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(m) Drivers of vehicles containing explosive materials shall not be permitted to leave the cab without first stopping the motor and setting the parking brake. Precautions shall be taken to prevent the movement of such vehicles.
(n) Except under emergency conditions, no vehicle transporting explosive materials shall be parked unattended before reaching its destination. No vehicle transporting explosive materials shall be parked on any public street adjacent to or in proximity to any place where people work or congregate. NOTE:For the purpose of this subsection, 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 their field of vision and can reach it quickly and without interference. "Attended" also means that the driver or attendant is awake, alert, and not engaged in other duties or activities which may divert their attention from the vehicle. However, an explosive-laden vehicle may be left unattended if parked within a securely fenced or walled area with all gates or entrances locked where parking of such vehicle is permitted or at a magazine site established solely for the purpose of storing explosives.
(o) Incompatible materials, such as flammable liquids, flames or spark producing materials or combustibles materials, shall not be carried in the vehicle's cargo space with explosive materials.
(p) No person shall be permitted to smoke, carry matches or any other flame-producing device, or carry any unauthorized firearms or loaded cartridges while in or near a motor vehicle transporting explosive materials, or drive, load or unload such vehicle in a careless or reckless manner.
(q) Delivery of explosive materials shall be made only to authorized persons and into authorized magazines or authorized temporary storage or handling areas.
(r) The transfer of explosive materials from storage places shall be so arranged that no undue delay will occur between the time the explosive materials leave the storage place and the time they are used.
(s) Explosive materials shall not be transferred from one vehicle to another within the confines of any jurisdiction (city, county, or other area) without informing the fire and police and/or sheriff's departments thereof. In the event of breakdown or collision, the appropriate local emergency services agencies shall be promptly notified. The explosive materials shall be transferred from the disabled vehicle to another only when qualified supervision is provided. NOTE:Federal DOT and local regulations shall also apply when applicable.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5263. Surface Transportation.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3 Labor Code.
s 5264. Transportation of Explosive Materials -Underground -General.
(a) Explosive materials shall not be left on the station level near the shaft collar, mine, or tunnel entrance, but shall be taken to the place of use or storage without delay.
(b) Detonators, capped fuses, and other explosive materials transported in any car, vehicle, or shaft conveyance shall be enclosed in substantially constructed containers equipped with tight-fitting covers. Such containers, including the covers, shall be made of wood, metal, fiber, or other equivalent material and shall be lined with nonconductive material. Note:Except for primers, the original cases or DOT shipping containers in which the explosive materials were packaged will be accepted as being in compliance with this subsection.
(c) Except as provided in Section 5264(c)(1), detonators, primers, or capped fuses, shall not be transported in the same container or compartment with other explosive materials.
(1) When carried in the same vehicle, detonators and capped fuses shall be in a separate compartment from the other explosive materials with at least 25 inches of air space between the compartments.
(d) Except when being transported manually, primers shall be transported in a closed container constructed as described in subsection (b) of this section, and arranged so that each primer is separated from the others by a partition of nonmetallic material. No explosive materials, other than that which is contained in the primer, shall be transported in the same container with the primers.
(e) Explosive materials shall not be transported with rock, ore, or other materials or equipment other than those used in blasting.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5265. Transportation of Explosive Materials -Underground -Hoisting or Lowering.
(a) No employees except those specifically required and designated by the person in charge of the mine or tunnel, shall be permitted to ride in any shaft conveyance at the same time as explosive materials are being transported in such shaft.
(b) The hoist engineer shall be notified before explosive materials are transported in the shaft conveyance.
(c) Explosive materials shall be in a suitable conveyance while being hoisted from or lowered to any place underground.
(d) Hoisting of ore, muck or other materials in adjacent shaft compartments shall be stopped while explosive materials are being handled.
(e) Detonators and primers shall not be transported at the same time with other explosive materials in any shaft conveyance unless in a powder car.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5266. Rail Transportation of Explosive Materials -Underground.
(a) Only the train crew and powder crew shall be permitted to ride on a train transporting explosive materials.
(b) Explosive materials in quantities of 110 pounds or more when transported on a train, shall be in special powder cars. Such cars shall be constructed of metal and have closed compartments for the explosive materials. The compartments shall be lined with nonconductive material.
(c) Explosive materials shall not be transported on or in any locomotive. When transporting explosive materials by train, at least one empty car shall be kept between the locomotive and the car which contains explosive materials.
(d) Each side of the special powder car shall bear a sign with the word "EXPLOSIVES" in letters not less than 4 inches high with a 5/8-inch stroke on a background of sharply contrasting color.
(e) Powder cars that are carrying explosive materials shall be pulled, not pushed, except when switching or traveling at the dead end of a line.
(f) The primers shall be placed in a primer compartment of the powder car in a suitable box with divisions for each separate delay. If capped fuses are used, they must be in a suitable container in the primer compartment. The primer and powder compartments shall be separated by at least 25 inches of air space.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5267. Transportation of Explosive Materials -Underground - Special Trackless Vehicles.
(a) Trackless vehicles used for the transportation of explosive materials shall be especially equipped for that purpose and shall be carefully maintained in compliance with the provisions of section 5262.
(b) Truck-type vehicles used for the transportation of explosive materials shall be especially equipped with closed compartments for the explosive materials. The compartments shall be lined with nonconductive materials.
(c) Each side, front, and rear of every truck-type vehicle, when transporting explosive materials, shall bear a sign with the word "EXPLOSIVES" in letters not less than 4 inches high with a 5/8-inch stroke on a background of sharply contrasting color.
(d) Truck-type vehicles when transporting explosive materials underground, shall be equipped with a flashing red light visible from the front and rear.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5268. Transportation of Explosive Materials -Manual.
(a) Explosive materials that are transported manually from one area to another shall be placed in suitable bags or other containers for such transportation.
(b) Detonators and primers shall be transported separately from other explosive materials.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5269. Transportation of Explosive Materials -Air and Water.
Aircraft and water transportation of explosive materials shall comply with standards of Federal Government or equivalent to such standards.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5270. Explosive Materials at Railway and Truck Terminals.
(a) Every railway car and truck containing explosive materials which has reached its destination, or is stopped in transit so as no longer to be in interstate commerce, shall remain placarded in accordance with the regulations of the U.S. Department of Transportation.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5276. General.
(a) There shall be no smoking, open flames or other sources of ignition within 50 feet of any area where explosive materials are being handled, except devices necessary to ignite the fuses of set charges. NOTE:Internal combustion engines equipped with spark arresters which are functioning as designed are not considered sources of ignition.
(b) Tools used for opening containers of explosive materials shall be constructed of non-sparking material, except that metal slitters may be used for opening fiberboard containers provided that the metal slitter does not come into contact with any metallic fasteners which may be in or part of the case. Only a wooden wedge and a fiber, rubber or wooden mallet shall be used for opening or closing wood containers of explosive materials.
(c) Empty boxes, paper and fiber packing materials which have previously contained high explosives shall not be used again for any other purpose. They shall be destroyed by burning at an isolated location out of doors, and no person shall be nearer than 100 feet after the burning has started.
Exception: Containers designed and maintained for reuse.
(d) Explosive materials shall not be placed within 25 feet of an electrical circuit except during transportation.
(e) Explosive materials left over after loading operations are completed, shall be promptly returned to their proper magazines.
(f) When blasting in a location where flying rock or material may damage other property or endanger employees, all loaded holes shall be covered with a blasting mat that has been anchored.
(g) No person under the age of 21 years shall be permitted in any explosive magazine or be permitted to use, handle, or transport explosives.
Exception: Persons 18 years or older and under the direct personal supervision of a licensed blaster.
(h) Spilled explosive materials shall be cleaned up promptly.
(i) Explosive materials shall not be subjected to excessive heat, friction or force.
(j) Explosive materials shall be used only at temperatures recommended by the manufacturer.
(k) Defective blasting equipment shall not be used.
(l) No fire shall be fought where the explosive materials are in imminent danger of contact with the fire. All employees shall be removed to a safe area and the fire area guarded against intruders.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5277. Tamping Poles or Devices.
(a) Tamping poles or devices shall be made of wood or plastic materials manufactured for tamping explosives. NOTE:There are many kinds of "plastics," most of which cannot be used safely for tamping explosives. Some plastics are too soft to withstand physical abuse, some are too hard, others are flammable or will absorb nitroglycerin or generate hazardous accumulations of static electricity.
(b) The end of the tamping pole shall be kept squared and shall be of such size that the pole will not bypass the cartridges in the hole.
(c) Wooden tamping poles shall have no metal parts, other than non-ferrous metal ferrules, for extending the length of the pole.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5278. Loading of Explosive Materials -General.
(a) Loading shall not commence until all drilling is completed and drill holes are cleaned or blown out, unless this procedure is impracticable under conditions encountered. When conditions justify simultaneous loading and drilling in the same area, such operations shall be separated as widely as practicable and in no case shall a drilling operation be closer than 50 feet to a hole being loaded. All drill holes shall be sufficiently large to freely admit the insertion of the explosive materials.
(b) At least 5 foot candles illumination shall be provided to safely perform loading operations. Only approved lights shall be used within 50 feet of the loading area.
(c) No vehicle traffic shall be permitted over loaded holes.
(d) Loading operations shall be carried on with the smallest practical number of persons and explosive materials loading equipment present and no one but the loading crew, inspection personnel, and authorized supervisory personnel shall be allowed within 50 feet of the loading area.
(1) At locations where 50 foot minimum distance cannot be maintained, an alternative plan shall be submitted to the Division for approval 30 days prior to anticipated start of work. The Division shall give written notice of receipt to the applicant within 7 days. Notice of approval/disapproval, shall be given within 15 days of receipt of the application. The Division may shorten the 30- day notification requirement where construction has commenced and unexpected site and/or emergency conditions requiring blasting occur.
(2) The Division shall approve the alternative plan if the following elements are satisfied:
(A) All blasting operations will be conducted using low sensitivity explosive materials.
(B) All blasting operations will be conducted using initiation systems which cannot be affected by stray current or radio frequency energy.
(C) A lightning and electric storm-detection system and written plan of action is provided to the Division. The plan shall include provisions for a detection system capable of warning the loading crew when a storm is 100 miles away. When a storm is detected 50 miles from the loading operation, the storm's movement is to be monitored. When a storm is detected at 25 miles from the loading operation, loading operations will be discontinued and all persons in the blast area withdrawn to a safe location.
(D) K-rails, barriers, traffic control systems or natural terrain shall be used to prevent entry by vehicular traffic into the loading site.
(e) The amount of explosive materials delivered into a loading area shall not exceed the amount estimated by the licensed blaster as necessary for the blasting. No holes shall be loaded except those to be fired in the next round of blasting.
(f) Detonators shall not be less strength than No. 8.
(g) The detonator, if used, shall be properly encased in explosives when inserted into the drill hole.
(h) Tamping shall be by pressured or light blows only, and never by excessive ramming. The primer shall not be tamped.
(i) All blast holes in open work shall be stemmed to a point that will sufficiently confine the charge.
(j) Stacks of explosive materials shall be spaced and distributed in the loading area to prevent propagation of an explosion between any two piles or loaded holes in the event of a premature explosion in any portion of the blast area.
(k) Springing holes:
(1) Boreholes shall not be sprung within 100 feet of any hole containing explosive materials for primary blasting.
(2) A hole that has been sprung shall not be loaded until sufficient time has elapsed for the hole to cool. Artificial means may be used to cool the hole.
(l) Except for avalanche blasting, drop fuses or any other method that calls for ignition of the fuse prior to placement of the charge in its final position shall not be used.
(m) Drill holes or any part of such holes which have been charged with explosive materials shall not be deepened.
(n) Drilling shall not be started until all remaining butts of old holes are examined for unexploded charges and if any are found, they shall be detonated or properly disposed of before other work proceeds. (See Section 5293).
(o) Except as provided in Section 5278(w), holes to be blasted shall be charged as near to blasting time as practical and such holes shall be blasted as soon as possible after charging has been completed.
(1) No explosive materials shall be left unattended at the blast site.
(2) Loaded holes shall not be left unattended except as permitted in Section 5278(w).
(p) Explosive materials shall be kept separated from detonators until charging is started.
(q) Capped primers shall be made up at the time of charging and as close to the blasting site as conditions allow.
(r) Only wooden or other nonsparking implements shall be used to punch holes in an explosive cartridge.
(s) Areas in which charged holes are awaiting firing shall be guarded or barricaded and posted or flagged against unauthorized entry.
(t) The double-trunkline or loop system shall be used in detonating-cord blasting.
(u) Trunklines, in multiple-row blasts, shall make 1 or more complete loops, with crossties between loops at intervals of not over 200 feet.
(v) All detonating cord knots shall be tight and all connections shall be kept at right angles to the trunklines.
(w) Loaded holes intended for geophysical operations:
(1) Shall be attended; or
(2) May be left attended, but only where the loaded explosives, if detonated, it will not cause injuries and where the loaded explosives are:
(A) Anchored, tamped or stemmed so that the charge cannot be removed; or
(B) Left so that the detonator leads are inaccessible to or concealed from unauthorized persons.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5279. Loading and Blasting Near or Under Power Lines.
(a) When electric initiated blasting under, or near overhead power lines, the leading wires shall be placed at right angles to such lines and shall be securely anchored to prevent the blasting circuit conductors from being thrown into the overhead lines.
(b) When blasting under, or near overhead power lines, all loaded holes shall be covered with a nonconductive blasting mat anchored to prevent the mat or other material from being blown into the overhead lines.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5280. Pneumatic Loading of Explosive Materials for Blasting.
(a) Construction of Air Loaders.
(1) Blasting agents shall not be loaded into any air loader constructed of copper, copper alloys, or zinc (including galvanized metals) unless the loader is constructed so that such incompatible materials do not come in contact with blasting agents.
(2) An explosive shall not be loaded into any air loader constructed wholly or in part of ferrous metals except that stainless steel may be used.
(3) The vessel that is pressurized on an air loader shall be designed, constructed, inspected, and stamped in compliance with the Unfired Pressure Vessel Safety Orders.
(b) Air Loader Equipment.
(1) A 20-mesh screen, an air trap or a filter shall be installed in the air supply line adjacent to the loader when a pressure vessel is being used.
(2) An air pressure reducing regulator of standard manufacture shall be installed in the air supply line and be a part of the loader assembly for a pressure-type loader.
(3) An air pressure relieving safety valve of adequate capacity shall be installed in the air supply line between the air pressure reducing regulator and the pressure vessel of the air loader. There shall be no valve between the pressure vessel and the pressure relieving device.
(4) An adequate pressure gauge shall be installed in the air supply line between the air pressure reducing regulator and the air loader pressure vessel.
(c) Air Temperature and Pressure.
(1) The temperature of the air supplied to the air loader shall not exceed 150 degrees Fahrenheit.
(2) The air pressure shall not exceed 50 pounds per square inch when explosive materials are being loaded.
(3) The air pressure relieving safety valve shall be set to open at a pressure not to exceed 55 pounds per square inch, when an explosive is being loaded.
(4) When a blasting agent is being loaded, the safety valve shall be set at not more than 110% of the safe loading pressure, but in no case to exceed 110 psi.
(d) Control of Static Electricity and Stray Currents.
(1) There shall be continuous electrical path from the discharge end of the loading tube, through the loading tube, the loading line, the air loader, and to ground. The loading tube shall be static dissipating and shall be at least 2 feet longer than the deepest hole loaded.
(2) Where metal air loaders are on non-conductive rock or earth, an auxiliary ground shall be provided by metal straps or cables of at least #8 American Wire Gauge connected to ground rods. If it is necessary, the ground rods shall be driven into water-filled holes. The total resistance from the discharge end of the loading tube to ground shall not exceed two megohms.
(3) Pneumatic loading equipment shall not be grounded to water lines, airlines, rails, or other permanent electrical grounding systems.
(4) The loading tube and loading hose, if one piece, shall be either of a distinctive design or else identified at least every 18 inches that it is static dissipating.
(e) Operations and Procedures.
(1) The air supply line shall be thoroughly blown out before it is attached to the air loader.
(2) All material poured into a pressure type air loader shall be passed through a screen having openings not larger than half an inch.
(3) Air loaders when used to blow or force stemming into loaded holes shall be thoroughly cleaned before and after such use.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5291. Firing of Explosive Materials (Blasting Operations).
(a) The licensed blaster-in-charge shall fix the time of blasting.
(b) Blasts are not to be fired without a warning signal/procedure and until definite assurance that all surplus explosive materials are in a safe place, and all persons are at a safe distance or under sufficient cover.
(c) Precautions, such as the following, shall be taken to prevent unauthorized entry into the blast area: warning signs, barricades, or flaggers when necessary.
(d) Warning signals shall be given by the use of a compressed air whistle, a horn, lights or equivalent means, such as flaggers or voice warning and shall be clearly audible at the most distant point in the blast area. Where other than flagger or other visible method or voice warning is used, the following signals are recommended:
WARNING SIGNAL
5 minutes prior to the blast A 1-minute series of long audible
signals
BLASTING SIGNAL
1 minute prior to the blast A series of short audible signals
ALL-CLEAR SIGNAL
Following inspection of the blast area A prolonged audible signal
(e) The type of warning signal or method shall be posted at one or more conspicuous locations and all employees shall be made familiar with the signals and instructed accordingly.
(f) The "ALL CLEAR" signal shall not be given until the licensed blaster has made a thorough, visual inspection of the blast area for misfires. In the event of a misfire, the requirements of Section 5293 shall be complied with before the "ALL CLEAR" signal is given.
(g) 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.
(h) Whenever blasting is being conducted in the area immediately adjacent to gas pipelines, flammable liquid gas pipelines, electric, water, fire alarm, telephone, telegraph, and steam utilities, the licensed blaster shall notify the appropriate representatives of such pipelines or utilities at least 24 hours in advance of blasting, specifying the location and intended time of such blasting. Verbal notice shall be confirmed with written notice before the blast. In an emergency this time limit may be waived.
(i) Employees shall be prohibited from entering the blast area after blasting until any toxic vapor/fumes, dust and gases have been reduced to safe limits.
(j) After blasting, the blasting crew shall wait at least 5 minutes before returning to the point of blasting.
(k) For underground blasting, no one shall enter the place where primary blasting has been done for at least 15 minutes.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5292. Secondary Blasting.
(a) There shall be no activity of any kind that would create a hazard to explosive materials that have been placed or are being placed for secondary blasting.
(b) Where shots are to be fired in such close proximity that one shot may displace another, the firing shall be done by use of detonating cord or instantaneous electric blasting caps.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5293. Misfires.
(a) After each shot the blast area shall be examined for misfires. If any are found, or suspected to exist, they shall be reported to the person in charge. Steps shall be taken to eliminate all undetonated explosive materials.
(b) In case of a detonator misfire, the shot area shall be made safe under competent supervision by one of the following means after a 30-minute wait following electric or non-electric shock tube blasting, or a 60-minute wait following fuse cap blasting:
(1) Where practical a new primer shall be inserted into the hole and the hole reblasted, or
(2) Where the hole cannot be reblasted, the stemming and explosive shall be washed out with water, or
(3) Where blasting agents are used, try to remove the detonator and cap sensitive explosive materials.
(4)(A) Where reblasting, washing, or removing explosive materials is unsafe or impracticable in a geophysical operation, the Division and surface owners shall be notified within 24 hours. The notice shall include the location, depth and the amount of the undetonated explosive material; and
(B) Following concurrence by the Division that retrieval of the explosive material in a misfired geophysical operation is impractical or unsafe, a substantial concrete cap capable of containing the explosion shall be placed above the explosive material at least 3 feet below the ground surface, or other permanent protection shall be installed.
(c) If explosive materials are suspected of burning in a hole, all persons in the endangered area shall move to a safe location and no one shall return to the hole until the danger has passed, but in no case within 1 hour.
(d) Holes shall not be drilled where there is danger of intersecting a charged hole of misfired explosives.
(e) No other work shall be performed in the danger area except that necessary to remove the hazard of the misfire. No other employees except the licensed blaster and the necessary crew shall be in the danger area when a misfire hazard is being removed.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5294. Coyote Hole Blasting.
(a) Electric lighting circuits shall not be permitted in a coyote hole while it is being loaded with explosives. Electric flashlights or cap lamps shall be used for illumination.
(b) In electrical blasting, the ends of leading wires shall be kept shorted until ready to blast. Circuits should be tested at least every 10 feet if stemming is placed in the cross-cuts, or before each explosives charge is placed.
(c) When detonating cord is used, a double line of cord with frequent cross ties shall be used throughout so that the detonating wave can reach each explosive charge from 2 independent sources.
(d) Coyote holes shall be backfilled tightly and for a sufficient length to prevent a blown-out shot.
(e) The area being loaded for blasting shall be plainly marked both in front and on top of the bank to be blasted with appropriate warning signs.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5295. Use of Safety Fuse -General.
(a) No fuse except safety fuse shall be used for fuse cap blasting.
(b) The average burning rate per foot of safety fuse used shall be determined by burning not less than three, 3-foot lengths of such fuse in open air at or near the blast area. Safety fuse which varies more than 10 percent from the manufacturer's stated burning range shall not be used.
(c) Notice shall be displayed conspicuously at the work location, stating the burning rate of safety fuse used.
(d) Damaged safety fuse shall not be used.
(e) If the roll of safety fuse has not been fully used and is stored for future use after blasting has been completed, the average burning rate shall be re-determined prior to use as required by subsection (b).
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5296. Safety Fuse Storage.
(a) In cold weather the safety fuse shall be warmed slightly before being uncoiled in order to avoid breaking or cracking.
(b) Safety fuse and igniter cord shall be stored in a place which is dry, cool, oil/grease free, and the relative humidity of the air is less than 80 percent.
(c) Safety fuse shall not be hung on nails or other projections that could cause a sharp bend to be formed in the fuse.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5297. Making Capped Fuses and Primers.
(a) In capping safety fuse, at least one inch shall be cut from the end of each coil of the fuse to be used to prevent damp fuse ends from getting into the cap.
(b) Blasting caps shall be kept in original or equivalent containers except as they are used for capping safety fuses.
(c) Only a ring-type cap crimper of standard design shall be used for attaching blasting caps to safety fuse.
(d) In capping fuse, the fuse ends shall be cut squarely with a sharp cutting blade. The capping operation shall be performed in a safe, dry location. The area shall be conspicuously posted with no smoking signs.
(e) A waterproof ring-type crimp or a compound especially prepared for waterproofing shall be used when necessary.
(f) A capped fuse shall not be attached to the primer cartridge by half-hitch.
(g) The safety fuse shall not be kinked when using the lacing method. The safety fuse shall lie in smooth curves as shown on the illustration. The cap shall be properly embedded along the axis of the cartridge.
Recommended Methods of Attaching Capped Fuse to Primer Cartridge
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5298. Non-Electric Blasting Systems.
(a) Safety Fuse Initiation System.
(1) Safety fuses shall not be ignited before explosive charges are in place.
Exception: Avalanche blasting.
(2) When blasting with safety fuse, consideration shall be given to the following: (A) the length and burning rate of the fuse; (B) the condition of the escape route; and, (C) the distance to a place of safety.
(3) Safety fuses shall not be used in any location, such as a shaft, raise or winz, where the lack of adequate nearby shelter and the distance of travel to a place of safety is such that there is a hazard to employees from flying rock and concussion.
(4) All safety fuses shall be cut sufficiently long to extend beyond the collar of the hole and in no case shall they be less than 3 feet in length. NOTE:At the usual rate of burning, a 3-foot length of safety fuse will fire a shot in about 2 minutes.
(5) Only single shots shall be fired when using 3-foot safety fuses. If more than one fuse is to be lighted at one time, such fuses shall comply with subsection (6) of this section.
(6) When lighting safety fuse, the fuses shall be so timed that no charge will detonate until at least 2 minutes after the last fuse in the blast area has been ignited.
(7) No one employee shall be permitted to ignite more than 12 safety fuses in succession. When 2 or more safety fuses in a group are lighted as one, by means of igniter cord or other fuse-lighting device, they may be considered as one fuse for the purpose of the subsection.
(8) If more than 3 safety fuses are lighted at one time, no person shall be permitted to enter the blast area until after a period of time equal to 2 minutes for each foot in the length of the longest fuse in the round or 15 minutes, whichever is the longest time.
(9) At least two employees shall be present when lighting fuses.
Exception: Avalanche blasting.
(10) Fuses shall be lit with devices approved for such purposes.
(b) Shock Tube Initiation System.
(1) Connections with other initiation devices shall be secured in a manner which provides for uninterrupted propagation;
(2) Factory-made units shall be used as assembled and shall not be cut except that a single splice is permitted on the lead-in trunkline during dry conditions; and
(3) Connections between blast holes shall not be made until immediately prior to clearing the blast site when surface delay detonators are used.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5298.1. Use of Detonating Cord.
(a) Detonating cord shall be selected consistent with the type and physical condition of the bore hole and stemming and the type of explosives used.
(b) Detonating cord shall be handled and used as an explosive.
(c) The line of detonating cord extending out of a bore hole or from a charge shall be cut from the supply spool before loading the remainder of the bore hole or placing additional charges.
(d) Detonating cord shall be handled and used with care to avoid damaging or severing the cord during and after loading, stemming and hooking up.
(e) Detonating cord connections shall be made in accordance with the manufacturer's recommendations. Knot-type or other cord-to-cord connections shall be made only with detonating cord in which the explosive core is dry.
(f) All detonating cord trunklines and branchlines shall be free of loops, sharp kinks, or angles that direct the cord back toward the oncoming line of detonation.
(g) All detonating cord connections shall be inspected before firing the blast.
(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.
(i) When connecting a blasting cap or an electric blasting cap to detonating cord, the cap shall be taped or otherwise attached securely along the side or the end of the detonating cord, with the end of the cap containing the explosive charge pointed in the direction in which the detonation is to proceed.
(j) Detonators for firing the trunkline shall not be brought to the loading area nor attached to the detonating cord until everything else is in readiness for the blast.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5299. Firing with Electricity -General.
(a) Before adopting any system of electrical firing, the licensed blaster shall conduct a thorough survey for extraneous currents, and all dangerous currents shall be eliminated before any holes are loaded. No electric blasting or preparation for electric blasting shall be done when stray electrical currents exceed 0.05 amperes.
Exception: Specialty electric blasting caps used as recommended by the manufacturer.
(b) Electric firing shall be done only with devices designed for initiating electric detonators.
(c) Electric detonators to be fired with blasting machines shall be connected in accordance with the number and circuitry limitations recommended by the machine or detonator manufacturer.
(d) Devices used for igniting electric detonators shall not cause arcing in the detonators. A circuit interrupter shall be used when arcing is a problem.
(e) All blasting wires shall be kept clear of electric lines, pipes, rails, and other conductive materials.
(f) That part of the blasting circuit leading from the firing switch to the blast area shall not be grounded.
(g) All low-voltage electric power lines within 50 feet of the holes to be loaded shall be removed or de-energized before an electric detonator or starter is brought into the blast area. Where this is not practical, a check for stray current shall be made with a proper instrument.
(h) The blasting circuit shall be tested with a blasting galvanometer or other device designed to test blasting circuits before firing the round.
(i) The blasting circuit shall remain shorted until the round is ready to test and fire.
(j) Electric detonators of different brands shall not be used in the same round.
(k) Where light and power circuits are used for blasting, keys to the shot-firing and safety switches shall be kept by the licensed blaster. When necessary to make repairs, extensions, or tests on the blasting or shot-firing lines, the licensed blaster or blaster in training shall unlock and remain at the switch until he or she relocks the switches or designates that responsibility to someone who reports back to the licensed blaster with the keys when work is completed. No preparations for loading or blasting shall be done until all switches are relocked and the keys back in the possession of the licensed blaster. At the end of the shift, the licensed blaster shall give the keys to the licensed blaster of the following shift. A duplicate set of keys should be kept by the superintendent under lock and key in the office. There shall be no other set of keys fitting these locks on the job site.
(l) Mobile radio transmitters shall be de-energized and effectively locked when less than 100 feet from electrical blasting caps that are not in their original container.
EXAMPLES OF BLASTING CIRCUITS Electric Detonators
TABULAR OR GRAPHIC MATERIAL SET FORTH AT THIS POINT IS NOT DISPLAYABLE
TABULAR OR GRAPHIC MATERIAL SET FORTH AT THIS POINT IS NOT DISPLAYABLE
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5300. Firing Switches.
(a) The firing switch shall conform to the following minimum standards:
(1) It shall be an externally operable switch, enclosed in a tight case provided with a lock.
(2) It shall be a double pole, double throw switch with the handle arranged to be locked in the "off" position only.
(3) It shall be provided with a bar for short-circuiting, but not grounding the leading wires when the switch is in the "off" position.
(4) Switches shall have adequate rating for the maximum voltage and current to be used.
(5) The service entrance switch fuse or circuit breaker rating shall be fused not exceeding 33 percent of the maximum calculated current requirement and will blow at 15 times the rated capacity in 1/20 of a second.
(6) The switch shall be mounted so that the handle is down when the switch is in the "off" position. The leading wires shall be attached to the blade terminals and the power line wires to the up-throw terminals.
(b) When firing by means of a light or power circuit, the circuit shall be open at all times in at least one place by an air gap of at least 5 feet underground and 15 feet on the surface, between the firing and the auxiliary switches at all times, except during the actual firing operation. The air gap shall be established by means of a cable and 2-pole plug and receptacle of adequate capacity. The plug shall be provided with a device, preferably of automatic type, to short-circuit the wires when the plug is removed from the receptacle.
(c) The shot firing switch shall be no less than 1,000 feet from the face of a tunnel if the tunnel length exceeds 1,000 feet.
(d) For tunnels less than 1,000 feet in length, the shot switch shall be outside the portal.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5301. Auxiliary Switches.
(a) One or more auxiliary switches shall be installed at the beginning of each branch circuit of the permanent leading wires.
(b) Such switches shall be as described in Section 5300 except that they need not be fused.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5302. Permanent and Temporary Leading Wires.
(a) All leading wires shall be type "S" cable or equivalent, or shall consist of 2 suitable insulated solid aluminum or solid copper wires.
(b) Permanent leading wires shall be installed in conduit or shall be strung on insulators and kept at least 5 inches apart.
(c) The conductor used to close the air gap shall be type "S" cable or equivalent.
(d) All leading wires shall have the capacity to carry the required firing current to the detonators. In no case shall a capacity of less than copper wire No. 14 American Wire Gauge or aluminum wire No. 12 American Wire Gauge be used, except No. 18 American Wire Gauge may be used for one electric blasting cap.
Recommended power firing systems for series and parallel series firing with no
circuit interrupter.
Recommended power firing systems for series and parallel series firing using a
circuit interrupter.
(e) All splices shall be well made and shall be so joined as to be electrical and mechanically secure. Splices shall be taped or otherwise effectively insulated.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5304. Blasting Procedure with Power and Light Circuits.
(a) Before connecting the leading wires to the leg wires, the licensed blaster shall make sure that the auxiliary switch or switches are locked in the "off" position, the air gap is open, the short-circuiting device is in place, and the firing switch is locked in the "off" position.
(b) If an electric circuit from a light or power source is used for firing shots, the electrical connections shall be made within an approved weatherproof enclosure.
(c) Leading or connecting wires shall be tested for the presence of stray electric current before they are attached to the leg wires. The test shall be made with an instrument designed and approved for this purpose. If stray current is detected it shall be eliminated before the connection is made.
(d) Before the leg wires are connected to the temporary leading wires, the blaster shall cause all persons to leave the blast area and proceed to a safe location.
(e) When the blast area is clear of all persons, the person responsible for firing shall proceed to the auxiliary switch, unlock it, and move the switch handle to the "on" position.
(f) After blasting, no one shall approach the blasted area until:
(1) The blasting switch has been locked in the "off" or "open" position, and,
(2) The blasting switch attachment plug has been disconnected from the electrical source, and,
(3) The blasting wires have been shorted together.
(g) In case the shot fails to fire (misfire) or the licensed blaster is not sure that the charges have fired, the licensed blaster shall lock the firing switch in the "off" position and open the air gap. The licensed blaster shall wait at least 30 minutes before proceeding to the auxiliary switch which shall be locked in the "off" position before entering the blast area.
(h) Only the crew actually necessary for the loading and connecting-up operation shall be at the face during operations.
(i) No unnecessary work shall be done at the face during or after loading before the shots are fired.
BLASTING CIRCUIT DIAGRAM
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5305. Electric Blasting Devices and Electric Blasting Machines.
(a) All blasting devices and blasting machines shall be in the charge of the licensed blaster-in-charge and no other person shall connect the leading wires to the blasting machine or other blasting devices.
(b) Leading wires shall not be connected to blasting devices or blasting machine until all steps preparatory to firing have been completed and all persons proceed from the blast area to a safe location.
(c) After firing the round, the licensed blaster-in-charge shall immediately disconnect all wires from blasting devices or blasting machines and short-circuit the leading wires.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 5306. Electric Blasting in Proximity with Radio Transmitters.
(a) A sign shall be posted reading, "BLASTING AREA TURN OFF 2-WAY RADIOS AND CELLULAR TELEPHONES," "BLASTING ZONE 1000 FT" and "END BLASTING ZONE." Lettering of the sign shall be at least 4 inches in height and 5/8-inch stroke on a sharply contrasting color background. The sign shall be displayed prior to installation of electric-sensitive devices, during loading and during blasting operations. Note:Where applicable, see State of California, Department of Transportation, Traffic Manual, Chapter 5, Traffic Controls for Construction and Maintenance Work Zones for specific sign requirements.
(b) Signs shall be posted approximately 1,000 feet from the blasting area on all public access.
(c) Electric blasting operations shall not be conducted closer to any operating mobile or fixed radio, television, or radar transmitter than the distances shown in the following tables:
Table 1 Recommended Table of Distances for Commercial AM Broadcast
Transmitters (0.535 to 1.605 MHz)
Transmitter Power [FN1] Minimum Distance
(Watts) (Feet)
Up to 4,000.............. 720
5,000.................... 800
10,000................... 1,130
25,000................... 1,790
50,000 [FN2]............. 2,500
100,000.................. 3,600
500,000.................. 8,000
_______
[FN1] Power delivered to the antenna.
[FN2] 50,000 watts is the present maximum power of U.S. broadcast transmitters in this frequency range.
Table 2 Recommended Distances for Transmitters Up to 50 MHz (Excluding AM
Broadcast) Calculated for a Specific Loop Pickup Configuration [FN1]
[FN2]
Transmitter Power [FN(3)]) Minimum Distance
(Watts) (Feet)
100....................................... 790
200....................................... 1,120
500....................................... 1,770
1,000..................................... 2,500
1,500..................................... 3,070
5,000..................................... 5,590
50,000.................................... 17,700
500,000 [FN(4)]........................... 55,900
___________
[FN(1)] Based on the configuration with the blasting machine being the
component of the blasting circuit closed to the transmitter, using 20.8 MHz,
which is the most sensitive frequency.
[FN(2)] This table should be applied to International Broadcast Transmitters
in the 10-25 MHz range.
[FN(3)] Power delivered to the antenna.
[FN(4)] Present maximum for International Broadcast.
Table 3 Recommended Distances of Mobile Transmitters and Cellular Telephones
Including Amateur and Citizens' Band
MINIMUM DISTANCE VHF UHF
(Feet)
VHF 144 to 148 450 to 470
MHz MHz
Transmitter MF HF 35 to 36 MHz Amateur Public Use
[FN(1)] Public Use
Power 1.7 to 28 to 42 to 44 MHz 150.8 to Cellular T-
3.4 29.7 Public Use 161.6 MHz elephones
MHz MHz
(Watts) Industr- Amateur 50 to 54 MHz Public Use Above 800
ial Amateur MHz
1 15 47 37 12 8
5 33 105 82 27 18
10 46 148 116 38 25
50 102 331 259 85 55
100 144 468 366 120 78
180 [FN(2)] 193 627 491 161 104
200 204 661 518 170 110
250 228 739 579 190 123
500 [FN(3)] 322 1,045 818 268 174
600 [FN(4)] 353 1,145 897 294190 (continued)