In my aerospace days, our buildings had both ionization and temperature detectors, plus water flow on the sprinklers. Any detection would sound loud buzzers locally, but two sensors, or water flow, had to trigger before everything powered off. That's common in big installations.

We once got an alarm because the heating element in a computer room air conditioner had turned on for the first time ever. It was defective and started to smoke. Smoke detection tripped, buzzers sounded, lights on a panel showed where the problem was, and alarms went off in the security control center. But this didn't trigger building evacuation or full power down. That took confirmation from a second sensor.

Someone ran into that computer room, saw smoke coming from the A/C unit, and pulled the big red power switch, installed by the safety people, on the air conditioner. Then we had time to shut down normally, the safety people came to clear the alarm, and the HVAC people came to fix the problem. I kept the burnt heating element on my desk for a few days for people to see.

This is typical for big industrial plants. Bad stuff will happen, and you have procedures for it.