About 35 years ago, my brother was running a union job in west Texas sandblasting & painting oil tanks. He put 2 guys to work on a tank located in a small "tank farm". He went back to check on them 3 hours later and not much was accomplished. When he asked his guys why so slow, they told him that they would start their compressor and some yahoo running a job nearby would wait for them to get blasting atop the tank..then he would turn their compressor off.
My brother told them " start your compressor, then go back up and start working"..which they did. My brother waited behind the compressor, and when the yahoo shut the compressor off, he got a 12" crescent alongside his melon.. They weren't bothered after that !
Of course, that was 35 years ago when men could be men, without so much lawyer interference.