Upload
pillai-sreejith
View
2.449
Download
2
Embed Size (px)
DESCRIPTION
The presentation covers all the electrical safety issues, relvent national and international standards. The global electrical safety devices are also discussed in this presentation.
Citation preview
In this presentation……
Section IElectrical hazardsElectrical accidents – StatisticsHumans & ElectricityElectrical Safety Programme elements
Section IIGlobal Developments in Electrical Safety
Electrical Accidents-Statistics
• • 25% of all fires occur due to electricity (NFPA)
• 411 deaths from job related electrical accidents per year (NIOSH)
• Electrocution - the fifth leading cause of death (1982 - 1990) NIOSH
•About 12 deaths due to electrocution NCRB, (India)
•42 % of total fires occur due to electrical sources (Source -OISD)
• 8% deaths that occur in Indian factories are due to electricity
ELECTRICAL ACCIDENTS- 10 year Period, Chemical Industry
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 70Take 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 EMPInstall master control switches outside all
storesMaintain PFEs for electrical roomsConsider 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 interlocksDo not repair electrical components of
your machineProperly shut off machinery before
operationObey warning signs and follow safe
proceduresFollow 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
Present Status - ES-India
•ES Awareness is slowly growing
•Use of RCCBs in the rise, finer details are yet to be understood by many
•More ES workshops / seminars are conducted in India
•Statutory regulations are enforced strictly (Karnataka, Delhi - Use of RCCBs mandatory in residential buildings)
•Many industries are re-aligning their Electrical practices based on international standards (NFPA, IEEE, etc.)
Evolvement of ES Standards / organizations-United States
•NFPA - NEC (1897)
•NESC (1913), from IEEE
•NIOSH (Research example: development of voltage detector that will signal the person if he gets close to live power)-1970
• OSHA (1970)
•NFPA 70 E & B (1979) -approved by OSHA
•Electrical Trauma Centre, Chicago (1990)
•NESF(1994), by UL, NFPA, NEMA, CPSC
ES Products...
ES Auditing Techniques
• Electrical Risk Assessment using Semi-Quantitative Risk Ranking (SQRR) technique
•Emergency Lighting Risk Assessment
• Benchmarking against applicable standards:
•NFPA 780 Lightning Protection
•NFPA 70 M Electrical Preventive Maintenance
•NFPA 70 E Personal Safety from Electrical Safety
Electrical Risk Assessment (SQRR Technique)
Risk Ranking based on severity, probability
High Risk- Statutory Non-compliance, F&E hazards, Shock hazards, Risks that could result in immediate threat to life & property. Immediate correction
Medium Risk - Maintenance flaws,Operational issues-correction at the next available opportunity.
Low Risk - Mainly improvement measures, long term implementation
RCCB Tripping
How do we solve this problem in India ?
Bypass it !!!
ES related Information Indian Electricity Rule, 1956 (2000 rev.):(MoP, CEA web site,http://powermin.nic.in)
Lightning Protection Risk Assessment:www.furse.com
National Electrical Safety Foundation: www.nesf.org
Free safety Power Point presentations: http://siri.org/
Electrical Accidents: http://www.safteng.net: IEEE IAS ES WS –Delhi Dec. 2004
Standards & Codes
NFPA 70 E & B- E-Safety & MaintenanceNFPA 780- Lightning ProtectionAPI RP 2003- Static ElectricityAPI RP 500- HACOSHA 29 CFR- part 1910- Arc Flash NFPA 70- NEC IEEE 1584- Arc Flash ProtectionNFPA 77- Static ElectricityOSHA 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