Electrical Accidents PDF

CHAPTER V ELECTRICAL ACCIDENTS 10500 Electrical Accident An electrical accident is caused directly or indirectly due to electrical causes, that is, it includes any electric shock or electric burn, whether minor, major or fatal and whether suffere...

CHAPTER V ELECTRICAL ACCIDENTS 10500 Electrical Accident An electrical accident is caused directly or indirectly due to electrical causes, that is, it includes any electric shock or electric burn, whether minor, major or fatal and whether suffered by railway servants or others. A person may suffer electric shock by coming in contact with :- 1. Live mains. LT or HT. 2. Overhead lines, which although made dead by isolation at both ends still develop high potentials on account of electro-static or electro-meganetic induction due to parallelism with other high voltage live lines, or due to lightning discharges during thunderstorms: 3. Parts which have become live due to leakage either because of low insulation resistance of the electrical windings, high earth resistance of discontinuity of the earthing lead to the body: 4. Areas which develop a high potential gradient such as near an earth electrode through which a fault current is flowing, and is insufficient to blow the fuse or cause the circuit breaker to trip. In any well-maintained installation, no electrical accidents should occur. Every accident can, in the final Analysis, be traced to one or more of the following causes, if properly probed into:- 1. Disregard or non-observance of the prescribed rules laid down: 2. Ignorance of rules and insufficient training of staff: 3. Carelessness, casual and indifferent methods of working, including improper earthing indicating inadequate supervision: 4. Faulty protective equipment and poor maintenance: 5. Over-confidence or sheer laziness: 6. Old habits of working on non-electrified lines: 7. Misunderstanding of instructions: 8. Inadvertence. Every rule prescribed is the result of experience gathered over the years by several persons, and owes its origin to some electrical accident or damage to equipment observed in the past. Rules and procedures prescribed should therefore, be taken seriously, and never allowed to fall into discuss. To enable a better appreciation of the need for meticulous observance of the safety rules prescribed, brief particulars of several case histories have been presented in para 10511. 10501 Electrical Accidents – Action to be taken 1. In the event of an electrical accident or the possibility of an accident, the senior most official present at the site of the accident shall take the following preliminary precautions immediately:- INDIAN RAILWAYS-AC TRACTION MANUAL –VOLUME I a) If there is a breakdown of the overhead lines, he should arrange to cordon off the area, so that no one else may get injured. He shall also warn Drivers of trains. b) Arrange to cut off supply to the installation concerned by telephoning to the Traction Power Controller or the nearest Electrical Department official, and simultaneously arrange for an Authorised person to the spot. No one may attempt to rescue an electrocuted person untill power supply has been cut off. b) Send for medical assistance. In the meanwhile, after the injured person, if any, has been separated from the electrified lines, he shall arrange to render first aid; artificial respiration should be started immediately if the patient is not breathing. 2. Immediately on arrival at site, the Authorised Electrical Department Official (Foreman/Chargeman), shall first check and made sure that the steps mentioned have been correctly taken. After attending to the injured and clearing the lines, he shall make a detailed note of all factors relating to the accident, preserve evidence and record the statements of those who were near the accident spot. He shall also carry out a preliminary investigation as to the possible cause of accident and get full particulars of the injury or damage suffered and advise the Sr. Divisional Electrical Engineer of the details in writing. The treatment laid down for resuscitation after electric shock shall be carried out immediately if applicable. The treatment should be continued for at least two hours or more as there have been cases where patients, although apparently dead, have regained consciousness. 3. All electrical accidents occurring within Railway premises shall be reported to the Electrical Foreman/Chargeman in charge of the area and by him to the Sr. Divisional Electrical Engineer without delay, however slight the injury may be and even though the injured man is capable of performing his duties. 10502 Observance of Rules All accidents arising out of the use of electricity within the railway premises are required not only to be dealt with under the provisions of the ‘Rules for Reporting Accidents’ of the Zonal Railway but also according to the procedures under the Indian Electricity Act,. 1910, section 33 and Rule 44 A of I.E. Rules, 1967. Section 33 of I.E. Act 1910 reads as under: 1. If any accident occurs in connection with the generation, transmission, supply or use of energy in or in connection with any part of the electric supply lines or other works of any person and the accident results or is likely to have resulted in loss of human or animal life or in any injury to a human being or an animal, such person shall give notice of the occurrence and of any such loss or injury actually caused by the accident, in such form and within such time as may be prescribed, to the Electrical Inspector and to such other authorities as the appropriate Government may be general or special order, direct. 2. The appropriate Government may, if it things fit, require, any Electrical Inspector, or any other competent person appointed by it on his behalf, to inquire and report: a) as to the cause of any accident affecting the safety of the Public, which may have been occasioned by or in connection with, the generation, transmission, supply or use of energy, or b) as to the manner in, and extent to, which the provisions of this Act or any license or rules thereunder, so far as those provisions affect the safety or any person, have been complied with. 3. Every Electrical Inspector or other person holding any inquiry under sub-section (2) shall have all the powers of a Civil Court under the Code of Civil Procedure 1908, for the purpose of enforcing the attendance of witnesses and compelling the production of documents and material objects; and every person required by an Electrical Inspector or such other person as aforesaid to furnish any information shall be deemed to be legally bound to do so within the meaning of Section 176 of the Indian Penal Code. INDIAN RAILWAYS-AC TRACTION MANUAL-VOLUME1 10503 Electrical Inspector to Railway The Chief Electrical Engineer of each Railway is appointed to function as Electrical Inspector to the Central Government for the Railway vide Railway Board’s Notification No. 60/Elec/112/6 dt. 10th June 1961. All matters in regard to the functions of Electrical Inspector shall be referred to him. 10504 Reporting of Accidents The Electrical Foreman/Chargeman shall send in respect of every electrical accident a notice of the accident in writing to the Electrical Inspector viz., Chief Electrical Engineer, through the Sr.DEE/DEE. In case where the accident results in or is likely to have resulted in loss of human being or animal, intimation shall be given within 24 hours of the knowledge of the occurrence of the accident by express telegram to be confirmed by a post copy. The written report of the accident shall be sent in the form set out at Annexure ‘XIII’ of I.E Rules. All fatal and grievous hurt accidents shall also be immediately reported to the nearest Police Station. District Magistrate or Sub-Divisional Officer in charge of the Civil Jurisdiction and the body (in case of fatal accidents) shall not be moved until the Police Inquiry is completed. In the case of electrical accident occurring within workshop premises, the Factory Rules and Act will apply. In this instance the “Manager” of the workshop will send the detailed report on the forms prescribed in the Factory Rules to the Factory Inspector, in addition to CEE, CWE,DRM etc. 10505 Accident Inquiries Every electrical accident shall be inquired into by an officer and a report submitted to the Chief Electrical Engineer (functioning as the Electrical Inspector for the Railways) giving complete information within one week of the accident. The report should in particular cover the following points:- 1. A clear description of the locality and a sketch showing all the relevant details; 2. An analysis of the evidence recorded; 3. Findings as to the exact cause of the accident; 4. Fixing up of responsibility of staff negligence, if any, indicating whether the “Rules for Safe Working on Electrical Equipment” have been followed or not: 5. Recommendations for preventing such accidents in future : and 6. Any special features peculiar to the case. Until the official inquiry is conducted all material evidence should be preserved by the official in- charge of facilitate the inquiry. Where restoration of supply is likely to obliterate marks on the premises or in any other way destroy evidence which may be of use in an inquiry, the Senior Electrical Official who first arrives at the site should carefully make notes and sketches and preserve the evidence as far as possible, for production at the inquiry. 10506 Accident Registers and Annual Returns. Every Electrical Official in-charge shall maintain a register showing the particulars in regard to all electrical accidents taking place under his jurisdiction in the proforma below:- ---------------------------------------------------------------------------------------------------------------- Date Time Brief description Date & Time of Date accident of the accident issue of accident report submitted Telegram INDIAN RAILWAYS-AC TRACTION MANUAL-VOLUME I  He will also submit by 15th April of each year a statement of accidents during the previous financial year to Sr. DEE, who in turn will submit the statement for the entire division to the CEE for incorporation in the Electrical Inspectors Annual Report to CEA. 10507 First Aid A box containing first aid equipment shall be kept in each generating station or each sub-station and electrical work depot (except where adequate medical facilities exist for all the 24 hours of the day) close at hand for use when required. A periodical check shall be made of the contents and any deficiencies shall be reported to the Medical Department for replenishment. RESUSCITATION FROM ELECTRICAL SHOCK 10508 Instructions to be Displayed Instructions in English and the Regional language regarding the treatment of persons suffering from electric shock shall be exhibited in all inspection sheds, stabling depots, repair shops, stations, sub- stations etc. and it is the duty of every authorised official to make himself thoroughly familiar with such instructions, and to be able to render artificial respiration when necessary. Instructions regarding the methods of rendering artificial respiration have been given in paras 10509 and 10510. Electrical shocks are easily received but are as easily avoided if proper precautions are taken in maintaining and handling electrical equipment. 10509 Removal from Contact If the person is still in contact with the apparatus that has given him the shock, the rescuer should, if possible, stand on a dry wooden chair while removing the victim. Otherwise pull him free by using a dry coat, dry rope, coconut matting or stick, preferably standing on a rubber mat or any other dry mat handy. Never touch the man’s body with bare hands. Extinguish any sparks if the patient’s clothes are smouldering; ascertain if he is breathing and send for a Doctor. If apparently not breathing, proceed as described in para below. 10510 Artificial Respiration If there are any burns, avoid, if possible, so placing the patient as to bring pressure on the burns. It is preferable to operate as in the Diagrams A & B, Fig. 5.01, with the face downward. If badly burnt in front, turn to the second method shown later. First Method First Motion : Observe Diagram A – “Expiration”. Kneel over the patient, rest the hands flat in the small of his back, let your thumbs nearly touch, spread your fingers on each side over his lower ribs as in the first diagram. Now lean firmly but gently forward over the patient, exerting a steady pressure downwards, still following the first diagram. Second Motion : Observe Diagram B – “Inspiration”. Rock yourself gently backwards but do not remove your hands. Merely keep then in position for the next expiration pressure. Continue these two movements. The double movement should be gone through about fifteen times per minute. The object is to keep expanding INDIAN RAILWAYS-AC TRACTION MANUAL-VOLUME I and contracting the patient’s lungs so as to imitate slow breathing. If the operator himself breathes slowly, letting the air out as he presses forward, and drawing it in as he rocks backward, he will naturally arrive at the proper rate, and will understand the reason for the movements. Do not cease operations until natural breathing is re-established. It may take half an hour or even longer, to produce a desired effect. Second Method Should it be expedient to place the patient on his back , first loosen the clothes around the chest and stomach. Then placed a rolled-up coat, or other improvised pillow, beneath the shoulders so that the head falls backwards. The tongue should then be drawn forward. First Motion : The operatoe must kneel in the position shown by Diagram C. Grasp the patient just below the elbows and draw his arms over his head until horizontal, retaining them there for about two seconds. Second Motion : Next bring the patient’s arms down on each side of its chest and pressing inwards upon his arms so as to compress his chest as in Diagram D. Remain thus for two seconds, and then keep repeating the two motions at the same rate. INDIAN RAILWAYS- AC TRACTION MANUAL-VOLUME I  The lung-inflating effect in Diagram C is much assisted if the arms be swung outwards as they are lifted. If more than one person is present, the patient’s tongue should also be drawn out during each outward or lung-inflating stroke (Diagram C) and released during each inward or lung deflating stroke (Diagram D). In both case, be careful to avoid violent operations, as injury of the internal organs may result from excessive and sudden pressures. After recovery, burns if serious, should be treated with a proper oil dressing. Avoid exposing patient to cold. Administer no restoratives until the Doctor comes. Cold water may be given and smelling salts applied in moderation. Two methods of treatment for electric shock have been described above. It is the duty of every railway servant to be familiar with these methods of rendering artificial respiration. 10511 Typical Electrical Accidents Brief particulars of a few electrical accidents which have actually occurred are given below. A study of these particulars will help officers and staff in appreciating the importance of the various safety rules prescribed. 1. A khalasi of the Engineering Department, engaged in construction work, sustained severe burns when handling a long boiler tube under live OHE. The boiler tube accidentally touched the contact wire. This accident could have been prevented if proper supervision had been exercised and the Supervisor in- charge of the work had warned all his staff of the danger of electrocution if the OHE is accidentally contacted by poles, ladders, pipes or tools. Whenever there is even a remote possibility of any person coming within the danger zone of live 25 kV installations at sub-station, Switching stations or if any work has to be done within 2 m of live OHE, the supervisory official in-charge should invariably obtain permit to work after the lines are made dead and earthed before allowing staff to start work. 2. An electric fitter working on a locomotive stabled in a loco shed climbed on to the roof to examine the pantograph which was in the lowered position. The height of the contact wire on the stabling line was 5.5 m and the height from rail level of the pantograph in the lowered position was 3.66 m. The fitter was apparently under the impression that he could conveniently examine the lowered pantograph taking advantage of the clearance of nearly 2m. Unfortunately, while he was examining the lowered pantograph, the other pantograph of the locomotive was inadvertently raised by another employee thus energising the lowered pantograph also. There was also danger of the employee getting a shock if he had inadvertently stood up on the roof in the course of his work. This emphasizes that no one should ever get up on the locomotive roof when the locomotive is under a live OHE. A shut down should invariably be effected before climbing on to the roof of stabled locomotives. 3. Two work parties were required to work at an insulated overlap connected together by an interruptor. Shutdown was effected on both the elementary sections and the interruptor was also opened. One party earthed the OHE on one side of the insulated overlap and the supervisor of this party permitted his men to commence work on the insulated overlap without earthing the other portion of the OHE presuming that the other portion had been earthed by the other work party. This resulted in some of the workmen getting electric shock due to contact with the unearthed wires. This accident emphasizes the importance of the rules that (a) each party should protect itself by independent earths and (b) when work is to be done at an insulated overlap either both portions of OHE should be independently earthed or the electrical continuity between the two portions should be ensured by keeping isolators/interruptors closed. 4. A supervisor took power block for two elementary sections supported on a portal and overlooked the fact that the same portal supported the wires of a siding. Consequently a worker sent to work on the portal structure came into contact with the live OHE of the siding and sustained shock which resulted in his death. This serious accident could have been prevented if the supervisor had made himself thoroughly familiar with the details of OHE supported on the portal and had ensured that all the wires on the portal structure were made dead and earthed before permitting his men to commence work on the portal. INDIAN RAILWAYS-AC TRACTION MANUAL-VOLUMEI 5. An Electrical Chargeman (OHE Maintenance) received a fatal shock when he came into contact with OHE, which had been isolated but not earthed. On completion of work , he removed the earth and went down into the OHE Inspection Car to check up the time. Subsequently, he went up the OHE Inspection Car again and came into contact with OHE, which was not earthed though isolated. A slight drizzle earlier contributed to the severity of the shock as the Chargeman’s feet and the tower wagon platform were wet. Due to parallelism with the live OHE of an adjacent line, there was an appreciable induced voltage in the line, though it was isolated. This emphasizes the need for ensuring that the OHE is earthed in accordance with the rules prescribed before commencing work and during the whole time the work is in progress. 6. An Assistant Driver of a diesel locomotive of a Steel Works doing shunting work in an electrified yard close to the Steel Works received a severe shock when he went up on the roof of the locomotive. The warning notice regarding live OHE was not painted on the locomotive nor was the Assistant Driver properly instructed on the hazards of working in close proximity to live OHE. This emphasizes the need for painting the warning notice not only on the locomotives belonging to the Railway but also of private parties likely to work in electrified railway yards. Operating staff of private parties also should be educated in the safety rules prescribed. 7. A Linesman received a severe shock when working on an isolator. Before commencing the work one earth has been placed on each side of the isolator. However, during the course of the work, the isolator was opened when the Linesman received a shock. The possible cause is that one of the discharge rods was not making proper contact with the result that effect of induced voltage on that portion of the OHE caused the shock. This emphasizes the need for ensuring that when working on an isolator, either the isolator is kept jumpered or not opened at all during the course of the work , in addition to the precaution that an earth should be placed on each side of the isolator. 8) Supply from an auxiliary transformer has failed. An unskilled khalasi was sent by the fitter to check up and renew the high voltage fuses. The khalasi attempted to do this without getting a permit to work, accidentally came into contact with live 25kv wires and was electrocuted. This accident was a direct result of an unauthorized person not holding a certificate of competence being deputed to work on live equipment. 9) An electrical fitter was electrocuted while carring out repairs to a jumper connection to a transformer. He had isolated the transformer and climbed up the pole to repair the jumper. He had posted a helper near the circuit breaker with instructions that on receiving a signal from him, the helper should close the circuit breaker. The helper saw a person at a distance waving his hands and presuming that the signal is from the fitter, closed the circuit breaker. The accident was the result of adopting short circuit methods rather than the prescribed procedure for effecting shut down and issue of permit to work. Such short circuit methods are not permissible even if the intention is to speed up the work. The above cases would illustrate that a heavy responsibility rests with officers and senior supervisory officials to prevent possibilities of electrical accidents not only by insisting on strict compliance with rules and procedures laid down for safe working on electrical equipment, but also by giving wide publicity to the need for utmost precautions on the part of everyone when working in electrified sections. INDIAN RAILWAYS – AC TRACTION – VOLUME -I (56)