What aural chime must the FAs hear when pressing the ATTND button during the preflight inspection on the ERJ 175?

When the flight attendants press the ATTND button during the preflight inspection on the ERJ 175, they must hear one HI/LO chime. This aural signal is an important confirmation that the system is functioning correctly and that the intercom is operational.

The HI/LO chime serves as an indicator that the communication system between the flight attendants and the cockpit, as well as among the cabin crew, is working properly. This is crucial for ensuring that safety protocols are in place and that the crew can effectively communicate with each other during the flight. The one HI/LO chime signifies readiness and allows the flight attendants to proceed with their preflight checks, reinforcing the importance of functional emergency communication systems on the aircraft.