PRECAUTIONARY MEASURES FOR BLASTING

1.0       PURPOSE:

This section covers the various precautionary measures for blasting operation, which shall be implemented during blasting without any exception to prevent injury/accident.

2.0       SCOPE

The section covers the minimum requirements of the blasting operation carried out at projects.  This does not include all types of blasting operation.  The company shall fully comply with the regulation of respective government agencies having jurisdiction there have and comply applicable safety rules of Chief Controller of explosive of the region.

3.0       RESPONSIBILITIES

As per section II i.e. from 2.1 to 2.10.

4.0       PRECAUTIONARY MEASURES

After relevant permissions from respective Government Authorities are to be obtained.. The Safety procedure submission and approval of blasting procedure shall be done. Adequate and trained personnel shall be mobilized. The storage techniques for explosives and speculating the norms for use of explosives including preparation of primers, charging of holes and electrical firing shall be established. It also includes the post blasting precautionary measures i.e. misfires, cleaning of the area from debris/rock, pebbles etc. The company will employ only such workmen who are experienced in the type of work to be performed. To supervise, handle and use of explosives. Before the start of actual work, trial blasting shall be performed. Company shall also obtain permits for storage and use of explosive and comply with the stipulated laws of respective Government agencies. Prior to commencement of blasting company shall inform to client / Govt. authorities /property owners/adjacent work crews.

4.1       OPEN BLASTING:

            Where blasting is to be carried out 50 meters away from any structure either above ground or below ground and perform a trial blast for approval from client/Government agencies.

4.2       CONTROLLED BLASTING:

Where blasting is to be carried out between 50m and 15m from existing structure, either above ground or underground. Trial blasting shall be done for approval from client/Government agencies.

• RESTRICTIONS:

No blasting shall be allowed within 15 meters of any existing structure.

4.4       MATERIALS:

All material such as explosives, detonators, fuses, tamping materials etc. that has proposed to be used in blasting operations shall have the prior approval of client/Government agencies.

            FUSE:

Fuse with only one protective coat is prohibited. The fuse shall be sufficiently water resistant as to be unaffected when immersed in water for 30 minutes.

Fuses shall be inspected and the moist, damaged or broken one shall be discarded.

4.5       STORAGE

Company shall build a magazine for storing the explosives. The site capacity shall be subject to approval by the inspector of explosives/client. As a rule, the explosive should be stored in a clean, dry, well ventilated and fireproof building at an isolated site.

Adequate security shall be provided to prevent unauthorized entry into the storage area. A notice shall be hanged near entrance prohibiting the entrance of unauthorized person. A careful day to day account of the use of explosives shall be kept in a register and shall be produced for inspection as and when required. Explosives shall be stored and used chronologically to ensure that the ones received earlier are being used first.

4.6       TRANSPORT OF EXPLOSIVES

For the transport of explosives and detonators from store to site, closed and strong containers made of soft material such as timbers, zinc, copper, leather shall be used. Explosives and detonators shall be carried in separate boxes, tightly closed and transported separately. For the conveyance of primers, special containers shall be used. A make-up house shall be provided at each working place in which experienced personnel shall make up cartridges. The make- up house shall be separated from other buildings and only electric storage battery lamps shall be used in this house.

4.7       PREPARATION OF PRIMERS

The primers shall not be prepared near open flames or fires. The work of preparation of primers shall always be entrusted to the qualified and approved personnel. Primers shall be used as soon as possible after they are ready.

• DRILLING & CHARGING OF HOLES

After completion of drilling work, charging will commence.

4.9       ELECTRICAL FIRING    

Special apparatus shall be used as a source of current for the firing operation. Power lines shall not be tapped for the purpose. The keys of the firing apparatus shall be kept with the supervisor in charge only. For blasts in one series, only detonators of the same manufacturer and of the same group of electrical- resistance shall be used. The firing cable shall have a proper insulating cover to avoid short-circuiting or to contact with water or metallic parts or rock. The use of earth as a return line shall not be permitted. Before firing, the circuit shall be checked by a suitable apparatus by an approved person.

After firing whatever with or without an actual blast, the contact between the firing cable and the source of current shall be cut off.

During storms, charging of electrical detonators shall be suspended. The charges already placed into the holes shall be blasted as quickly as possible after taking all the safety precautions and giving necessary warning signals. If this is not possible, the site shall be abandoned till the storm has passed.

4.10     SAFETY PRECAUTIONS

            Trained workmen will permit blasting only under the supervision of competent and licensed persons.

• Company shall ensure all supervisors and workmen in charge engaged in make- up, handling, storage and blasting work.

• The storage shall be under the charge of a very reliable person and if necessary police inquiries being made.

• The magazine shall not be opened during the approach of a thunderstorm and no person shall remain in the vicinity of the storage area during such period.

• Shoes without nails shall be kept in the magazine and wood tub or cement filled container with water shall be fixed near the door of the magazine.

• Measures shall be taken to ensure that persons entering the magazine should wear magazine shoes and be careful. Do not allow the magazine shoes to touch the ground outside the floor.

• Do not allow any dirt or grit to fall on the clear floor.

• No matches or inflammable material shall be allowed in the magazine. Light shall be obtained from an electric storage battery lamp.

• No tools other than copper, brass shall be allowed inside the magazine, oily cotton rags, waste and articles liable to spontaneous ignition shall not be allowed inside the magazine.

• Boxes of explosives shall not be throw down or dragged along the floor and shall be stacked on wooden trestles. Open boxes of explosives shall never be exposed to the direct rays of the sun. Empty boxes or loose packing material shall not be kept inside the magazine.

• The magazine shall have a lightning conductor, which should be periodically tested.

• All detonated explosives shall be disposed of in an approved manner as per explosive rules. All the records of such disposal shall be maintained.

• While charging, open lamps/flames shall be kept away.

• Only wooden tamping rods without any kind of metal on them shall be used.

• After drilling only one cartridge shall be gently inserted with the tamping rod. Blasting shall be carried out during fixed hours of the day. The hours once fixed shall not be changed without the prior information.

• The site of blasting operations shall be prominently demarcated by red danger flags. The order of the fire shall be given only by the supervisor in charge of the work and this order shall be given only after giving the warning signal three times, so as to make all the labour, watchmen to reach safe shelter and ensure that nobody is within the danger zone.

• A whistle with a distinctive note shall be used to give the warning signal. The whistle shall not be used for any other purpose.

• All the roads and footpaths leading to blasting area shall be kept under strict vigilance.

• In case blast has failed to fire or is delayed, sufficient time shall be allowed to lapse before entering the danger zone. An only licensed person alone shall go to inspect the misfire.

• Drilling near the hole that has misfired shall not be permitted until the supervisor has carried out the following operations. The supervisor (licensed person) shall very carefully extract the tamping with a wooden scraper or use jet of water/ compressed air and withdraw the fuse attached.

• If it is not possible another hole may then be drilled at least 9 inches away and parallel to it. This hole should then be charged and fired.

• If a misfire has been found due to the defective detonator or explosive, the whole quantity must be returned to the authority for inspection.

• Re-drilling of the hole that has misfired either wholly or part shall not be permitted.