Which AFC color indicates an Alarm condition?

• A. Red
• B. Green
• C. Blue
• D. Black

Answer: (A)

Red is used to signal an Alarm condition because it commands immediate attention and is highly visible, which helps responders act quickly during emergencies. In most AFC and safety signaling systems, red denotes an active alarm state that requires prompt action. Green usually means normal or safe operation, so it wouldn’t indicate an alarm. Blue is often reserved for information or supervisory indications, not an urgent alarm. Black is typically associated with off or inactive states, not an alarm. So red best communicates an urgent alarm condition.