Subpart U - Blasting and Use of Explosives

Scope: This standard provides the general provisions for blasting and the use of explosives.

Special Requirements: Authorized person, qualified person, notified, record, inventory, warning signals, signs, competent person, description (alternatives), writing, certified, safe control measures, references other standards

1926.900(a) - The employer shall permit only authorized and qualified persons to handle and use explosives.

1926.900(d) - All explosives shall be accounted for at all times. Explosives not being used shall be kept in a locked magazine, unavailable to persons not authorized to handle them. The employer shall maintain an inventory and use record of all explosives. Appropriate authorities shall be notified of any loss, theft, or unauthorized entry into a magazine.

1926.900(i) - Employees authorized to prepare explosive charges or conduct blasting operations shall use every reasonable precaution including, but not limited to, visual and audible warning signals, flags, or barricades, to ensure employee safety.

1926.900(k)(3)(i) - The prominent display of adequate signs, warning against the use of mobile radio transmitters, on all roads within 1,000 feet of blasting operations. Whenever adherence to the 1,000-foot distance would create an operational handicap, a competent person shall be consulted to evaluate the particular situation, and alternative provisions may be made which are adequately designed to prevent any premature firing of electric blasting caps. A description of any such alternatives shall be reduced to writing and shall be certified as meeting the purposes of this subdivision by the competent person consulted. The description shall be maintained at the construction site during the duration of the work, and shall be available for inspection by representatives of the Secretary of Labor.

1926.900(k)(3)(ii) - Specimens of signs which would meet the requirements of paragraph (k)(3) of this section are the following: [Reference paragraph (k)(3)(ii)].

1926.900(k)(5) - Compliance with the recommendations of The Institute of the Makers of Explosives with regard to blasting in the vicinity of radio transmitters as stipulated in Radio Frequency Energy-A Potential Hazard in the Use of Electric Blasting Caps, IME Publication No. 20, March 1971.

1926.900(n) - Delivery and issue of explosives shall only be made by and to authorized persons and into authorized magazines or approved temporary storage or handling areas.

1926.900(o) - Blasting operations in the proximity of overhead power lines, communication lines, utility services, or other services and structures shall not be carried on until the operators and/or owners have been notified and measures for safe control have been taken.

1926.900(q) - All loading and firing shall be directed and supervised by competent persons thoroughly experienced in this field.

1926.900(r) - All blasts shall be fired electrically with an electric blasting machine or properly designed electric power source, except as provided in 1926.906(a) - Initiation of explosive charges - electric blasting, and (r).

Scope: This standard provides the requirements for blaster qualifications.

Special Requirements: Understand written orders, physical condition, qualified, training, evidence of competency, competent, knowledgeable, knowledge of State and local laws and regulations

Blaster - The person or persons authorized to use explosives for blasting purposes and meeting the qualifications contained in 1926.901 - blaster qualifications.

1926.901(a) - A blaster shall be able to understand and give written and oral orders.

1926.901(b) - A blaster shall be in good physical condition and not be addicted to narcotics, intoxicants, or similar types of drugs.

1926.901(c) - A blaster shall be qualified, by reason of training, knowledge, or experience, in the field of transporting, storing, handling, and use of explosives, and have a working knowledge of State and local laws and regulations which pertain to explosives.

1926.901(d) - Blasters shall be required to furnish satisfactory evidence of competency in handling explosives and performing in a safe manner the type of blasting that will be required.

1926.901(e) - The blaster shall be knowledgeable and competent in the use of each type of blasting method used.

Scope: This standard provides the requirements for surface transportation of explosives.

Special Requirements: Licensed driver, physically fit, regulations, manufacturer's container, markings, placarding, explosives (word), Underwriters Laboratory-approved extinguisher, trained, reference other standards

1926.902(a) - Transportation of explosives shall meet the provisions of Department of Transportation regulations contained in 46 CFR parts 146-149, Water Carriers; 49 CFR parts 171-179, Highways and Railways; 49 CFR part 195, Pipelines; and 49 CFR parts 390-397, Motor Carriers.

1926.902(b) - Motor vehicles or conveyances transporting explosives shall only be driven by, and be in the charge of, a licensed driver who is physically fit. He shall be familiar with the local, State, and Federal regulation governing the transportation of explosives.

1926.902(f) - When explosives are transported by a vehicle with an open body, a Class II magazine or original manufacturer's container shall be securely mounted on the bed to contain the cargo.

1926.902(h) - Every motor vehicle or conveyance used for transporting explosives shall be marked or placarded on both sides, the front, and the rear with the word "Explosives" in red letters, not less than 4 inches in height, on white background. In addition to such marking or placarding, the motor vehicle or conveyance may display, in such a manner that it will be readily visible from all directions, a red flag 18 inches by 30 inches, with the word "Explosives" painted, stamped, or sewed thereon, in white letters, at least 6 inches in height.

1926.902(i) - Each vehicle used for transportation of explosives shall be equipped with a fully charged fire extinguisher, in good condition. An Underwriters Laboratory-approved extinguisher of not less than 10-ABC rating will meet the minimum requirement. The driver shall be trained in the use of the extinguisher on his vehicle.

Scope: This standard provides the requirements for underground transportation of explosives.

Special Requirements: Certification record, hoist operator notified, inspection, signature, weekly checks, sign, word (explosives)

1926.903(d) - The hoist operator shall be notified before explosives or blasting agents are transported in a shaft conveyance.

1926.903(e) - Trucks used for the transportation of explosives underground shall have the electrical system checked weekly to detect any failures which may constitute an electrical hazard. A certification record which includes the date of the inspection; the signature of the person who performed the inspection; and a serial number, or other identifier, of the truck inspected shall be prepared and the most recent certification record shall be maintained on file.

1926.903(m) - The powder car or conveyance especially built for the purpose of transporting explosives or blasting agents shall bear a reflectorized sign on each side with the word "Explosives" in letters, not less than 4 inches in height; upon a background of sharply contrasting color.

Scope: This standard provides the requirements for the storage of explosives and blasting agents.

Special Requirements: Reference other standards

1926.904(a) - Explosives and related materials shall be stored in approved facilities required under the applicable provisions of the Bureau of Alcohol, Tobacco and Firearms regulations contained in 27 CFR part 55, Commerce in Explosives.

Scope: This standard provides the requirements for the loading of explosives or blasting agents.

Special Requirements: Procedures, authorized magazine, locked out, blaster, warning signs, records, inventory, Fume Class, references other standards

1926.905(a) - Procedures that permit safe and efficient loading shall be established before loading is started.

1926.905(d) - No holes shall be loaded except those to be fired in the next round of blasting. After loading, all remaining explosives and detonators shall be immediately returned to an authorized magazine.

1926.905(j) - Powerlines and portable electric cables for equipment being used shall be kept a safe distance from explosives or blasting agents being loaded into drill holes. Cables in the proximity of the blast area shall be deenergized and locked out by the blaster.

1926.905(n) - No explosives other than those in Fume Class 1, as set forth by the Institute of Makers of Explosives, shall be used; however, explosives complying with the requirements of Fume Class 2 and Fume Class 3 may be used if adequate ventilation has been provided.

1926.905(p) - Warning signs, indicating a blast area, shall be maintained at all approaches to the blast area. The warning sign lettering shall not be less than 4 inches in height on a contrasting background.

1926.905(t) - The blaster shall keep an accurate, up-to-date record of explosives, blasting agents, and blasting supplies used in a blast and shall keep an accurate running inventory of all explosives and blasting agents stored on the operation.

Scope: This standard provides the requirements for the initiation of explosive charges - electric blasting.

Special Requirements: Survey, manufacturer's recommendations, approved contractor, blaster. tested, rated capacity

1926.906(b) - Before adopting any system of electrical firing, the blaster shall conduct a thorough survey for extraneous currents, and all dangerous currents shall be eliminated before any holes are loaded.

1926.906(d) - Electric blasting shall be carried out by using blasting circuits or power circuits in accordance with the electric blasting cap manufacturer's recommendations, or an approved contractor or his designated representative. 

1926.906(e) - When firing a circuit of electric blasting caps, care must be exercised to ensure that an adequate quantity of delivered current is available, in accordance with the manufacturer's recommendations.

1926.906(l) - When firing from a power circuit, the firing switch shall be locked in the open or "Off" position at all times, except when firing. It shall be so designed that the firing lines to the cap circuit are automatically short-circuited when the switch is in the "Off" position. Keys to this switch shall be entrusted only to the blaster.

1926.906(m) - Blasting machines shall be in good condition and the efficiency of the machine shall be tested periodically to make certain that it can deliver power at its rated capacity.

1926.906(n) - When firing with blasting machines, the connections shall be made as recommended by the manufacturer of the electric blasting caps used.

1926.906(o) - The number of electric blasting caps connected to a blasting machine shall not be in excess of its rated capacity. Furthermore, in primary blasting, a series circuit shall contain no more caps than the limits recommended by the manufacturer of the electric blasting caps in use.

1926.906(p) - The blaster shall be in charge of the blasting machines, and no other person shall connect the leading wires to the machine.

1926.906(q) - Blasters, when testing circuits to charged holes, shall use only blasting galvanometers or other instruments that are specifically designed for this purpose.

Scope: This standard provides requirements for the use of the safety fuse.

Special Requirements: Approved design

1926.907(d) - Only a cap crimper of approved design shall be used for attaching blasting caps to safety fuse. Crimpers shall be kept in good repair and accessible for use.

Scope: This standard provides the requirements for the use of the detonating cord.

Special Requirements: Approved methods, recommended methods, inspected, manufacturer recommendations.

1926.908(e) - Detonating cord connections shall be competent and positive in accordance with approved and recommended methods. Knot-type or other cord-to-cord connections shall be made only with detonating cord in which the explosive core is dry.

1926.908(g) - All detonating cord connections shall be inspected before firing the blast.

1926.908(h) - When detonating cord millisecond-delay connectors or short-interval-delay electric blasting caps are used with detonating cord, the practice shall conform strictly to the manufacturer's recommendations.

Scope: This standard provides the requirements for firing the blast.

Special Requirements: Signs, signals (code), blaster, flagman, duty, danger zone, posted, warning

1926.909(a) - A code of blasting signals equivalent to Table U-1, shall be posted on one or more conspicuous places at the operation, and all employees shall be required to familiarize themselves with the code and conform to it. Danger signs shall be placed at suitable locations.

1926.909(b) - Before a blast is fired, a loud warning signal shall be given by the blaster in charge, who has made certain that all surplus explosives are in a safe place and all employees, vehicles, and equipment are at a safe distance, or under sufficient cover.

1926.909(c) - Flagmen shall be safely stationed on highways which pass through the danger zone so as to stop traffic during blasting operations.

1926.909(d) - It shall be the duty of the blaster to fix the time of blasting.

1926.909(e) - Before firing an underground blast, warning shall be given, and all possible entries into the blasting area, and any entrances to any working place where a drift, raise, or other opening is about to hole through, shall be carefully guarded. The blaster shall make sure that all employees are out of the blast area before firing a blast.

Scope: This standard provides the requirements for inspecting after blasting.

Special Requirements: Inspection, blaster

1926.910(b) - Sufficient time shall be allowed, not less than 15 minutes in tunnels, for the smoke and fumes to leave the blasted area before returning to the shot. An inspection of the area and the surrounding rubble shall be made by the blaster to determine if all charges have been exploded before employees are allowed to return to the operation, and in tunnels, after the muck pile has been wetted down.

Scope: This standard provides the requirements pertaining to misfires.

Special Requirements: Danger zone, blaster, person in charge, authorized representative, approved work

1926.911(a) - If a misfire is found, the blaster shall provide proper safeguards for excluding all employees from the danger zone.

1926.911(b) - No other work shall be done except that necessary to remove the hazard of the misfire and only those employees necessary to do the work shall remain in the danger zone.

1926.911(d) - If there are any misfires while using cap and fuse, all employees shall remain away from the charge for at least 1 hour. Misfires shall be handled under the direction of the person in charge of the blasting. All wires shall be carefully traced and a search made for unexploded charges.

1926.911(e) - No drilling, digging, or picking shall be permitted until all missed holes have been detonated or the authorized representative has approved that work can proceed.

Scope: This standard provides the requirements pertaining to underwater blasting.

Special Requirements: Blaster, approval, notified (nearby craft), signals, blasting flags, agreed upon arrangements, references other standards

1926.912(a) - A blaster shall conduct all blasting operations, and no shot shall be fired without his approval.

1926.912(d) - No blast shall be fired while any vessel under way is closer than 1,500 feet to the blasting area. Those on board vessels or craft moored or anchored within 1,500 feet shall be notified before a blast is fired.

1926.912(e) - No blast shall be fired while any swimming or diving operations are in progress in the vicinity of the blasting area. If such operations are in progress, signals and arrangements shall be agreed upon to assure that no blast shall be fired while any person is in the water.

1926.912(f) - Blasting flags shall be displayed.

1926.912(h) - When more than one charge is placed under water, a float device shall be attached to an element of each charge in such manner that it will be released by the firing. Misfires shall be handled in accordance with the requirements of 1926.911 - misfires.

Scope: This standard provides the requirements for blasting in excavation work under compressed air.

Special Requirements: Fume Class 1, blasting zone, powderman, blaster, lock tender

1926.913(a) - Detonators and explosives shall not be stored or kept in tunnels, shafts, or caissons. Detonators and explosives for each round shall be taken directly from the magazines to the blasting zone and immediately loaded. Detonators and explosives left over after loading a round shall be removed from the working chamber before the connecting wires are connected up.

1926.913(b) - When detonators or explosives are brought into an air lock, no employee except the powderman, blaster, lock tender and the employees necessary for carrying, shall be permitted to enter the air lock. No other material, supplies, or equipment shall be locked through with the explosives.

1926.913(d) - The blaster or powderman shall be responsible for the receipt, unloading, storage, and on-site transportation of explosives and detonators.

1926.913(f) - The explosives suitable for use in wet holes shall be water-resistant and shall be Fume Class 1.