WAC 296-52-67235. Firing the blast

(1) Employee evacuation. The blaster must make sure all employees are out of the blast area before firing a blast. (2) Guarding entrances. All entrances: (a) Leading into the blasting area must be carefully guarded. (b) To any working place where a drift, raise, or other opening is about to hole through must be carefully guarded. (3) Warning signals. A warning must be given before firing an underground blast. See Table T-1 for signaling requirements. TABLE T-1 warning signal A 1 minute series of long blasts 5 minutes prior to blast signal. blast signal A series of short blasts 1 minute prior to the shot. all clear signal A prolonged blast following the inspection of the blast. TABLE T-1 warning signal A 1 minute series of long blasts 5 minutes prior to blast signal. blast signal A series of short blasts 1 minute prior to the shot. all clear signal A prolonged blast following the inspection of the blast.