All Class A, Class B, Class C explosives, and special industrial explosives, and any newly developed and unclassified explosives, shall be kept in magazines which meet the requirements of this paragraph.
Ground around magazines shall slope away for drainage. The land surrounding magazines shall be kept clear of brush, dried grass, leaves, and other materials for a distance of at least 25 feet.
Magazines as required by this paragraph shall be of two classes; namely, Class I magazines, and Class II magazines.
This paragraph (c) does not apply to:
Stocks of small arms ammunition, propellant-actuated power cartridges, small arms ammunition primers in quantities of less than 750,000, or of smokeless propellants in quantities less than 750 pounds;
Explosive-actuated power devices when in quantities less than 50 pounds net weight of explosives;
Fuse lighters and fuse igniters;
Safety fuses other than cordeau detonant fuses.
Class I magazines shall be required where the quantity of explosives stored is more than 50 pounds. Class II magazines may be used where the quantity of explosives stored is 50 pounds or less.
Class I magazines shall be located away from other magazines in conformity with Table H-21.
Footnote(1) "Natural barricade" means natural features of the
ground, such as hills, or timber of sufficient density that the
surrounding exposures which require protection cannot be seen from
the magazine when the trees are bare of leaves.
Footnote(2) "Artificial barricade" means an artificial mound or
revetted wall of earth of a minimum thickness of three feet.
Footnote(3) "Barricaded" means that a building containing
explosives is effectually screened from a magazine, building,
railway, or highway, either by a natural barricade, or by an
artificial barricade of such height that a straight line from the top
of any sidewall of the building containing explosives to the eave
line of any magazine, or building, or to a point 12 feet above the
center of a railway or highway, will pass through such intervening
natural or artificial barricade.
Footnote(4) When two or more storage magazines are located on the
same property, each magazine must comply with the minimum distances
specified from inhabited buildings, railways, and highways, and in
addition, they should be separated from each other by not less than
the distances shown for "Separation of Magazines," except that the
quantity of explosives contained in cap magazines shall govern in
regard to the spacing of said cap magazines from magazines containing
other explosives. If any two or more magazines are separated from
each other by less than the specified "Separation of Magazines"
distances, then such two or more magazines, as a group, must be
considered as one magazine, and the total quantity of explosives
stored in such group must be treated as if stored in a single
magazine located on the site of any magazine of the group, and must
comply with the minimum of distances specified from other magazines,
inhabited buildings, railways, and highways.
Footnote(5) This table applies only to the permanent storage of
commercial explosives. It is not applicable to transportation of
explosives, or any handling or temporary storage necessary or incident
thereto. It is not intended to apply to bombs, projectiles, or other
heavily encased explosives.
| Explosives | Distances in feet when storage is barricaded: Separation of magazines |
|
| Pounds over | Pounds not over | |
| 2 | 5 | 6 |
| 5 | 10 | 8 |
| 10 | 20 | 10 |
| 20 | 30 | 11 |
| 30 | 40 | 12 |
| 40 | 50 | 14 |
| 50 | 75 | 15 |
| 75 | 100 | 16 |
| 100 | 125 | 18 |
| 125 | 150 | 19 |
| 150 | 200 | 21 |
| 200 | 250 | 23 |
| 250 | 300 | 24 |
| 300 | 400 | 27 |
| 400 | 500 | 29 |
| 500 | 600 | 31 |
| 600 | 700 | 32 |
| 700 | 800 | 33 |
| 800 | 900 | 35 |
| 900 | 1,000 | 36 |
| 1,000 | 1,200 | 39 |
| 1,200 | 1,400 | 41 |
| 1,400 | 1,600 | 43 |
| 1,600 | 1,800 | 44 |
| 1,800 | 2,000 | 45 |
| 2,000 | 2,500 | 49 |
| 2,500 | 3,000 | 52 |
| 3,000 | 4,000 | 58 |
| 4,000 | 5,000 | 61 |
| 5,000 | 6,000 | 65 |
| 6,000 | 7,000 | 68 |
| 7,000 | 8,000 | 72 |
| 8,000 | 9,000 | 75 |
| 9,000 | 10,000 | 78 |
| 10,000 | 12,000 | 82 |
| 12,000 | 14,000 | 87 |
| 14,000 | 16,000 | 90 |
| 16,000 | 18,000 | 94 |
| 18,000 | 20,000 | 98 |
| 20,000 | 25,000 | 105 |
| 25,000 | 30,000 | 112 |
| 30,000 | 35,000 | 119 |
| 35,000 | 40,000 | 124 |
| 40,000 | 45,000 | 129 |
| 45,000 | 50,000 | 135 |
| 50,000 | 55,000 | 140 |
| 55,000 | 60,000 | 145 |
| 60,000 | 65,000 | 150 |
| 65,000 | 70,000 | 155 |
| 70,000 | 75,000 | 160 |
| 75,000 | 80,000 | 165 |
| 80,000 | 85,000 | 170 |
| 85,000 | 90,000 | 175 |
| 90,000 | 95,000 | 180 |
| 95,000 | 100,000 | 185 |
| 100,000 | 110,000 | 195 |
| 110,000 | 120,000 | 205 |
| 120,000 | 130,000 | 215 |
| 130,000 | 140,000 | 225 |
| 140,000 | 150,000 | 235 |
| 150,000 | 160,000 | 245 |
| 160,000 | 170,000 | 255 |
| 170,000 | 180,000 | 265 |
| 180,000 | 190,000 | 275 |
| 190,000 | 200,000 | 285 |
| 200,000 | 210,000 | 295 |
| 210,000 | 230,000 | 315 |
| 230,000 | 250,000 | 335 |
| 250,000 | 275,000 | 360 |
| 275,000 | 300,00 | 385 |
ground, such as hills, or timber of sufficient density that the
surrounding exposures which require protection cannot be seen from
the magazine when the trees are bare of leaves.
Footnote(2) "Artificial barricade" means an artificial mound or
revetted wall of earth of a minimum thickness of three feet.
Footnote(3) "Barricaded" means that a building containing
explosives is effectually screened from a magazine, building,
railway, or highway, either by a natural barricade, or by an
artificial barricade of such height that a straight line from the top
of any sidewall of the building containing explosives to the eave
line of any magazine, or building, or to a point 12 feet above the
center of a railway or highway, will pass through such intervening
natural or artificial barricade.
Footnote(4) When two or more storage magazines are located on the
same property, each magazine must comply with the minimum distances
specified from inhabited buildings, railways, and highways, and in
addition, they should be separated from each other by not less than
the distances shown for "Separation of Magazines," except that the
quantity of explosives contained in cap magazines shall govern in
regard to the spacing of said cap magazines from magazines containing
other explosives. If any two or more magazines are separated from
each other by less than the specified "Separation of Magazines"
distances, then such two or more magazines, as a group, must be
considered as one magazine, and the total quantity of explosives
stored in such group must be treated as if stored in a single
magazine located on the site of any magazine of the group, and must
comply with the minimum of distances specified from other magazines,
inhabited buildings, railways, and highways.
Footnote(5) This table applies only to the permanent storage of
commercial explosives. It is not applicable to transportation of
explosives, or any handling or temporary storage necessary or incident
thereto. It is not intended to apply to bombs, projectiles, or other
heavily encased explosives.
Except as provided in subdivision (viii) of this subparagraph, class II magazines shall be located in conformity with Table H-21, but may be permitted in warehouses and in wholesale and retail establishments when located on a floor which has an entrance at outside grade level and the magazine is located not more than 10 feet from such an entrance. Two class II 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.
When used for temporary storage at a site for blasting operations, class II magazines shall be located away from other magazines. A distance of at least one hundred and fifty (150) feet shall be maintained between class II magazines and the work in progress when the quantity of explosives kept therein is in excess of 25 pounds, and at least 50 feet when the quantity of explosives is 25 pounds, or less.
Blasting caps, electric blasting caps, detonating primers, and primed cartridges shall not be stored in the same magazine with other explosives.
Magazines shall be constructed in conformity with the provisions of this paragraph.
Property upon which Class I magazines are located and property where Class II magazines are located outside of buildings shall be posted with signs reading "Explosives-Keep Off."
Magazines requiring heat shall be heated by either hot-water radiant heating with the magazine building; or air directed into the magazine building over either hot water or low pressure steam (15 p.s.i.g.) coils located outside the magazine building.
The magazine heating systems shall meet the following requirements:
The radiant heating coils within the building shall be installed in such a manner that the explosives or explosives containers cannot contact the coils and air is free to circulate between the coils and the explosives or explosives containers.
The heating ducts shall be installed in such a manner that the hot-air discharge from the duct is not directed against the explosives or explosives containers.
The heating device used in connection with a magazine shall have controls which prevent the ambient building temperature from exceeding 130 deg. F.
The electric fan or pump used in the heating system for a magazine shall be mounted outside and separate from the wall of the magazine and shall be grounded.
The electric fan motor and the controls for electrical heating devices used in heating water or steam shall have overloads and disconnects, which comply with subpart S of this part. All electrical switch gear shall be located a minimum distance of 25 feet from the magazine.
The heating source for water or steam shall be separated from the magazine by a distance of not less than 25 feet when electrical and 50 feet when fuel fired. The area between the heating unit and the magazine shall be cleared of all combustible materials.
The storage of explosives and explosives containers in the magazine shall allow uniform air circulation so product temperature uniformity can be maintained.
When lights are necessary inside the magazine, electric safety flashlight, or electric safety lanterns shall be used.
Magazines for the storage of explosives, other than black powder, Class B and Class C explosives shall be bullet resistant, weather resistant, fire resistant, and ventilated sufficiently to protect the explosive in the specific locality. Magazines used only for storage of black powder, Class B and Class C explosives shall be weather resistant, fire-resistant, and have ventilation. Magazines for storage of blasting and electric blasting caps shall be weather resistant, fire-resistant, and ventilated.
Class I magazines shall be of masonry construction or of wood or of metal construction, or a combination of these types. Thickness of masonry units shall not be less than 8 inches. Hollow masonry units used in construction required to be bullet resistant shall have all hollow spaces filled with weak cement or well-tamped sand. Wood constructed walls, required to be bullet resistant, shall have at least a 6-inch space between interior and exterior sheathing and the space between sheathing shall be filled with well-tamped sand. Metal wall construction, when required to be bullet resistant, shall be lined with brick at least 4 inches in thickness or shall have at least a 6-inch sandfill between interior and exterior walls.
Roofs required to be bullet resistant shall be protected by a sand tray located at the line of eaves and covering the entire area except that necessary for ventilation. Sand in the sand tray shall be maintained at a depth of not less than 4 inches.
All wood at the exterior of magazines, including eaves, shall be protected by being covered with black or galvanized steel or aluminum metal of thickness of not less than No. 26 gage. All nails exposed to the interior of magazines shall be well countersunk.
Provisions shall be made to prevent the piling of stocks of explosives directly against masonry walls, brick-lined or sand-filled metal walls and single-thickness metal walls; such protection, however, shall not interfere with proper ventilation at the interior of side and end walls.
Foundations for magazines shall be of substantial construction and arranged to provide good cross ventilation.
Magazines shall be ventilated sufficiently to prevent dampness and heating of stored explosives. Ventilating openings shall be screened to prevent the entrance of sparks.
Openings to magazines shall be restricted to that necessary for the placement and removal of stocks of explosives. Doors for openings in magazines for Class A explosives shall be bullet resistant. Doors for magazines not required to be bullet resistant shall be designed to prevent unauthorized entrance to the magazine.
Floors and roofs of masonry magazines may be of wood construction. Wood floors shall be tongue and grooved lumber having a nominal thickness of 1 inch.
Class II magazines shall be of wood or metal construction, or a combination thereof.
Covers for both wood- and metal-constructed magazines of this class shall be provided with substantial strap hinges and shall be provided with substantial means for locking.
Magazines of this class shall be painted red and shall bear lettering in white, on all sides and top, at least 3 inches high, "Explosives - Keep Fire Away." Class II magazines when located in warehouses, and in wholesale and retail establishments shall be provided with substantial wheels or casters to facilitate easy removal in the case of fire. Where necessary due to climatic conditions, Class II magazines shall be ventilated.
Wood magazines of this class shall have sides, bottom, and cover constructed of 2-inch hardwood boards well braced at corners and protected by being entirely covered with sheet metal of not less than No. 20 gage. All nails exposed to the interior of the magazine shall be well countersunk. All metal magazines of this class shall have sides, bottom, and cover constructed of sheet metal, and shall be lined with three-eighths-inch plywood or equivalent. Edges of metal covers shall overlap sides at least 1 inch.