WAC 296-52-67075. Blast area precautions

(1) Warning signs. Blast area warning signs must: (a) Be set up at all entrances to the blast area. (b) Have lettering a minimum of four inches high and on a contrasting background. (2) Loaded stumps. All loaded stumps must be marked for identification. (3) Lock out. Cables close to the blast area must be deenergized and locked out by the blaster in charge.