- Part Number:1910
- Part Number Title:Occupational Safety and Health Standards
- Subpart:1910 Subpart H
- Subpart Title:Hazardous Materials
- Standard Number:
- Title:Explosives and blasting agents.
- GPO Source:
Definitions applicable to this section -
Blasting agent. Blasting agent - any material or mixture, consisting of a fuel and oxidizer, intended for blasting, not otherwise classified as an explosive and in which none of the ingredients are classified as an explosive, provided that the finished product, as mixed and packaged for use or shipment, cannot be detonated by means of a No. 8 test blasting cap when unconfined.
Explosive-actuated power devices. Explosive-actuated power device - any tool or special mechanized device which is actuated by explosives, but not including propellant-actuated power devices. Examples of explosive-actuated power devices are jet tappers and jet perforators.
Explosive. Explosive - any chemical compound, mixture, or device, the primary or common purpose of which is to function by explosion, i.e., with substantially instantaneous release of gas and heat, unless such compound, mixture, or device is otherwise specifically classified by the U.S. Department of Transportation; see 49 CFR chapter I. The term “explosives” shall include all material which is classified as Class A, Class B, and Class C explosives by the U.S. Department of Transportation, and includes, but is not limited to dynamite, black powder, pellet powders, initiating explosives, blasting caps, electric blasting caps, safety fuse, fuse lighters, fuse igniters, squibs, cordeau detonant fuse, instantaneous fuse, igniter cord, igniters, small arms ammunition, small arms ammunition primers, smokeless propellant, cartridges for propellant-actuated power devices, and cartridges for industrial guns. Commercial explosives are those explosives which are intended to be used in commercial or industrial operations.
Classification of explosives is described by the U.S. Department of Transportation as follows (see 49 CFR chapter I):
Class A explosives. Possessing, detonating, or otherwise maximum hazard; such as dynamite, nitroglycerin, picric acid, lead azide, fulminate of mercury, black powder, blasting caps, and detonating primers.
Class B explosives. Possessing flammable hazard, such as propellant explosives (including some smokeless propellants), photographic flash powders, and some special fireworks.
Class C explosives. Includes certain types of manufactured articles which contain Class A or Class B explosives, or both, as components but in restricted quantities.
Forbidden or not acceptable explosives. Explosives which are forbidden or not acceptable for transportation by common carriers by rail freight, rail express, highway, or water in accordance with the regulations of the U.S. Department of Transportation, 49 CFR chapter I.
Highway. Highway - any public street, public alley, or public road.
Magazine. Magazine - any building or structure, other than an explosives manufacturing building, used for the storage of explosives.
Motor vehicle. Motor vehicle - any self-propelled vehicle, truck, tractor, semitrailer, or truck-full trailers used for the transportation of freight over public highways.
Propellant-actuated power devices. Propellant-actuated power devices - any tool or special mechanized device or gas generator system which is actuated by a smokeless propellant or which releases and directs work through a smokeless propellant charge.
Pyrotechnics. Pyrotechnics - any combustible or explosive compositions or manufactured articles designed and prepared for the purpose of producing audible or visible effects which are commonly referred to as fireworks.
Semiconductive hose. Semiconductive hose - a hose with an electrical resistance high enough to limit flow of stray electric currents to safe levels, yet not so high as to prevent drainage of static electric charges to ground; hose of not more than 2 megohms resistance over its entire length and of not less than 5,000 ohms per foot meets the requirement.
Small arms ammunition. Small arms ammunition - any shotgun, rifle, pistol, or revolver cartridge, and cartridges for propellant-actuated power devices and industrial guns. Military-type ammunition containing explosive-bursting charges, incendiary, tracer, spotting, or pyrotechnic projectiles is excluded from this definition.
Small arms ammunition primers. Small arms ammunition primers - small percussion-sensitive explosive charges, encased in a cup, used to ignite propellant powder.
Smokeless propellants. Smokeless propellants - solid propellants, commonly called smokeless powders in the trade, used in small arms ammunition, cannon, rockets, propellant-actuated power devices, etc.
Special industrial explosives devices. Special industrial explosives devices - explosive-actuated power devices and propellant-actuated power devices.
Special industrial explosives materials. Special industrial explosives materials - shaped materials and sheet forms and various other extrusions, pellets, and packages of high explosives, which include dynamite, trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), hexahydro-1,3,5-trinitro-s-triazine (RDX), and other similar compounds used for high-energy-rate forming, expanding, and shaping in metal fabrication, and for dismemberment and quick reduction of scrap metal.
Water gels or slurry explosives. These comprise a wide variety of materials used for blasting. They all contain substantial proportions of water and high proportions of ammonium nitrate, some of which is in solution in the water. Two broad classes of water gels are
those which are sensitized by a material classed as an explosive, such as TNT or smokeless powder,
those which contain no ingredient classified as an explosive; these are sensitized with metals such as aluminum or with other fuels. Water gels may be premixed at an explosives plant or mixed at the site immediately before delivery into the borehole.
DOT specifications. Regulations of the Department of Transportation published in 49 CFR chapter I.
Miscellaneous provisions -
General hazard. No person shall store, handle, or transport explosives or blasting agents when such storage, handling, and transportation of explosives or blasting agents constitutes an undue hazard to life.
Storage of explosives -
Class I magazines shall be located away from other magazines in conformity with Table H-21.
Table H-21 - American Table of Distances for Storage of Explosives1-5
[As revised and approved by the Institute of Makers of Explosives, June 5, 1964]
|Explosives||Distances in feet when storage is barricaded: Separation of magazines|
|Pounds over||Pounds not over|
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.
2 “Artificial barricade” means an artificial mound or revetted wall of earth of a minimum thickness of three feet.
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.
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.
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.
Construction of magazines - general.
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.”
The heating device used in connection with a magazine shall have controls which prevent the ambient building temperature from exceeding 130 °F.
Construction of Class I magazines.
Construction of Class II magazines.
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.
Storage within magazines.
Transportation of explosives -
Exterior markings or placards required on applicable vehicles shall be as follows for the various classes of commodities:
|Commodity||Type of marking or placard|
|Explosives, Class A, any quantity or a combination of Class A and Class B explosives||Explosives A (Red letters on white background).|
|Explosives, Class B, and quantity||Explosives B (Red letters on white background).|
|Oxidizing material (blasting agents, ammonium nitrate, etc.), 1,000 pounds or more gross weight||Oxidizers (Yellow letters on black background).|
Any motor vehicle, trailer, or other cargo-carrying body containing more than one kind of explosive as well as an oxidizing material requiring a placard under the provisions of paragraph (d)(2)(ii)(a), the aggregate gross weight of which totals 1,000 pounds or more, shall be marked or placarded "Dangerous" as well as "Explosive A" or "Explosive B" as appropriate. If explosives Class A and explosives Class B are loaded on the same vehicle, the "Explosives B" marking need not be displayed.
Only extinguishers listed or approved by a nationally recognized testing laboratory shall be deemed suitable for use on explosives-carrying vehicles. Refer to § 1910.155(c)(3)(iv)(A) for definition of listed, and § 1910.7 for nationally recognized testing laboratory.
Operation of transportation vehicles.
For the purpose of this subdivision, a motor vehicle shall be deemed "attended" only when the driver or other attendant is physically on or in the vehicle, or has the vehicle within his field of vision and can reach it quickly and without any kind of interference "attended" also means that the driver or attendant is awake, alert, and not engaged in other duties or activities which may divert his attention from the vehicle, except for necessary communication with public officers, or representatives of the carrier shipper, or consignee, or except for necessary absence from the vehicle to obtain food or to provide for his physical comfort.
Use of explosives and blasting agents -
Storage at use sites.
Loading of explosives in blast holes.
Initiation of explosive charges.
Warning required. Before a blast is fired, the employer shall require that a loud warning signal be given by the person in charge, who has made certain that all surplus explosives are in a safe place, all persons and vehicles are at a safe distance or under sufficient cover, and that an adequate warning has been given.
Explosives at piers, railway stations, and cars or vessels not otherwise specified in this standard -
Railway cars. Except in an emergency and with permission of the local authority, no person shall have or keep explosives in a railway car unless said car and contents and methods of loading are in accordance with the U.S. Department of Transportation Regulations for the Transportation of Explosives, 49 CFR chapter I.
Packing and marking. No person shall deliver any explosive to any carrier unless such explosive conforms in all respects, including marking and packing, to the U.S. Department of Transportation Regulations for the Transportation of Explosives.
Marking cars. Every railway car containing explosives which has reached its designation, or is stopped in transit so as no longer to be in interstate commerce, shall have attached to both sides and ends of the car, cards with the words “Explosives - Handle Carefully - Keep Fire Away” in red letters at least 1½ inches high on a white background.
Storage. Any explosives at a railway facility, truck terminal, pier, wharf harbor facility, or airport terminal whether for delivery to a consignee, or forwarded to some other destination shall be kept in a safe place, isolated as far as practicable and in such manner that they can be easily and quickly removed.
Hours of transfer. Explosives shall not be delivered to or received from any railway station, truck terminal, pier, wharf, harbor facility, or airport terminal between the hours of sunset and sunrise.
Blasting agents -
General. Unless otherwise set forth in this paragraph, blasting agents, excluding water gels, shall be transported, stored, and used in the same manner as explosives. Water gels are covered in paragraph (h) of this section.
Fixed location mixing.
No hydrocarbon liquid fuel with flashpoint lower than that of No. 2 diesel fuel oil 125 °F. minimum shall be used.
Bulk delivery and mixing vehicles.
The hauling of either blasting caps or other explosives but not both, shall be permitted on bulk trucks provided that a special wood or nonferrous-lined container is installed for the explosives. Such blasting caps or other explosives shall be in DOT-specified shipping containers: see 49 CFR chapter I.
Bulk storage bins.
Bins containing blasting agent shall be located, with respect to inhabited buildings, passenger railroads, and public highways, in accordance with Table-21 and separation from other blasting agent storage and explosives storage shall be in conformity with Table H-22.
Bins containing ammonium nitrate shall be separated from blasting agent storage and explosives storage in conformity with Table H-22.
Table H-22 - Table of Recommended Separation Distances of Ammonium Nitrate and Blasting Agents From Explosives or Blasting Agents1-6
|Donor weight||Minimum separation distance of receptor when barricaded2 (ft.)||Minimum thickness of artificial barricades5 (in.)|
|Pounds over||Pounds not over||Ammonium nitrate3||Blasting agent4|
1 These distances apply to the separation of stores only. Table H-21 shall be used in determining separation distances from inhabited buildings, passenger railways, and public highways.
2 When the ammonium nitrate and/or blasting agent is not barricaded, the distances shown in the table shall be multiplied by six. These distances allow for the possibility of high velocity metal fragments from mixers, hoppers, truck bodies, sheet metal structures, metal container, and the like which may enclose the “donor”. Where storage is in bullet-resistant magazines recommended for explosives or where the storage is protected by a bullet-resistant wall, distances, and barricade thicknesses in excess of those prescribed in Table H-21 are not required.
3 The distances in the table apply to ammonium nitrate that passes the insensitivity test prescribed in the definition of ammonium nitrate fertilizer promulgated by the National Plant Food Institute*; and ammonium nitrate failing to pass said test shall be stored at separation distances determined by competent persons. (*Definition and Test Procedures for Ammonium Nitrate Fertilizer, National Plant Food Institute, November 1964.)
4 These distances apply to nitro-carbo-nitrates and blasting agents which pass the insensitivity test prescribed in the U.S. Department of Transportation (DOT) regulations.
5 Earth, or sand dikes, or enclosures filled with the prescribed minimum thickness of earth or sand are acceptable artificial barricades. Natural barricades, such as hills or timber of sufficient density that the surrounding exposures which require protection cannot be seen from the “donor” when the trees are bare of leaves, are also acceptable.
6 When the ammonium nitrate must be counted in determining the distances to be maintained from inhabited buildings, passenger railways and public highways, it may be counted at one-half its actual weight because its blast effect is lower.
Guide to use of table of recommended separation distances of ammonium nitrate and blasting agents from explosives or blasting agents.
Consider separately each donor mass in combination with each acceptor mass. If the masses are closer than table allowance (distances measured between nearest edges), the combination of masses becomes a new potential donor of weight equal to the total mass. When individual masses are considered as donors, distances to potential acceptors shall be measured between edges. When combined masses within propagating distance of each other are considered as a donor, the appropriate distance to the edge of potential acceptors shall be computed as a weighted distance from the combined masses.
Calculation of weighted distance from combined masses:
Let M2, M3 . . . Mn be donor masses to be combined.
M1 is a potential acceptor mass.
D12 is distance from M1 to M2 (edge to edge).
D13 is distance from M1 to M3 (edge to edge), etc.
To find weighted distance [D1(2,3 . . . n)] from combined masses to M1, add the products of the individual masses and distances and divide the total by the sum of the masses thus:
D1(2,3 . . . n)=M2 X D12 + M3 X D12 . . . + Mn X D12M2 + M3 . . . + Mn
Propagation is possible if either an individual donor mass is less than the tabulated distance from an acceptor or a combined mass is less than the weighted distance from an acceptor.
In determining the distances separating highways, railroads, and inhabited buildings from potential explosions (as prescribed in Table H-21), the sum of all masses which may propagate (i.e., lie at distances less than prescribed in the Table) from either individual or combined donor masses are included. However, when the ammonium nitrate must be included, only 50 percent of its weight shall be used because of its reduced blast effects. In applying Table H-21 to distances from highways, railroads, and inhabited buildings, distances are measured from the nearest edge of potentially explodable material as prescribed in Table H-21, Note 5.
Storage of blasting agents and supplies.
Transportation of packaged blasting agents.
Use of blasting agents. Persons using blasting agents shall comply with all of the applicable provisions of paragraph (e) of this section.
Water gel (Slurry) explosives and blasting agents -
General provisions. Unless otherwise set forth in this paragraph, water gels shall be transported, stored and used in the same manner as explosives or blasting agents in accordance with the classification of the product.
Types and classifications.
Water gels containing a substance in itself classified as an explosive shall be classified as an explosive and manufactured, transported, stored, and used as specified for "explosives" in this section, except as noted in subdivision (iv) of this subparagraph.
Water gels containing no substance in itself classified as an explosive and which are cap-sensitive as defined in paragraph (a) of this section under Blasting Agent shall be classified as an explosive and manufactured, transported, stored and used as specified for "explosives" in this section.
Water gels containing no substance in itself classified as an explosive and which are not cap-sensitive as defined in paragraph (a) of this section under Blasting Agent shall be classified as blasting agents and manufactured, transported, stored, and used as specified for "blasting agents" in this section.
Fixed location mixing.
Buildings used for the mixing of water gels shall conform to the requirements of this subdivision.
Buildings shall be of noncombustible construction or sheet metal on wood studs.
The mixing, loading, and ingredient transfer areas where residues or spilled materials may accumulate shall be cleaned periodically. A cleaning and collection system for dangerous residues shall be provided. ,
Bulk delivery and mixing vehicles.
The design of processing equipment and general requirements shall conform to subparagraphs (3) (iii) and (iv) of this paragraph.
The hauling of either blasting caps or other explosives, but not both, shall be permitted on bulk trucks provided that a special wood or nonferrous-lined container is installed for the explosives. Such blasting caps or other explosives shall be in DOT-specified shipping containers; see 49 CFR chapter I.
Storage of ammonium nitrate -
Scope and definitions.
The storage of ammonium nitrate and ammonium nitrate mixtures that are more sensitive than allowed by the "Definition of Test Procedures for Ammonium Nitrate Fertilizer" is prohibited.
The standards for ammonium nitrate (nitrous oxide grade) are those found in the “Specifications, Properties, and Recommendations for Packaging, Transportation, Storage, and Use of Ammonium Nitrate”, available from the Compressed Gas Association, Inc., which is incorporated by reference as specified in § 1910.6.
The wall on the exposed side of a storage building within 50 feet of a combustible building, forest, piles of combustible materials and similar exposure hazards shall be of fire-resistive construction. In lieu of the fire-resistive wall, other suitable means of exposure protection such as a free standing wall may be used. The roof coverings shall be Class C or better, as defined in the Manual on Roof Coverings, NFPA 203M-1970, which is incorporated by reference as specified in § 1910.6.
Storage of ammonium nitrate in bags, drums, or other containers.
Bags and containers used for ammonium nitrate must comply with specifications and standards required for use in interstate commerce (see 49 CFR chapter I).
Containers of ammonium nitrate shall not be accepted for storage when the temperature of the ammonium nitrate exceeds 130 °F.
Storage of bulk ammonium nitrate.
The ammonium nitrate storage bins or piles shall be clearly identified by signs reading "Ammonium Nitrate" with letters at least 2 inches high.
Ammonium nitrate shall not be accepted for storage when the temperature of the product exceeds 130 °F.
Flammable liquids such as gasoline, kerosene, solvents, and light fuel oils shall not be stored on the premises except when such storage conforms to § 1910.106, and when walls and sills or curbs are provided in accordance with paragraphs (i)(5)(i) (a) or (b) of this section.
LP-Gas shall not be stored on the premises except when such storage conforms to § 1910.110.
In areas where lightning storms are prevalent, lightning protection shall be provided. (See the Lightning Protection Code, NFPA 78-1968, which is incorporated by reference as specified in § 1910.6.)
Not more than 2,500 tons (2270 tonnes) of bagged ammonium nitrate shall be stored in a building or structure not equipped with an automatic sprinkler system. Sprinkler systems shall be of the approved type and installed in accordance with § 1910.159.
Suitable fire control devices such as small hose or portable fire extinguishers shall be provided throughout the warehouse and in the loading and unloading areas. Suitable fire control devices shall comply with the requirements of §§ 1910.157 and 1910.158.
Small arms ammunition, small arms primers, and small arms propellants -
Scope. This paragraph does not apply to in-process storage and intraplant transportation during manufacture of small arms ammunition, small arms primers, and smokeless propellants.
Small arms ammunition.
Small arms ammunition primers.
This section applies to the manufacture, keeping, having, storage, sale, transportation, and use of explosives, blasting agents, and pyrotechnics. The section does not apply to the sale and use (public display) of pyrotechnics, commonly known as fireworks, nor the use of explosives in the form prescribed by the official U.S. Pharmacopeia.
The manufacture of explosives as defined in paragraph (a)(3) of this section shall also meet the requirements contained in § 1910.119.
The manufacture of pyrotechnics as defined in paragraph (a)(10) of this section shall also meet the requirements contained in § 1910.119.
[39 FR 23502, June 27, 1974, as amended at 43 FR 49747, Oct. 24, 1978; 45 FR 60704, Sept. 12, 1980; 53 FR 12122, Apr. 12, 1988; 57 FR 6403, Feb. 24, 1992; 58 FR 16496, March 29, 1993; 58 FR 35309, June 30, 1993; 61 FR 9227, March 7, 1996; 63 FR 33450, June 18, 1998]