SECTION 265:20-1-9. Barrier  


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  •   Properly constructed separated artificial or substantial natural barricades are effective means for protecting structures or operations, thereby permitting reduction of quantity-distance requirements of bulk explosives and explosives-loaded items having mass-detonating characteristics. General rules concerning barricades are listed below.
    (1)   Barricades are ineffective and shall not be used to reduce distances for fire hazard materials (propellants), missile producing items (projectiles, mines, rocket motors) or more than 250,000 net pounds of Class "A" explosives.
    (2)   Protection is considered effective when a line drawn from the top of any side-wall of the explosives building or magazine to all parts of the other locations to be protected will pass through the intervening barricade.
    (3)   For railroads and highways to be considered effectively screened by a barricade, such a line must pass 12 feet above the center of the highway or railroad.
    (4)   A barricade must be separated from the building, magazine containing the explosives. The nearest toe of the barricade must not be less than four (4) feet nor more than 40 feet from such building, magazine or truck. A barricade may be located adjacent to the structure being protected and the same minimum and maximum distance shall apply.
    (5)   The slope of the sides of a barricade may be decreased by rivetting with either wood or concrete, well braced to prevent collapse and possible injury to personnel.
    (6)   Barricades may be natural or artificial earth mounds having natural sloping sides, or single rivetted with either wood or concrete and having a natural slope on one side. The earth mound shall be a minimum width of three (3) feet at the top. Barricades in excess of twenty (20) feet in height will have a minimum width of five (5) feet at the top. Double rivetted artificial barricades with a minimum width of three (3) feet at the top with sides sloped and with proper anchorage to give stability against overturning forces are approved for having quantity-distance requirements for a maximum of 50,000 net pounds of explosives. For quantities in excess of 50,000 net pounds, natural or single-rivetted barricades as described above are the only types approved.
    (7)   Reinforced concrete barricades, fifteen (15) inches wide at the top as a minimum, with faces having a slope of one to four may be used for reducing quantity-distance separations by one-half when the quantities of bulk high explosives and explosive-filled items having mass detonating characteristics do not exceed 5,000 net pounds of explosives.
    (8)   The earth fill for artificial barricades shall be a select cohesive material, free from deleterious organic matter, trash, debris, frozen material and stones heavier than 10 pounds or larger than six inches. The larger stones should be predominantly limited to the lower center of fills. Compaction and surface preparation shall be provided as necessary to maintain structural integrity and erosion protection. Barricades are intended to protect against the blast damage effects of explosion but not against missile hazards of fire-exposure hazards.
    (9)   "Barricaded" means that a building containing explosives is effectively 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 twelve feet above the center of a railway or highway, will pass through such intervening natural or artificial barricade.
    (10)   "Natural barricade" means natural features of the ground, such as hills, or timber or sufficient density that the surrounding exposures which require protection cannot be seen from the magazine when the trees are bare of leaves.
    (11)   "Artificial barricade" means natural an artificial mound or rivetted wall of earth of a minimum thickness of three feet.
    (12)   When a building or magazine containing explosives is not barricaded, the distances shown in the Table shall be doubled.
    (13)   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 distance 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 magazine 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.
    (14)   The permanent storage of more than 250,000 pounds of commercial explosives in one magazine or in a group of magazines which is considered as one magazine is not permitted except by specific approval of the enforcing official.
    (15)   This table applies only to the manufacture and 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.
    (16)   All types of blasting caps in strengths through No. 8 caps shall be treated at one and one-half (1-1/2) pounds of explosives per 1,000 caps. For strengths higher than No. 8 cap, consult the authority having jurisdiction.
    (17)   For quantity-distance purposes, detonating fuse should be calculated as equivalent to 10 pounds of high explosive per 1,000 feet.
    (18)   If at any time the distance from a magazine to the nearest building, highway or railroad is decreased through the construction of a new building, highway or railroad, the quantity of explosives kept or stored in the magazine shall be reduced to correspond with that specified for the new distance by the quantity-distance table. The quantity need not be reduced, however, in the event that a new building is constructed in bad faith and with the intent to annoy, harass, oppress, or hinder the owner of the magazine.