Abort switch operation shall provide what kind of indication?

• A. Audible and distinct visual indication of system impairment
• B. Visual indication only
• C. No indication required
• D. Audible only

Answer: (A)

When the abort switch is used, the system must clearly tell everyone that the release has been interrupted and is not discharging. This needs to be both heard and seen, so people in the area can respond promptly. An audible alert ensures attention even in noisy or distant locations, while a distinct visual indicator remains visible if visibility or hearing is compromised. Relying on just a visual cue or just an audible cue can miss someone—visual-only can be missed in smoke or bright light, and audible-only can be missed by those who are hard of hearing or in a quiet situation. No indication would leave occupants unaware that the system is aborted, which is unsafe. Hence, the correct requirement is an audible and distinct visual indication of system impairment.