Ohio Revised Code Title XV. Conservation of Natural Resources § 1567.27

No employee in a mine, who is about to fire a shot with a squib, shall shorten the fuse, saturate it with oil, or ignite it, except at the extreme end; he shall see that all persons are out of danger from the probable effects of such shot, and if it is a rib shot, he shall notify the persons working next to him on said rib before firing said shot, and shall take measures to prevent anyone approaching by shouting “fire” immediately before lighting the fuse. When a squib is used and a shot misses fire, no person shall return until five minutes have elapsed.

When a fuse is used and a shot misses fire, no person shall return until one hour has elapsed for each foot of fuse used.

The needle used in preparing a blast shall be made of copper, and the tamping bar shall be made of wood, or shall be tipped with at least five inches of solid copper.

No inflammable material, explosive in its nature, or any material that may create a spark, shall be used for tamping, and some soft material must always be placed next to the cartridge or explosive. When it is necessary to tamp dynamite, nothing but a wooden tamper shall be used.

Two or more shots shall not be fired in the same face, unless all fuses used are at least twelve inches different in length, or unless the shots are fired simultaneously by electric caps or electric squibs.