Subchapter 7. General Industry Safety Orders
Group 18. Explosives and Pyrotechnics
Article 114. Storage of Explosives

§5253.1. Construction and Use of Magazines

(a) Type 1 Magazines.

(1) A Type 1 magazine shall be a permanent structure; a building, igloo, tunnel, or dugout. It shall be bullet, theft, fire and weather resistant, and be well ventilated.

(A) A Type 1 magazine shall be built at least equivalent to one of the following methods:

1. 8 inch masonry.

2. Metal of at least 14 gauge.

3. Wood frame with at least 26-gauge metal covering. No wood shall be exposed on the exterior.

(B) A Type 1 magazine shall meet the following additional requirements.

1. Masonry in subsection (a)(1)(A)1. shall have any openings in tile or cement blocks filled with a coarse, dry sand or a wet mixture of 1 part cement and 10 parts dry sand.

2. Metal in subsections (a)(1)(A)2. and 3. above shall be lined inside with not less than 4 inches of brick, solid cement blocks, hardwood, or equivalent.

(C) Solid wood or plywood floors are required. Floors shall be strong enough to bear the weight of the maximum quantity to be stored.

(D) Magazines shall have no openings except for ventilation and entrances. Vent openings shall be screened to prevent sparks passing through them.

(E) Magazine roofs shall be constructed of at least 7/8-inch sheathing covered with not less than 26-gauge iron or aluminum. Where it is possible for a bullet to be fired directly through the roof and into the magazine at such an angle that the bullet would strike the explosives within, the magazine is to be protected by one of the following methods:

1. A sand tray lined with a layer of building paper, plastic or other nonporous material, and filled with not less than four inches of coarse, dry sand, and located at the tops of inner walls covering the entire ceiling area, except the portion necessary for ventilation, or

2. A fabricated metal roof constructed of 3/16 inch plate steel lined with four inches of hardwood. (For each additional 1/16 inch of plate steel, the hardwood lining may be decreased one inch.)

(F) Magazine doors shall be kept closed and locked, except when opened for transacting business. The magazine doors shall be constructed of at least 1/4 inch plate steel on the outside and lined with at least two inches of hardwood on the inside.

(G) Each door shall be equipped with:

1. Two mortise locks; or

2. Two padlocks fastened in separate hasps and staples; or

3. A combination of a mortise lock and padlock; or

4. A mortise lock that requires two keys to open; or

5. A three-point lock.

6. If padlocks are used, they shall have at least five tumblers and a case-hardened shackle of at least 3/8 inch diameter. Padlocks shall be protected with not less than 1/4 inch steel hoods constructed so as to prevent sawing or lever action on the locks, hasps, and staples.

Exception: The lock requirement does not apply to magazine doors that are adequately secured on the inside by means of a bolt, lock, or bar that cannot be actuated from the outside.

(b) Type 2 Magazines.

(1) A Type 2 magazine shall be a portable box, trailer, semitrailer, or other mobile facility. It shall be bullet, theft, fire, and weather resistant, and shall be well ventilated. It shall be supported to prevent direct contact with the ground and, if less than one cubic yard in size, shall be securely fastened to a fixed object.

(A) The exterior construction and doors shall be constructed of not less than 1/4 inch steel and lined with at least two inches of hardwood. Magazines with top openings shall have lids with water-resistant seals or, lids that overlap the sides by at least one inch when in the closed position.

(B) Hinges and hasps shall be attached to doors by welding, riveting, or bolting (nut on inside of door). Hinges and hasps shall be installed so that they cannot be removed when the doors are closed and locked.

(C) Doors shall be equipped with locks as required by Section 5253.1(a)(1)(G).

(D) Type 2 magazines shall be located in conformity with Table EX-1, Distances for the Storage of Explosives, but may be permitted in warehouses and in wholesale and retail establishments when located on a floor which has an exit outside at grade level and the magazine is located not more than 10 feet from such an exit. Two Type 2 magazines may be located in the same building when one is used only for blasting caps in quantities not in excess of 5,000 caps and a distance of 10 feet is maintained between magazines.

(E) Indoor magazines shall be painted “red” and shall bear lettering in “white” on sides and top at least 3 inches high with a 1/2 inch stroke which reads, EXPLOSIVES--KEEP FIRE AWAY”.

Exception: When size of the indoor magazine does not permit, letterings shall be as large as possible.

(c) Type 3 Magazines.

(1) A Type 3 magazine is a “Day Box” or other portable magazine. It shall be fire, theft and weather resistant. A Type 3 magazine shall be constructed of not less than number 12 gauge steel lined with a minimum of either 1/2 inch plywood or 1/2 inch Masonite-type hardboard.

(A) The door or lid shall overlap the opening by at least one inch. Hinges and hasps shall be attached by welding, riveting or bolting (nuts on inside of door).

(B) At least one steel padlock shall be provided (which need not be protected by a steel hood) having at least five tumblers and a case-hardened shackle of at least 3/8 inch diameter.

(2) When used for temporary storage at a site for blasting operations, Type 3 magazines shall be located away from inhabited buildings, and other magazines. A distance of at least 150 feet shall be maintained between Type 3 magazines and the other work in progress.

(d) Type 4 Magazines.

(1) A Type 4 magazine shall be a building, igloo, tunnel, dugout, box, trailer, semi-trailer, or other mobile magazine. It shall be fire, theft and weather resistant.

(A) A Type 4 magazine shall be constructed of masonry, metal-covered wood, fabricated metal, or a combination of these materials. The foundation shall be constructed of brick, concrete, cement block, stone, or metal or wood posts. If piers or posts are used in lieu of a continuous foundation, the space under the building shall be enclosed with fire-resistant material. The walls and floor shall be constructed of, or covered with nonsparking material or lattice work.

(B) The doors shall be metal or solid wood covered with metal. Hinges and hasps shall be attached by welding, riveting or bolting (nuts on inside of the door). Hinges and hasps shall be installed so that they cannot be removed when the doors are closed and locked.

(C) Locks shall meet the requirements of Section 5253.1(a)(1)(G).

(e) Type 5 Magazines.

(1) A Type 5 magazine shall be a building, igloo, tunnel, dugout, box, trailer, semi-trailer, or other mobile magazine. It shall be theft and weather resistant.

(A) The doors shall be metal or solid wood covered with metal. Hinges and hasps shall be attached by welding, riveting or bolting (nuts on inside of the door). Hinges and hasps shall be installed so that they cannot be removed when the doors are closed and locked.

(B) Locks shall meet the requirements of Section 5253.1(a)(1)(G).

(f) Magazines shall be ventilated to minimize dampness and heating of stored explosives. ventilation openings shall be screened with 14 mesh, 21-gauge wire to prevent the entrance sparks and rodents, and shall be protected in a manner that will maintain the bullet resistance of the magazine.

NOTE: The recommendation for ventilation as contained in Safety Library Publication No. 1, Institute of Makers of Explosives, 1993 Edition, is evidence of good practice.

NOTE

Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.

HISTORY

1. New section filed 7-11-2003; operative 8-10-2003 (Register 2003, No. 28).