What does a green light indicate on the MSA G1 SCBA?

A green light on the MSA G1 SCBA indicates that the unit is in operational condition. This signal provides reassurance to the user that the breathing apparatus is functioning correctly and is safe to use. It signifies that all systems are go, allowing the wearer to proceed confidently into environments where respiratory hazards may be present. Monitoring this indicator is crucial for maintaining safety while using the SCBA, ensuring that it is ready for immediate deployment without any concerns regarding performance or reliability.

The other options may relate to different states of the equipment, such as indicating a malfunction, maintenance needs, or air cylinder replacement, but they do not represent the successful operational status that the green light confirms. Thus, the presence of a green light is a critical element for ensuring safe usage in hazardous conditions.