My first time shutting down a factory at the end of second shift for the weekend. I shut down the compressors first, and that hard stopped a bunch of other equipment that relied on the air pressure. Lessons learned. I spent another hour restarting then properly shutting down everything. Never did that again.
They use this mixture at my work as well. Flushing out large sub freezing cooling systems. We don’t dump it out on the street though.