An air supply indicator apparatus for indicating an amount of breathing air remaining in a cylinder, the apparatus including a housing member having a first side integrally formed with an attachment member, the attachment member configured to be detachably coupled to an emergency breathing safety system (EBSS) or universal emergency breathing safety system (UEBBS) and a second side form with an enclosure, an air status management status indicator having a plurality of indicator light sources disposed on the housing member, and a processor disposed within the enclosure, the processor coupled to the air status management status indicator and configured to emit light from the plurality of indicator light sources based on received signals corresponding to an amount of air remaining in a cylinder.