How long should trouble signals and their restoration to normal be indicated at proper locations?

The correct duration for indicating trouble signals and their restoration to normal is 200 seconds. This time frame is established to ensure that personnel and responders have ample opportunity to notice, respond to, and address any potential issues indicated by the trouble signals. At 200 seconds, the signaling provides sufficient visibility and attention to the state of the system, facilitating timely corrective actions or acknowledgments of the system’s status.

Utilizing a standard duration like this contributes to maintaining a high level of safety and ensures that the signals are not missed or ignored due to insufficient time for observation. This is particularly important in emergency scenarios where clear communication is critical for effective incident management.

The other durations mentioned do not align with the established protocols, which emphasize a comprehensive response time to trouble signals. It’s crucial for fire department operations to follow standardized timeframes to prevent oversights that could lead to safety risks.