A.All explosives shall be of the permissible type except where addressed in the plan for shaft and slope development required by subsection B of § 45.2-704.
B.All explosives shall be used as follows:
1.Explosives shall be fired only with electric detonators of proper strength;
2.Explosives shall be fired with permissible shot-firing units, unless firing is done from the surface when all persons are out of the mine, or in accordance with a plan approved by the Chief;
3.Where the coal is cut, no borehole in coal shall be drilled beyond the limits of the cut or into the roof or floor;
4.Every borehole shall be cleaned and checked to ensure that it is placed properly and is of the correct depth in relation to the cut before being charged;
5.Every blasting charge in coal shall have
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A. All explosives shall be of the permissible type except where addressed in the plan for shaft and slope development required by subsection B of § 45.2-704.
B. All explosives shall be used as follows:
1. Explosives shall be fired only with electric detonators of proper strength;
2. Explosives shall be fired with permissible shot-firing units, unless firing is done from the surface when all persons are out of the mine, or in accordance with a plan approved by the Chief;
3. Where the coal is cut, no borehole in coal shall be drilled beyond the limits of the cut or into the roof or floor;
4. Every borehole shall be cleaned and checked to ensure that it is placed properly and is of the correct depth in relation to the cut before being charged;
5. Every blasting charge in coal shall have a burden of at least 18 inches in every direction if the height of the coal permits;
6. Every borehole shall be stemmed with at least 24 inches of incombustible material, or at least one-half of the length of the hole shall be stemmed if the hole is less than four feet in depth. The Chief may approve the use of other stemming devices;
7. An examination for gas shall be made immediately before firing each shot or group of shots and after blasting is completed;
8. No shot shall be fired in any place where a methane level of one percent or greater can be detected with a permissible methane detector as directed by the Chief;
9. Without approval, no charge of greater than one and one-half pounds shall be used unless (i) each borehole is six feet or more in depth; (ii) the explosives are charged in a continuous train, with no cartridges deliberately deformed or crushed; (iii) all cartridges are in contact with each other, with the end cartridges touching the back of the hole and the stemming, respectively; and (iv) explosives permissible pursuant to this article are used. No charge exceeding three pounds shall be used; however, such three-pound limit shall not apply to solid rock work;
10. Any solid shooting shall be done in compliance with conditions prescribed by the Chief;
11. Any shot shall be fired by a certified underground shot firer;
12. No borehole shall be charged while any other work is being done at the face, and any shot shall be fired before any other work is done in the zone of danger from blasting except that which is necessary to safeguard the miners;
13. Only nonmetallic tamping bars, including a nonmetallic tamping bar with a nonsparking metallic scraper on one end, shall be used for charging and tamping boreholes;
14. The leg wires of every electric detonator shall be kept shunted until ready to connect to the firing cable;
15. The roof and faces of each working place shall be tested before and after firing each shot or group of shots;
16. Ample warning shall be given before any shot is fired, and care shall be taken to ascertain that all miners are in the clear;
17. Every miner shall be removed to a distance of at least 100 feet from the working place and any immediately adjoining working place and shall be accounted for before any shot is fired;
18. No mixed types or brands of explosives shall be charged or fired in any borehole;
19. No adobe, mudcap, or other open, unconfined shot shall be fired in any mine except a type approved by MSHA and the Chief;
20. Any power wire or cable that could contact any blasting cable or leg wire shall be de-energized during charging and firing;
21. Firing a shot from a properly installed and protected blasting circuit may be permitted by the Chief;
22. No miner shall return or be allowed to return to the working place after the firing of any shot until the smoke has reasonably cleared away;
23. Before any miner returns to work and begins to load coal, slate, or refuse, such miner shall make a careful examination of the condition of the roof and do what is necessary to make the working place safe; and
24. An examination for fire shall be made of the working area after any blasting.
C. It is unlawful for an operator, his agent, or a mine foreman to cause or permit any solid shooting to be done without first obtaining a written permit from the Chief. It is unlawful for any miner to shoot coal from the solid without first obtaining permission to do so from the operator, his agent, or a mine foreman. A violation of this subsection is a Class 1 misdemeanor.