Slowing Down Door Closer

[DownsLife+Safety]

Hello!

I’m working on a musical production for my school. Unfortunately, we have a stage door that slams shut and makes a very loud bang. It’s a hassle trying to keep the backstage area quiet during show times and we would like to get this fixed.
Is there a way to slow the door closer down so that it doesn’t slam shut while allowing the door to be code compliant?

Thank you!