The order went into effect in L.A. April 10, which requires both shoppers and workers at essential businesses that are open during the coronavirus pandemic to wear a face covering.

This includes businesses providing food, like the Jersey Mike's at Terminal 2, but based on this video shot April 16 during the lunch hour ... the workers weren't complying.

As you see, at least 2 employees were serving customers without wearing masks -- including the one cutting the meats -- and we're told the guy at the register was wearing a face mask ... but it was pulled down to only cover his beard and chin, leaving his mouth and nose exposed.

Two men ordering food in the vid, including an apparent pilot, were also not covering up.

As you may know ... many health experts now suggest wearing a mask outdoors to prevent the spread of COVID-19, though it's not required in the majority of states and cities in the U.S.

However, in L.A. it's considered a misdemeanor to not comply, though Mayor Eric Garcetti has said he hopes people will voluntarily follow the order.

This Jersey Mike's might need a little more encouragement.