Section 77.1600 - Loading and haulage; general(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.