WAC 296-52-805   Hand charge makeup methods.  General. The department shall recognize two permissible methods concerning hand charges for avalanche control blasting. The descriptions and requirements for each method are contained in this section.

Note:

A well-designed and constructed hand charge makeup room can enhance the correct assembly of explosive components and reduce the incidences of misfires from incorrect makeup or moisture.

     (1) Method I. Makeup at the blast site.

     (a) The ignition system shall consist of a nonelectrical blasting cap and highest quality water resistant safety fuse, or detonating cord, assembled as recommended by the manufacturer.

     (b) Detonating cord shall be used to connect separated multiple-charge blasts.

     (c) No other ignition system shall be permissible on hand-placed or hand-thrown avalanche control charges unless variance is granted by the department.

     (d) Caps shall be installed on correct length fuses prior to being transported out onto control routes.

     (e) Caps shall only be crimped with a crimper tool approved for that purpose.

     (f) Assembling caps and fuses shall be done in a warm, dry, well-lighted environment. The location used for assembly shall not have flammable fuels, flammable gases, or explosives present where accidental detonation of the caps could create a secondary ignition or detonation hazard.

     (g) Each cap shall be protected by a styrofoam shield or the equivalent before being placed in an avalanche control pack for transportation.

     (h) A fuse igniter shall never be attached to a fuse until the fuse and cap assembly is installed in the hand charge at the blast site and the control crew is fully prepared to ignite the charge.

     (i) All 1.1 explosives shall be attended as defined in this chapter at all times when the explosive is out of the Type 1 or 2 storage magazine.

     (j) Disbursement of explosive charges from the Type 1 or 2 storage magazine into avalanche control packs shall be done outside the storage magazine. Records shall be maintained for all explosives disbursed.

     (k) Caps, cap and fuse assemblies, armed hand charges, or fuse igniters shall not be carried into or stored in a Type 1 or 2 magazine which contains 1.1 explosives.

     (2) Method II. Hand charge makeup room. This method is different from method I primarily in that the fuse and cap assembly is installed in the explosive charge while inside a special makeup room. The assembly procedure shall be as follows:

     (a) Install caps on correct length fuses with an approved crimper tool before explosives are brought into the makeup room.

     (b) The cap and fuse assemblies shall not be combined with explosives to form hand charges until just before the intended time of distribution.

     (c) Only nonsparking skewers shall be used to punch holes in an explosives cartridge.

     (d) The fuse shall be laced or taped in position after inserting the cap in the charge.

     (e) Each hand charge shall be placed in an explosives box or avalanche control pack immediately after assembly is completed.

     (f) No spark-producing metal tools shall be used to open explosives containers.

     (g) Fuse igniters shall never be attached to a fuse or a hand charge until the hand charge is at the blast site and the control crew is fully prepared to ignite the charge.

     (3) Makeup room requirements, procedures.

     (a) Construction requirements.

     (i) Makeup rooms located in accordance with the American Standard Quantity and Distance Tables for storage shall not require construction of reinforced concrete walls, floors, and doors. All other requirements of this chapter shall be applicable for such facilities.

     (ii) Floors and walls. The floor and walls shall be constructed of reinforced concrete not less than eight inches thick. The rebar shall be not less than one-half inch diameter and shall be spaced on twelve-inch vertical and horizontal centers. The rebar shall be bent at a ninety degree angle and extend a minimum of twenty-four inches into the adjoining floor or wall to secure each floor and wall joint.

     (iii) Roof. The roof is not limited to specific materials but shall provide both weather protection and standard snow loading protection for the region.

     (iv) Access door(s).

     (A) If a hinged door mounting is utilized, the hinge shall be mounted on the inside so that the door opens into the makeup room. In the fully closed position, in position to be locked, the door shall be a minimum of two inches larger than the access opening on all sides.

     (B) If a flush door mounting is utilized, the door shall be mounted with a two-inch decreasing taper on all sides of both the door and the concrete access opening to form a wedge seal.

     (C) If a sliding door mounting is utilized, the mounting apparatus shall be on the inside of the makeup room and the door shall be a minimum of two inches larger than the access opening when the door is fully closed.

     (D) Makeup room door may be either:

     (I) Constructed to the same structural integrity and mounting requirements of (A) through (C) of this subsection; or

     (II) Constructed of plywood not less than two inches thick and overlaid on the outside with a steel plate not less than one-eighth inch thick.

     (III) If a door which complies with (II) of this subsection is used, a berm or barricade shall be installed within six feet of the door. The berm or barricade shall extend at least as high as the top of the door and shall be a minimum of two feet wider than the door on both sides of the door.

     (E) For security purposes, one steel padlock having at least five tumblers and a case hardened shackle of at least three-eighths inch diameter is sufficient for locking purposes. Hinges and hasps shall be attached so that they cannot be removed from the outside when in the closed position and with the lock in place.

     (v) Interior finish. The inside of all makeup rooms shall be finished and equipped to the following minimum requirements:

     (A) Construction shall be fire resistant and nonsparking up to the top of the walls. Nails or screws shall be countersunk, blind nailed, or covered.

     (B) Lighting shall be by N.E.C. explosion-proof rated fixtures and all wiring shall be in sealed conduit.

     (C) Control switches shall be outside the makeup room.

     (D) No electrical outlet boxes are permissible inside the room.

     (b) Restrictions.

     (i) Smoking, matches, open flames, or flame- or spark-producing devices shall not be permitted inside the makeup room.

     (ii) Flammable liquids or flammable compressed gases shall not be stored in the makeup room.

     (iii) Signs limiting entry to authorized personnel shall be posted on the door(s).

     (iv) A sign stating the occupancy rules shall be posted inside the makeup room where it is clearly legible upon entering the room. The sign shall post the following rules:

     (A) Occupancy shall be restricted to specifically authorized personnel;

     (B) Smoking, matches, flame- or spark-producing devices, tools or equipment shall not be permitted in the room at any time when explosives or explosive components are present; and

     (C) Flammable fuels or compressed gases shall not be permitted inside the room nor stored within fifty feet of the room.

     (v) Heating units shall be limited to:

     (A) Forced air systems with the heating unit located outside the room.

     (B) Steam systems of 15 psig or less.

     (C) Hot water systems of 130°F or less.

     (D) The radiant heating coils and piping for steam or hot water systems shall be protected so that explosives cannot come into contact with them.

     (E) Heating ducts shall be installed so that the hot air does not discharge directly on explosives.

     (F) The heating system used in a makeup room shall have controls which prevent the ambient room temperature from exceeding 130°F.

     (vi) The makeup room shall be equipped with a portable fire extinguisher of at least 2A-20BC rating.

Note:

For additional requirements relating to portable fire extinguishers see WAC 296-800-300.

     (vii) Ventilation.

     (A) The makeup room shall be equipped with a ventilation system capable of maintaining a minimum rate of three air exchanges per hour during all times when explosives are present in the room.

     (B) Fans and controls shall be located outside the makeup room and shall be of a type approved for this service.

     (C) The lighting circuit control shall also activate the ventilation fan and the ventilation fan shall be operated whenever personnel are in the room.

     (D) Exhaust ventilation shall be arranged to discharge into outside air, not into an enclosed structure.

     (viii) The floor or exterior walls may be constructed with duct openings for heating and ventilation purposes provided that:

     (A) Each duct opening is not greater in volume than seventy-two square inches;

     (B) The combined number of duct openings shall not exceed three;

     (C) Duct openings shall be located within twelve inches of the floor or ceiling;

     (D) The exhaust duct opening shall not be located on the wall above the makeup workbench.

     (c) Practices and procedures.

     (i) When explosives are present in the makeup room, entry into the makeup room shall be restricted to trained and authorized personnel.

     (ii) The access door(s) to the makeup room shall be kept locked or bolted from the inside while employees are assembling explosives.

     (iii) The entire makeup room shall be kept clean, orderly, and free of burnable rubbish.

     (iv) Brooms and other cleaning utensils shall not have any spark-producing metal parts if used when explosives are present.

     (v) Sweepings and empty explosives containers shall be disposed of as recommended by the explosives supplier.

     (vi) Repair activities which utilize spark-producing tools shall not be conducted on any part of the makeup room while explosives are present.

     (d) Storage of explosives.

     (i) A makeup room shall not be used for the unattended storage of 1.1 explosives.

     (ii) A makeup room which meets all requirements of this chapter may contain a Type 3 storage facility, for one thousand or less blasting caps.

     (iii) A Type 3 storage facility shall be constructed according to the requirements in WAC 296-52-70030 through296-52-70040 .

     (A) A Type 3 storage facility shall be fire resistant and theft resistant. It does not need to be bullet resistant and weather resistant if the locked makeup room provides protection from weather and bullet penetration.

     (B) Sides, bottoms, and covers shall be constructed of not less than number twelve gauge metal and lined with a nonsparking material.

     (C) Hinges and hasps shall be attached so that they cannot be removed from the outside.

     (D) One steel padlock having at least five tumblers and a case-hardened shackle of at least three-eighths inch diameter is sufficient for locking purposes. The lock and hasp is not required to be equipped with a steel hood.

     (e) Location.

     (i) The makeup room shall be located in accordance with the American Quantity and Distance Separation Tables as adopted in chapter 70.74 RCW, Washington State Explosives Act and this chapter except under conditions as indicated in this section.

     (ii) Where locating the makeup room in accordance with the quantity and distance separation table is impractical because of bad weather accessibility, rough terrain, or space availability:

     (A) Upon application the department will issue a variance enabling location of the makeup room, by mutual agreement, at the safest possible location within the limitation of the individual base area.

     (B) The safest possible location will be the location most isolated from assembly areas and buildings that are inhabited with application of additional protection measures such as:

     (I) Berming.

     (II) Locating natural obstructions or buildings that are not inhabited between the makeup room and assembly areas and buildings that are inhabited.

     (III) Limitations on the total quantity of explosives in the makeup room at any one time.

     (iii) Makeup rooms designed to hold the boxes of explosives awaiting makeup and the madeup explosives in avalanche control packs awaiting distribution may be located using the total quantity of explosives allowed at the makeup table at any one time as the referenced quantity of explosives provided.

     (A) The makeup room is located in accordance with the American Quantity and Distance Separation Tables as adopted in chapter 70.74 RCW, Washington State Explosives Act and this chapter for the referenced quantity of explosives at the makeup table.

     (I) This separation shall apply only to human proximity to the makeup room and only at such time as there are explosives in the makeup room.

     (II) When the makeup room does not contain explosives the separation tables shall not apply.

     (B) The concrete walls of the room are designed to withstand the explosion of the total amount of the referenced explosives.

     (I) The concrete walls must be constructed in accordance with specifications designed and certified by a licensed engineer; or

     (II) The concrete walls must be constructed to the specifications of Department of the Army TM5-1300 "Structures to Resist the Effects of Accidental Explosions" designed to produce walls which will withstand explosion of the referenced quantity explosives.

     (C) The boxes of explosives awaiting makeup and the madeup explosives in avalanche control packs awaiting distribution are located behind separate concrete debris barrier walls which will ensure that detonation of these explosives will not occur if the explosives at the makeup table detonate.

     (I) The concrete debris barrier wall must be constructed in accordance with specifications designed and certified by a licensed engineer; or

     (II) The concrete debris barrier wall must be constructed to the specifications of Department of the Army TM5-1300 "Structures to Resist the Effects of Accidental Explosions" to produce a barrier which will not allow detonation of the explosives awaiting makeup and distribution should the referenced quantity of explosives detonate.

     (III) Access from the makeup table to the area behind the concrete debris barrier walls shall not be doored. The concrete debris barrier walls will be designed so that the access way from the makeup table to the area behind the concrete debris barrier wall will deflect debris from an explosive blast by inherent design.

     (D) The roof shall be designed so that the resistance to an interior explosive blast will be negligible.

     (iv) A full containment makeup room may be located anywhere and must meet the following requirements:

     (A) The makeup room must be constructed in accordance with a licensed explosive engineer's approved design.

     (B) The total amount of explosives in the room at any time must not exceed the design limit of the room.

     (C) The makeup room cannot be used for storage.



[Statutory Authority: RCW 49.17.010, 49.17.040, 49.17.050, 49.17.060. 06-19-074, § 296-52-805, filed 9/19/06, effective 12/1/06.]