S-2.1, r. 4 - Safety Code for the construction industry

Section 4.6.9.1 Disposition versions

2015-02-26

4.6.9.1. Conditions for untamping and repriming a blasthole or misfire: Prior to the untamping or repriming of a blasthole or misfire, the employer must prepare a written procedure that takes into account the types of explosives and the manufacturer’s instructions in that regard, as well as environmental conditions.

The employer must also make sure that

(a)  the procedure is available on the construction site;

(b)  the untamping of the collar is done by the shot-firer who loaded and fired the blasthole, unless it is impossible for him to do so;

(c)  during all untamping, repriming and firing operations, all persons except the shot-firer are outside the blasting area;

(d)  the constituents of the material used for untamping the blasthole and inserted in it is made of non-ferrous materials.

R.R.Q., 1981, c. S-2.1, r. 6, s. 4.6.9.1; O.C. 1959-86, s. 56; O.C. 57-2015, s. 40.

2012-09-01

4.6.9.1. Conditions for untamping and refiring a blasthole or misfire:

(a)  Where dynamite is used, a protective buffer 100 mm thick, inserted between the explosive load and the regular tamping, must be put in place when loading the blasthole. Otherwise, untamping of the blasthole is strictly prohibited in all circumstances. The protective buffer may be made either of brightly coloured paper contrasting with the colour of the rock, the wrapping of the explosive and the tamping used, or of any other device having the same effectiveness;

(b)  untamping must be performed by the shot-firer who loaded and fired the blasthole;

(c)  during all operations of untamping, repriming and refiring of a blasthole or misfire, the shot-firer must ensure that the workers have taken shelter;

(d)  the method used for untamping must never produce stress and shock for the protective buffer and the explosive;

(e)  the constituents of the materials used for untamping the blasthole and inserted in it must be made of non-ferrous material;

(f)  untamping must be stopped as soon as the protective buffer is reached, a primed explosive cartridge is then inserted against the protective buffer, and the blasthole is obturated again by a tamping similar to the previous one;

(g)  untamping is prohibited when the blasthole is obturated by a self-taping device; and

(h)  the holes loaded with nitrocarbonitrates such as ANFO must be washed completely before repriming them with a new primer cartridge.

R.R.Q., 1981, c. S-2.1, r. 6, s. 4.6.9.1; O.C. 1959-86, s. 56.