> Generator kicked on, fan belt snapped, exhaust filled the entire basement, rolled into the service elevator, starts coming out the 3rd floor (top of the service elevator) and the building was then evacuated.

I feel like a ton of these stories come down to infrequent use. I remember one where they’d tested the generator but only for like a couple of minutes each month and so the fuel in the tank was really old by the time there was a real outage and the generator clogged expensively about an hour in, right as people were relaxing and thinking it’d be smooth sailing until the main power line was restored.