Provides instructions, principally of a technical nature, for the manufacturer, user and repairer on the repair, overhaul, reclamation and modification of a certified apparatus as well as additional requirements for the repair and overhaul of an apparatus with types of protection "d" (flameproof), "i" (intrinsic safety), "p" (pressurized), "e" (increased safety), and "n" (non-sparking).