I really like this image. One thing I would add though, are signs and warnings. I occasionally work in the basement below a paper machine, an enviroment not too different to your pic. Everywhere are warnings about automatic valves, hot surfaces, slippery surfaces, moving equipment, and the need for special safty equipment. We also have colour coded ducting and electrical boxes to speed up ident in case of emergency or maintainance. Also, everything has an area Letter and a section Number Just a thought.