(a) Only authorized persons shall be permitted on haulage roads and
at loading or dumping locations.
(b) Traffic rules, signals, and warning signs shall be standardized
at each mine and posted.
(c) Where side or overhead clearances on any haulage road or at any
loading or dumping location at the mine are hazardous to mine workers, such
areas shall be conspicuously marked and warning devices shall be installed
when necessary to insure the safety of the workers.