A thread about false fire alarms reminded me of this one...
Back in '85 I had a summer job at Lethbridge Community College, grounds keeping. Mowing lawns, laying a couple acres of sod around a new building...anyway, one day my boss Mike asks me to go into the fenced play area of the day-care to mow it, had been skipped for a couple weeks. Gate is too small to get Kubota lawn tractor in, so I grab the John Deere push mower and off I go. Of course the grass is a foot tall, and the JD is bogging and blowing blue smoke, but I'm getting it done. Almost finished, and I look up and there is Mike with about 4 fireman and they are all hollering at me (I had muffs and glasses on per safety)...shut it down and I'm all 'what?'....
The main air intake for the whole building's HVAC was right above this little play area, sucked up the blue smoke and set off alarms. Major call out as multiple zones triggered at once by the vent system circulating it...think it cost the college $2K back then, there were about 7 or 8 trucks there and hoses rolled out all over the place...
Whoops! Not my fault, Mike wanted to be mad at me but I was just doing what he told me to.