When I was young and weighed 160 pounds, I got hired on to run condensate drains for air conditioning that was being added to a downtown Seattle hotel. The Mayflower Park Hotel on Olive and 4th Ave. Much of the system I was installing tied in between the lobby floor and the 2nd floor. The space between the wire mesh with mortar that was the lobby ceiling and the concrete structure was 14" with nails embedded in the concrete pointing down. If you rolled onto your side, it was easy to embed those nails into your hip. Movement was by slithering on your stomach. There was a little bit more space between the beam structure, but not much.
Access was a 16" x 16" square cutout in the ceiling that was reached by a ladder. I spent six weeks in that slither space making the plumbing happen. There were times my heart was beating so fast, that I had to close my eyes and picture myself somewhere else until things slowed down. When I was finished and ready for an inspection, the inspector refused to even look at what I had done. Nobody from work place of work wanted to look at it either. That by far was the worse working conditions I had ever worked in.
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