Current through Register Vol. 54, No. 50, December 14, 2024
(a) Every shaft shall be provided with an efficient means of interchanging distinct and definite signals between the top of the shaft and the lowest level and the intermediate levels from which hoisting is being done. After sinking operations have been completed and before tunneling operations are begun from any shaft, there shall be provided and maintained two separate systems of signaling, which shall be either electrical, pneumatic, or mechanical, or one such system supplemented by a speaking tube or telephone.(b) No person shall knowingly interfere with or impede a signal, or damage a signal system, or give cause for a wrong signal to be given.(c) No signal shall be given to the hoisting engineer to raise or lower any car, cage, skip or bucket unless the signalman is at the same level occupied by that car, cage, skip or bucket.(d) The following code of signals shall be used:(1) One bell-Stop if in motion, or hoist if not in motion.(3) Three bells-Men on, run very carefully.(e) Additional signals to meet local conditions may be used, if they are easily distinguishable and do not conflict with subsection (d). In shafts where there are intermediate levels, means shall be provided for preventing conflict of signals from the different levels.(f) An easily legible copy of the requirement in subsection (d) and of any special code adopted in any shaft or tunnel, shall be secureley posted in the engineroom, at the collar of the shaft, and at each level or station. Each copy shall be printed in letters at least 1/2 inch high, on a board or metal plate at least 18 inches by 18 inches.