(1) Moving parts of machines shall be protected by safety devices. They shall be designed, constructed and used so as:
(a) to ensure a positive protection and to prevent any access to the danger zone during their operation;
(b) not to hamper the operator;
(c) to operate automatically or with a minimum of effort;
(d) to allow easy maintenance and repair of the machine;
(e) not to have sharp edges, asperities or burrs and to constitute a source of hazards; and
(f) to be solidly fixed.
(2) If moving parts are not protected due to their location or by suitable guards, it shall be assured that:
(a) the projecting extremities of transmission shafts are protected by sleeves or sockets;
(b) the revolving collars are cylindrical and without projecting parts;
(c) the jet screws, belts, keys, grease cups and other projections in revolving parts are flushed or covered to avoid any contact; and
(d) unused keyways are filled up or enclosed in a guard.