, announced on Wednesday.

With Philadelphia reporting an average of 295 new coronavirus cases per day, down from almost 4,000 during the Omicron peak, city authorities say it is safe to stop enforcing the mandate.

The change in policy came as other U.S. cities and counties have rapidly relaxed their mask mandates, including Chicago, Washington, D.C., Los Angeles County, New York City and Boston.

Last month, Philadelphia announced a new tiered Covid response system, which ties restrictions to specific benchmarks for new daily cases, hospitalizations, test positivity rates and the rate at which cases are rising. The metrics have improved enough that Philadelphia can move to the “all clear” level, where vaccines and masks are no longer required in most indoor spaces, the Health Department said.

The mask mandate remains in place in health care settings and on public transit, and businesses and other institutions are allowed to require masks or proof of vaccination if they choose to do so.

Masks will no longer be required in Philadelphia schools starting March 9, if the situation continues to improve.

“Philadelphia is unique in that we are the poorest big city in the country, making us more vulnerable to Covid-19 than many other places,” Dr. Bettigole said. She added that Philadelphians had shown a commitment to each other during the pandemic, “perhaps best demonstrated by our willingness to wear masks for the past six months to help decrease transmission to those that remain at risk.”

Almost 70 percent of Philadelphians are fully vaccinated, according to a New York Times database, but the number of people receiving their first doses has stalled, as they have nationally.

Other places in the United States that announced changes to mask policies this week:

• Maine’s state government said on Wednesday that it would lift its statewide mask requirement for schools on March 9, after which school districts will be responsible for setting mask policies.

• Education officials in Chicago, one of the largest U.S. public school systems, say they might soon end the city’s mandate in schools.

• Los Angeles County is poised to lift its indoor mask requirement for unvaccinated residents on March 4.