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STORAGE AND USE OF EXPLOSIVES 1001 General Reference may be made to the following for detailed provisions:
IS: 4081-1986: Safety code for blasting and . related drilling operations. c) Other rules and special instructions issued by Railway Administration or by State Government from time to time. 1002 Issue of Instructions on Use of Explosives Explosives are used in the following cases:- a) for clearing boulders which fall on the railway line, as in ghat sections; b) for quarrying rock; c) for widening rock cuttings; d) for deepening wells; e) for cuttings in rock, f) excavation of foundations in rock; and g) construction of tunnels. The Railway Administration shall prescribe the type and quantity of explosives to be kept with inspectors for removing boulders falling on running lines. The Administration shall also prescribe the locations for stocking these explosives magazines in the sub-division. Blasting works may be carried out departmentally or by contract; in either case it should be ensured that competent qualified staff are engaged and safe working practices are employed. If the work is done through contract, the Contractor shall be in possession of a license to purchase, store and use explosives. Blasting operation can be carried out only through persons (Blasting Mates) who are authorised by the appropriate Department. For major works, the Railway Administration will draw up special instructions which should cover every aspect of each operation and be illustrated with sketches where necessary; the instructions should include:- (i) Duties of Blasting Mates and other staff. (ii) Description of materials used for blasting, such as explosives, detonators, safety-fuses, blasting cables, joint adapters, fuse lighters, exploders and crimpers. (iii) Collection and transport of materials, (iv) Testing of materials used for blasting. (v) Procedure and methods of boring and charging of holes and blasting for each type of explosive. (vi) Imposition and removal of traffic and/or power blocks. (vii) Safety-distances. (viii) Protection of track and structures during blasting operations. (ix) Precautions before, during and after blasting. (x) Danger and all clear signals before and after a blasting operation. (xi) Submission of periodical progress reports. (xii) Custody and storage of explosives in magazines and their accountal. 1003 Observance of Rules a) Possession of explosives shall bet covered by a license as required by the extant Explosive Rules. b) The Divisional/Dy. Chief Engineer, Assistant Engineer and the Section Engineer (Works) shall be responsible to ensure that rules issued by the Government and the Administration in regard to the storage and use of explosives on works are strictly obeyed. The Inspector of Explosives and the District Magistrate have powers to inspect all magazines. All staff should willingly assist in such inspections. The Divisional/Dy. Chief Engineer and Assistant Engineer should, by frequent check, personally satisfy themselves that all staff handling explosives are in possession of and understand the rules and any subsequent modifications thereto. c) The Assistant Engineers and Section Engineer (Works) within whose jurisdiction magazines are situated, should make a special mention of these in their handing over notes and ensure that their relievers understand the orders relating to these magazines. Mention should also be made in the handing over notes of any modifications which may have been suggested by the Inspector of Explosives or District Magistrate on his last inspection and whether these have been carried out. 1004 Carriage of Explosives Assistant Engineers and Inspectors should make themselves acquainted with the instructions contained in the I.R.C.A. Red Tariff No.16 "Rules and rates for the conveyance by rail of explosives and other dangerous goods". If carried by a road vehicle, the vehicle should have the necessary licence issued for the purpose. 1005 Protection to Trains and Railway Property a) In vicinity of railway line. Blasting operations within 100 metres of a running line should normally be carried out under block protection. Tracks within 60 metres of the rock to be blasted should be protected by covering with old sleepers which should be removed after the blasting is over and before removal of the block. When the blasting operation is carried out without imposition of the block, the Permanent Way Inspector shall ensure protection to trains in such a case, no blasting should be done within half-an-hour of the time when any train is expected to pass. b) In vicinity of buildings.- When any blasting operation is carried out within 100 metres of a building, the Works Inspector shall be present to ensure that special precautions, as may be prescribed by the Divisional/ Dy. Chief Engineer or the Assistant Engineer or as stipulated by the licensing authority, are taken and that the necessary warning is given to the inhabitants. 1006 Precautions to be Observed During Blasting The Blasting Mate shall be responsible:- a) To see that when blasting is conducted in the neighbourhood of a public or private road or building, or of any place where there may be people who would be endangered, experienced Watchmen are sent, with red flags, to stop traffic or warn persons. These Watchmen would be warned from the workspot, of the commencement and cessation of blasting operations: b) To see that, before blasting commences, all persons except those who are actually to light the fuses, are warned by the repeated striking of an empty tin or blowing of a siren and are at a distance of not less than 150 metres and that, in special cases, suitable extra precautions are taken; c) To see that, in order to avoid damage to structures (such as girder bridges and telegraph wires) which may be in close proximity to the blasting spot, only shallow bore-holes are drilled and light charge used or vary the angle of bores to control the blast; d) To select and instruct carriers of the explosives, detonators and safety fuse after they have been drawn from the magazine; e) To ensure that no one interferes in his absence with any explosive, detonators or caps already drawn by him from the magazine; f) To see that neither himself nor any person within 10 metres of himself smokes while he is conveying, handling or using explosives; g) To see that bore holes are of such a size that cartridges can easily pass down them; that bore holes are clear of all debris before a cartridge is inserted, that charging is done by himself and the position of the charged holes are noted carefully. h) To drop several centimetres of tamping of sand or clay on top of the primer cartridge before beginning to stem or press and that this tamping is gently pressed down on top of the primer without the use of force; Note:- The primer-cartridge is the cartridge in which the detonator or cap and fuse are attached and is usually fixed as the last cartridge of the charge. i) To see that the safety fuses of the charged holes are lighted in his presence and have properly ignited; j) To compare the number of shots actually heard with shots intended to be fired and to carefully inspect the work after blast and satisfy himself that all holes have exploded and the broken rock does not contain any unexploded cartridge or pieces of cartridges; k) to take precautions as given below in cases of mis-fires (i) if a charge has apparently missed fire, to immediately warn all present and see that no person is allowed to go near it for an hour, (ii) if a charge misses fire, to examine the hole and mark a red cross over it, (iii) to see that a shot that has missed fire is not bored or picked out; that no further charge is introduced into the hole ; (iv) to determine the direction of the hole for which purpose a few centimetres (inches) of tamping may, if necessary, be picked out and a stick placed in the mis-fired hole and to drill, after 60 minutes have passed, a fresh hole near the charge which has missed fire and that this is done at a safe distance from the former hole and in such position and direction that the boring tool cannot come in contact with the explosive which has missed fire. The Blasting Mate must not leave the spot on any account whatsoever until the second hole (which should explode the old charge) has been fired. He must carefully examine the result and continue the operation, if necessary, until the original charge has exploded. I) to make sure that there is only one key to the exploder and that this is in his pocket when he has to leave the exploder. This is necessary for his own protection. 1007 Misfires with Electrical Method of Firing a) If after complying with para 21 of the Indian Metalliferous Mines Regulations, the Official in-charge of the blasting operations at a site ascertains that a misfire has occurred, he will immediately prevent any one from approaching the site whose presence is not absolutely essential. He will re-examine the connections, check the wiring or re-wire as he thinks fit and will try again to fire the charge by electrical means. b) Should he be unable to fire the unexploded charge (s) by electrical means, he will then comply with paras 82-84 of the above Regulations, which are reproduced below, using the means considered the most suitable:- "82. No person shall bore out a hole that has once been charged or attempt to withdraw a charge either before firing or after a misfire or deepen or tamper with empty holes or sockets left after blasting. "83. When a misfire occurs, a portion of the tamping may be sludged out with compressed air or water under pressure, but no kind of metal tool shall be used for this purpose. The hole shall thereafter be reprimed and fired. "84. No person shall drill or cause or permit to be drilled any hole within 300 mm of a misfired hole, and care shall be taken to drill the new hole in such a direction that there is no danger of touching the unexploded charge. The new holes shall be bored in the presence of an authorised shot-firer and he shall be present during operation undertaken for the removal of debris lying within 2 metres of the misfired hole. A careful search amongst the debris shall be made for cartridges and detonators, if any. c) Since with the electrical method of firing, it is possible for one shot to explode and blast out the rock in which an adjacent charge has been placed but which has not exploded, the Official-in-charge is responsible, at the end of each blast, for examining the working face minutely to detect whether any charges have misfired in this manner. If he considers that this may have been possible, a careful search must be made in the debris for the unexploded detonator. 1008 Explosives Disposal a) No explosive shall be abandoned. These shall be disposed off or destroyed strictly in accordance with the approved methods and in doing so the manufacturers or the appropriate authority shall be consulted. b) Explosives, caps, boxes liners or material used in packing of explosives shall not be left lying around in places to which children or unauthorised persons or livestock can have access. c) Paper or fibrous material employed in packing explosives shall not be put to any subsequent use. Such material shall be destroyed by burning in the presence of a responsible person. 1009 Destruction of Explosives The destruction of explosives should, in all cases, be supervised by the Assistant Engineer. When destroying explosives, the following instructions should be strictly adhered to:- a) Black powder- Black powder should be thrown into water, preferably hot water, which dissolves out the saltpetre and renders the explosive harmless. An alternative method is to lay it out in a train and fire this from one end by means of a piece of safety fuse, but if more than one train is laid, care should be taken to lay the second at such a distance from the other as to run no risk of one being fired by the heated ground of another. b) Dynamite and other similar explosives -Not more than 2.5 Kg. of the explosive should be destroyed at a time. A clear space of ground, free from dry grass, about 100 square metres should be selected at least 800 metres away from buildings and dwelling places. A line of shavings or dry grass, about 450 mm wide and at least 100 mm thick, should then be laid down. The direction of the line should be at an angle of about 45o to the direction of the wind. The work should not be undertaken on a day when the wind would be strong enough to disturb or blow away the shavings. This line of shavings or dry grass should then be adequately sprinkled with kerosene oil to ensure its burning continuously. The cartridges with the wrappers opened and unrolled should then be placed in a continuous line not more than 2 abreast with an interval of 25 mm between each line of cartridges and with the cartridge wrappers or other paper lightly placed below them. The cartridges should be placed at about 6 metres from the weather end of the line of shavings, at the extreme weather end of which will be placed an adequate length of safety fuse. To ensure the ignition of the shavings, it may be found necessary to place a small quantity of cotton waste soaked in petrol adjacent to the end of the safety fuse and on the shavings. The .safety fuse should then be lighted and the operator should retire quickly to a safe distance when after a short time the dynamite will burn steadily without exploding. c) Detonators -Surplus detonators should be disposed of by throwing them, one at a time, into a deep pool of a river or the sea. An alternative method is to soak them thoroughly in light mineral oil for 48 hours and then destroy them by throwing them one at a time into a fire with due precautions. d) Safety fuse - Safety fuse should be destroyed by burning in lengths in the open. ••••••• |