§ 33.32. Signal system.

 (a)  Requirement. Unless the engineer has a full view of the load at all times, every hoisting engine and every lookout or signalman operating at a pit or quarry shall have an efficient signal system. No hoisting engine shall be operated when the signal system is out of order unless the engineer has a full view of the load. In deep pit quarries calling shall not be accepted as a method of signaling. The custom of placing a man on the bank to signal by waving his hands to the engineer is prohibited.

 (b)  Location. Each signal system operated in connection with a hoisting engine shall be so constructed and located as to be audible and visible to the hoisting engineer at all times.

 (c)  Posting of code. The signal code in use in a pit or quarry shall be prominently posted in the engineroom within easy sight of the hoisting engineer. It shall also be posted in the lookout house and at all other places from which signals are given whenever practicable. These signal codes shall be printed in heavy plain type.