Special signals in addition to the above, or signals in lieu thereof, may be used in any mine, provided they are easily distinguishable by their sound or otherwise, and do not interfere with them in any way.
225 ILCS 710/45.17
Special signals in addition to the above, or signals in lieu thereof, may be used in any mine, provided they are easily distinguishable by their sound or otherwise, and do not interfere with them in any way.
225 ILCS 710/45.17