presented by:
Pillai Sreejith

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Electrical Safety
Electrical Safety Global Developments
Section I
 Electrical hazards
 Electrical accidents – Statistics
 Humans & Electricity
 Electrical Safety Programme elements
Section II
 Global Developments in Electrical Safety
 Electrical Near-Misses & Accidents- Major Causes
 Working on live equipment w/o authorization or PPE
 Wiring mistakes coupled with failure of safe-energy conditions
 Leaving unsafe conditions
 Electricity and People
 A person usually offers a lesser resistance
for the electricity
 The person forms a completed circuit when touching the ground
 Electricity always tries to travel to ground
ELECTRICAL FIRES ….
 ELECTRICAL FAULTS (Contd.)
– STATIC DISCHARGES
– LIGHTNING
– USING ORDINARY ELECTRICAL EQUIPMENT IN HAZARDOUS AREAS
– Earthing
 Most electrical equipment is designed with a earthing system
 Earth all equipment with metallic body (TVs?)
 Double & Single earthing- differentiation?
 Carry out ER tests annually as per NFPA 70
 Take action on high ER values
 Identify all earth pits, maintain a Earth Pit lay out
 Earth Leakage Circuit Breakers
 ELCBs reduce the likelihood of fatal shocks
 Detect small amount of leakage current and automatically switch off the power
 Can be used with extension cords and portable tools
 Fuses and circuit breakers protect equipment, not people
 Use the right sensitivity ELCBs (30, 100, 300 mA)
Static Electricity
 Created when materials rub together
 Can cause shocks or even minor skin burns
 Can damage sensitive electronic equipment
 Reduced or prevented by:
– Proper grounding
– Anti-Static rubber matting
– Bonding & earthing of equipment, pipelines
Electrical Fire Protection
 Use Linear Heat Sensing cables in cable cellars along with smoke detectors
 Consider all major electrical fires in EMP
 Install master control switches outside all stores
 Maintain PFEs for electrical rooms
 Consider local flooding systems for critical panels/ switchgear panels
Case Study
 An electrician received a shock while trying to replace a tube light ballast in live power condition.
 He touched a live conductor. He was not wearing rubber gloves. Current entered his right hand through his little finger and exited through his left hand.
Post Accident Correction:
– Working on live circuits not permitted
– LOTO to be strictly enforced
 Equipment Operators
 Never tamper with electrical interlocks
 Do not repair electrical components of
your machine
 Properly shut off machinery before operation
 Obey warning signs and follow safe procedures
 Follow PTW procedures strictly
 Electrical Preventive Maintenance
 Identification of critical Electrical Equipment
 Emergency lighting
 Fire Alarm System
 Protection Supply DC System
 UPS System, Battery Banks
 Electrical Maintenance Procedures to be aligned with NFPA 70 B
 Planning for EPM
 Personal Safety
 Equipment Failure
 Production Economics
 Electrical Preventive Maintenance
 Implement EPM without slippage
 Carry out all tests (ER, IR, transformer oil, DGA, LP system, transformer protective devices- simulation, FA system for electrical rooms, etc.)
 Adopt NFPA 70 E / B for electrical maintenance
 Adopt Risk Based maintenance
 Use predictive maintenance tools (hotspot detector, Ultrasonic detectors, Thermography)
 ‘All electrical accidents are preceded by rise in temperature & sound’
ELECTRICAL SAFETY AUDIT
 A systematic approach to critically analyze the existing Electrical Procedures and Practices from safety point of view
 Global Developments in Electrical Safety
 RCCB Tripping
How do we solve this problem in India ?
 ES related Information
 Indian Electricity Rule, 1956 (2000 rev.):
(MoP, CEA web site,http://powermin.nic.in)
 Lightning Protection Risk Assessment:furse.com
 National Electrical Safety Foundation: nesf.org
 Free safety Power Point presentations: http://siri
 Electrical Accidents: http://safteng.net:
 IEEE IAS ES WS –Delhi Dec. 2004
Standards & Codes
 NFPA 70 E & B- E-Safety & Maintenance
 NFPA 780- Lightning Protection
 API RP 2003- Static Electricity
 API RP 500- HAC
 OSHA 29 CFR- part 1910- Arc Flash
 NFPA 70- NEC
 IEEE 1584- Arc Flash Protection
 NFPA 77- Static Electricity
 OSHA CFR 1926-Personnel Electrical Safety
Summary
 Electricity will try to reach ground even if it means going through a person
 Earthing has an important role in ES
 Always inspect power tools and cords and do not use them if damaged
 Do not attempt to repair electrical equipment unless trained and qualified
 Understand effects of Lightning- it could save your life!
 Major fires, explosions occurred due to ESD , lightning in flammable atmospheres