BOSTON — Final preparations are underway for a statewide face covering requirement which is set to take effect in Massachusetts this week.

Starting Wednesday, a mask or face covering will be mandatory — both inside and out — when social distancing is not possible.

Exceptions include children under the age of 2 and those unable to wear a mask or face covering due to a medical condition.

On the Esplanade Sunday, many people were enjoying the nice weather were wearing masks — but others were not.

A nurse working at Massachusetts General Hospital who has been treating COVID-19 patients made a plea for people to take those rules to heart.

Not complying with Gov. Charlie Baker's order could result in a $300 fine.

Several airlines have also announced that passengers will be required to wear face masks.

Starting Monday, JetBlue , Delta, United and Cape Air will require all of its passengers to wear face masks.

Flight staff have already been required to wear masks while flying.

JetBlue was the first major U.S. airline to enact such a rule.

Small children will not be required to wear masks.