Applies to caisson work, with specific triggers for compressed-air caissons. Where compressed air is in use, the working chamber is under 11 feet long, and the caisson is at any time suspended or hung during work so that the excavation bottom lies more than 9 feet below the working chamber deck, the employer must erect a shield inside to protect workers. Shafts must pass a hydrostatic or air-pressure test and be tight at the test pressure; each shaft is stamped on its outer shell roughly 12 inches from every flange with the pressure it was tested to. Where a shaft is used and space allows, it needs a safe, suitable staircase along its full length with landing platforms spaced no more than 20 feet apart. If a staircase is impracticable, suitable ladders are installed instead, with landings roughly every 20 feet so the climb is broken up. Any caisson whose diameter or side exceeds 10 feet must have a man lock and shaft reserved exclusively for employees. Beyond the gauge fitted in the locks, an accurate gauge is kept on both the outer and inner face of every bulkhead; these gauges must be reachable at all times and kept accurate and working. Where employees work in compressed air within caisson operations, all of the compressed air requirements in 1926.803 also apply, including medical supervision, lock design, compression and decompression limits and the Appendix A decompression tables.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.