Electrical Safety

Electrical Safety & Accident Prevention 1

Accidents An Accident is An unexpected, unplanned, undesired event or a sequence of a events. that occurs through a combination of causes which results in physical harm ( injury, disease, death) to individual, damage to property & interruption in completion of an activity or any combination of these effects. 2

The causes for occurrence of  Electrical Accidents 1) 2) 3) 4) 5) 6)

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Non observation of safe safety ty precautions Sub-standard method of construction of lines. Sub-standard materials utilized. Improper maintenance Improper authorization Ineffective Ineff ective supervision at various levels

Ineffective earthing 8) Unguarded live lines passing through close proximity of  telecom lines & densely populated areas 9) Ignorance of rules & regulations 10) Negligence 11) Overconfidence 12) Carelessness 3

Remedial measures suggested 1) 2) 3) 4) 5) 6) 7) 8)

Training to line staff  Providing ample quantity of safety equipments Issuing instruction of “safety “safety of working on line” to line staff & making them aware of importance of following the same Providing sufficient quantity quantity of maintenance material material to unit offices offices Displaying “single “single line diagrams of line feeders network” on walls of S/S (including latest changes in feeding if any) Replacement of deteriorated poor earthing Carrying out pre monsoon/ post monsoon maintenance well in advance Compelling line staff staff & developing habit habit in them to discharge lines at work spot before climbing on it In other words not to work on lines without discharging it (even if permit is taken, load shedding persists are line is really dead) because they should be aware that line may get charged due to any of the reason such as fault in switch gear/ line, someone may charge the line by oversight, back feeding, feeding, induction etc. & the discharge rod should remain installed on both sides of  work spot till the completion of work. ALM/LM or any other supervisor should restrict LH to work on line without discharging d ischarging it. Should insist to keep line discharged till completion of work. 4

Remedial measures suggested 9) Providing anti climbing devices, danger boards to poles/ structures etc. 10) Restricting public to construct building below or in vicinity of lines 11) Check on theft of energy. Unauthorized substandard extension 12) Electricity is invisible & do not speak; we should be alert about its existence. Confirm by discharge rods before touching it. 5

Safety Slogans :1.Be 1. Be safety safety minded 2. No holiday for safety 3. If it seems risky, don’t do it. 4. Always be alert, Avoid Avoid accidents. 5. Safety requires careful working. 6. Time is important but safety is far more important.

7. “Always be careful” is the ABC of safety. 6

8. Follow the procedure of safety. 9. Little care makes mishaps rare. 10. Do not think it is safe make it sure. 11. Accident begin where safety ends. 12. Guard against risk and work for safety. 13. Eliminate all shortcuts, while on duty 14. Where vigilance ends accident begin.

15. Don’t trust luck, trust to safety.

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16. If a job is too big for you, get help don’t get hurt. 17. Never feel sure that you are safe. 18. Jokes begun in fun can end in tragedy. 19. Life is short and precious don’t make it shorter by carelessness. 20. Do not take chances with your life follow safety rules meticulously  Above slogans are the key key of safety, safety, hence while working, these slogans shall be kept in mind.

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Safety Norms in an EHV S/Stn. 1) Presently there is no codified codified norms prescribed for safety in EHV S/Stn. however some norms are in circular or letter form. 2) Followin Following g are the proposed proposed safety safety norms based based on 37 years years experience.

i) In Ex Extr tra a ord ordin inar ary y co cond ndit itio ion n a) Like earth quak quake, e, land land slide slide & sinki sinking ng of land land,, in such such conditions precaution to be taken in adopting safe building technology and precaution for power transformer installation installation like providing providing temporary temporary breaks breaks to transformer wheels wheels & soil treatment etc. b) Storm Storms, s, Floods Floods and and other other natural natural calam calamites ites c) Terror errorist ist attack attack & War War conditio condition n d) Publ Public ic and and Staf Stafff agita agitation tion 9

ii) In ordinary condition a) EHV S/Stn is a prohib prohibited ited area. b) The area shall be well fenced fenced and properly locked locked and entry of  outside person and animal prohibited for any purpose. c) Prop Proper er watch watch and ward shal shalll be kept kept.. d) The S/Stn. S/Stn. shall shall be construct constructed ed maintain maintained ed and operated operated as per I.E. act rules and other statutory acts and regulations applicable. e) Earthing is a heart of electrici electricity ty to avoid avoid any damage to human life and equipment and shall be provided as per I.S. 3043 and maintained so that touch potential and step potential and earth fault loop impedance remains within permissible limit. 10

f) All structures, equipment, shall be installed, maintained and operated as per I.E. act and concerned rule, methods of  constructions and practices according to it and all equipments and structures shall be as per concerned I.S. standard and due attention shall be given to the maintenance schedule prepared by department for each item also the maintenance Recommendations of the manufacture shall be given due weightage to avoid equipment failure, fires and break downs. Some important items are given below. 1. Precaution for power T/F replacement replacement,, installation and handling. 2. Regarding battery. 3. Bursting of CT, CT, PT and LA 4. Crushed Stone and grown up grass in switch yard. 5. Monkey troubles.

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g) Fires :- Causes of Fires 1. Sparking in S/Stn. due to loose contact. 2. Fire due to Transform Transformer er failure CT PT & catching of fire by oil mainly due to failure of bushings. 3. Precaution to be taken in this regard. 4. Dry grass in S/Stn. area. 5. Cable faults. 6. Burning of Control cable due to increase in ground potential rise due to tripping. 7. Flash over in Indoor panels & various causes. 12

h) Precautionary measures. 1. Every power T/F shall be provided with fire protection scheme and oils sockpit shall be provided with proper drainage arrangement 2. Providing and installing fire fighting equipment in complete S/Stn. area as per the norms provided by fire officer of the department and staff shall be well trained in handling fire situation and regular drill shall be taken every year the fire protection equipment equipment shall be tested and refilling done. 3. Fire alarm and siren shall be provided. 4. Safety instruction shall be display in this regard at important locations. I) To carry out safety audit regularly  j) Storing of material material and house house kipping of S/Stn. S/Stn. shall be very very clean and suitable for free moments and gating required things very easily whenever required. k) Illumination :- The illumination intensity shall be measured and monitored regularly

l) All precautions shall be taken to avoid theft. m) Rains and control room leakages and there effects and other  seasonal precautions. n) Communication o) In every S/Stn. logging of every instance shall be there and event recorder installed.

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Safety T & P • Earthing & Discharge Rods. • Ladders, safety belts. • Operating Rods • Hand gloves – gloves – insulated. • Insulated pliers, Neon tester testers. s. • Insulated Platform, rubber mats 15

Discharge Rods • 5 to 6 m long • Earthing wire to be connected to an effective earth first & then the rod to be hooked to conductor. • While removing, reverse sequence to be followed.

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Insulated hand gloves • To be invariably used where accidental contact of  operating person with live parts is likely i.e. when (i) operating G.O.D., D.O. sets (ii) Opening Opening/closing /closing isolator isolators. s. (iii) Working near live lines • Should withstand 10 KV for one minute. • Gloves with leakage current of more than 10 milliamps to be rejected. 17

Maintenance of hand gloves • Should be carried in canv canvas/leather as/leather bag. • Should be stored in dry container with no sharp edges. If stored & not used for more than six months testing to be done • Not be exposed to extreme heat or cold. • Oil is the enemy of gloves. • Not to be soiled with oil, tar, paint etc. • Should be free from cuts, scratches, holes. 18

The points which are neglected for accidents likely to take place 1) In this regard the Indian electricity rules : 1956 rule 42 says.. says The owners of all circuits and apparatus shall so arrange them that there shall be no danger of any part thereof  becoming accidentally charged to any voltage beyond the limits by voltage for which they are intended.

2) Responsibility of Individual Employees:The responsibility of Individuals is to act so as to provided. i) Safety to Self. ii) Safety to fellow employees. iii) Protection to the public. iv) Protection to the equipment.

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3) Responsibility of Supervisors :Supervisors have the definite responsibility of ensuring the Supervisors following i) Safe working conditions. ii) Necessary protective equipment and its use. iii) Properly maintained tools and equipment. iv) Properly planned work performed in a safe manner. v) Application of the general & special safety instructions by their workmen. vi) Assignment of employees to jobs which they are capable of  doing safety safety.. vii) Immediate steps to correct any violation of safety rules observed or reported to them.

4) Each Supervisor shall make certain that his men understand the following :i) Work to be done. ii) Hazards that may be encountered. iii) Proper procedure for doing the work safety.

5) Frequent periodic inspections of construction, operation and maintenance of equipments, materials, work areas, conditions and methods should be made by supervisors as a part of their routine duty. Such inspections are essential to prevent fires and Accidents. 6) The rout cause of types of accident likely to take place in EHV S/S and on EHV lines in negligence to the above 21 point.

Types of accidents. A) EH EHV V S/Stn. S/Stn. ::i) Fla Flash sh over over dur during ing wor worki king ng on on indo indoor or pane panels. ls. ii) Improper Improper use use of discha discharge rge rods and wrong wrong operati operations ons and and failure of tools. iii) Bursting of CT PT and falling falling hot oil on superviso supervisorr or person. person. iv) Falling from height height due to non use use of safety devices. devices. v) Acc Accid ident ental al char chargin ging g vi) Bursting of LA and injuring the persons in switch switch yard. vii) Due to non checking of soil for unloading power T/F and careless working viii) Due to fires in S/Stn.

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B) Lines :i) Im Imp pro rop per clear aran anc ces ii) Work orking ing on wro wrong ng circ circui uitt iii) not following safety instructions iv) fail failure ure of tool tools s v) Whi While le exca excavati vation on due due to blas blasting ting vi) during line construction construction such as tower errection errection stringing and crossing of roads etc. vii) During transport.

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Authorisation • For being eligible to apply for & obtain permit, the employee must be `authorized’ `authorized’ by the `competent’ authority. `competent ’ person (E.E. or in charge • Person issuing permit is `competent’ operator)

• Person receiving permit is `authorized’ person. 24

Authorisation Under Section 3, Sub-rule (3) of I.E. Rules 1956.

• “No person shall be deemed to be `authorized’ unless his name has been entered in `authorization list’ list ’ maintained at the office of  the person authorizing him.” him.” • Purpose of authorization to be mentioned. Entry in the list to be attested by `authorizing’ & authorized persons. 25

Authorisation List  • To be produced before Electrical Inspector whenever required. • Inspector may amend / cancel authorisation. • To be exhibited in Sub-stations/Distribution Centres. • Will clearly state the area of authorisation (I.e. name of S/S, names of lines etc.) 26

Authorisation List  • Will clearly state the area of authorization (i.e. name of S/S, names of lines etc.) • To be maintained in the office of S.E. (O&M) E.E. (O&M) of  area. • To include names of testing staff given by E. E. (Testing)

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Authorization • As per I.E. rules 1956, section 36, sub section (2) No person shall work on any electric line or apparatus and no person shall assist such person unless authorized to carry out that work. 28

Line clear Permit  • Authorized person should apply for issue of permit to competent person on the back side of O/C of permit. • Issuer of permit to cut off juice to the equipment/line, discharge and earth it before issue of permit.

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Permit taken on phone • `Taker’ of permit to clearly state his name, designation, equipment/line on which permit needed and purpose. • `Issuer’ to note down the above in a specially maintained permit book, give code word & number & record it. • `Taker’ to repeat the above and give his code word & number to issuer. 30

Permit on phone • While returning the permit, the `taker’ to state the code word/number given by `issuer’, confirm removal of earth and men from the line. • Permit taken in person can be returned on phone. • Duplicate copy of permit to be sent by post by `issuer’ to `taker’ of permit subsequently after cancelling it. 31

Self Permit  • Here, `issuer’ & taker of permit is one & the same. (when only one authorized person is available). • He should isolate, discharge, earth the equipment/line, hang `men working on line, Do not charge’ board on switch, take written permit after clear logging & then work. 32

Logging of Permit  • All operations done before & after issue of  permit to be logged. Also those done by remote end to be logged. • Issuer of permit may change after end of shift. • Outgoing operator to clearly inform in writing & orally about pending permits. • Though `issuer’ may change, `taker’ should himself return permit.

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Precautions by Issuer • Limits of line clear permit area to be clearly mentioned in the permit and told orally to the Receiver of permit e.g. :`Isolator is live on the other side’ in the feeder bay bay.. 34

Precautions by Issuer H.T. feeder – feeder – Radial • Open controlling circuit breaker & open isolators on both sides. • Close earth switch if isolator `with E.B.’ E.B.’ provided & mention in the permit. • If earth switch non-existent, provide discharge & earthing rods.

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Precautions by Issuer H.T. feeder fed from both sides • Obtain permit from the other end. • Inform earthing position of  sending end & note down position at other end. 36

Precautions by Permit holder on H.T. lines. • Discharge & earth earth each conductor conductor.. • Retain earthing in firm condition on either side of the work location. 37

Precautions by Permit holder On one of the circuits when other circuit is live on H.T. D/C line.

• Only works of minor nature such as renewing insulator binding etc. to be done. • Safety belt, rope to be used. • Minimum distance of 1050 mm to be maintained from live circuit. • Work strictly under personal supervision of A.E. 38

Earthing – definition • Connecting the portion of an equipment, support structure, enclosure associated with an electric system to General mass of  earth. 39

Purpose of earthing • Safety of human beings / animals coming in or likely to come in contact with electrical installation.

• Proper/desired operation of  `System’ 40

Safety earthing • Metal enclosures of C.B.s, C.T.s, PTs, tanks of Power transformers, support towers, poles, stays, operating handles of isolators, A. B. Switches, feeder pillars etc. which are desired to be at earth potential, are earthed .

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System Earthing • Neutrals of star connected windings of power transformers solidly connected to earth for speedy isolation of earth fault & avoiding `oscillating neutral’ neutral’.. • Thus, lower phase voltage in loaded phase and high voltage in lightly loaded phases avoided. • Otherwise voltage of healthy phases of  transformers transf ormers rise leading to insulation failur failure. e. 42

Safe body current  From Biological research, human body can toler tolerate ate -10 milliamps of sustained body current -100 milliamps of short-time body current for less than one second.

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Accident Prevention 1. Ever Every y accident accident can can be avoided avoided if if earthing earthing is perfect perfect,, safety safety devices used and maintained as per Indian standard and I.E. rules and safety instruction followed given I.E. rules and various Indian Standard during working. 2.

construct cons truction ion main maintena tenance nce and opera operation tion carri carried ed out as per  I.E. rules, methods of construction and concerned Indian standards and all safety slogans followed and workers and supervisor understand there responsibility and public follow directives as per Indian electricity rules 1956 rule 82

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Reporting & Investigation of Electrical

 Ac  A ccidents • All out efforts are usually made to ensure that no electrical accidents happened, inspite of best efforts. • It is seen that a few few accidents accidents do happen here & there including in the consumers’ premises. • In such situations, a definite procedure for reporting such accidents has been laid down in the electricity act 2003 & IE Rules 1956. 45

 Section 161( Notice of accidents &

enquires) of electricity act 2003.

occ urring in • This clause provide for giving notice/intimation of accidents occurring connection with Generation, Transmission, Transmission, Distribution or use of  electricity on lines & electrical plant, to the electrical inspector

• The electrical inspector or any other officer appointed in this behalf has the powers to enquire & report as to the cause& the manner & extent to which safety povisions have been complied with. p owerss of civil court under • Under this clause, the electrical inspector has power the code of civil procedure, 1908 for for the purpose of enforcing the attendance of withness & compelling the production of documents & material objects. 46

IE Rule 44 A • If any accidents occurs in connection with the generation, transmission, transmission, supply or use of energy in or in connection with, any part of the electric supply lines or other works of any person & the accidents results in or is likely to have have resulted in the loss of human or animal life or any injury to a human being or an animal. • such person or any authorized person of the State Electric Board/ supplier, supplier, not below the rank of the Junior Engineer or equivalent shall sent to the inspector a telegraphic report report within 24 hours of the knowledge of  the occurrence of the fatal accident. o ut in annexure XIII • And a written report in the form set out within 48 hrs. of the knowledge k nowledge of occurrence of fatal & 47 all other accidents.

• Where practicable a telephonic message should also be given to the inspector immediately after the accidents come to the knowledge of the authorized author ized officer of the State Electric Board/ Supplier or other person concerned. inspector, such accidents • After reporting to the electrical inspector, are investigated by the executive engineer/ superintending engineer in detail to decide the exact cause of the accident, accident, to pay compensation to the victims as per the law & to to fix up responsibility responsibility for the accident & undertake remedial measures to avoide recurrence. 48

Annexure XIII • This is a prescribed form for reporting electrical accidents to the electrical inspector. • A copy of this form should also be sent to the concerned police station & district magistrate magistrate of the area.

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