Provides rules relating to working procedures and to safety and health of persons working in compressed air in tunnels, shafts and pneumatic caissons for pressures up to 50 lbf/in(sup)2, but does not include diving. Sections deal with medical supervision (including requirements for medical officers, medical orderlies and first-aid personnel), operation, equipment and general precautions, and appendices provide details of medical standards for workers in compressed air, instructions ' decompression sickness and its treatment, limits on flying or diving after work in compressed air, and decompression tables for the range of pressures covered.