Electrical Safety ..ppt for construction

electrical safety for construction site staff

1. 96 Hours Training– Mumbai
Metro Line 4
Project: AFCONS INFRA
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2. SAFETY PLEDGE
SAFETY PLEDGE
I solemnly affirm that I will do everything possible for the
prevention of accidents , occupational diseases and
protection of the environment in the interest of self, my
family, my community, my organisation and the nation at
large
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3. MMRC OHS&E Policy Statement of
Intent
Mumbai Metro Rail Corporation consider that health, safety and
environmental is of equal importance in comparison to any other
aspect of business management and as
such is committed to promoting high standards of safety, health,
environment and welfare on all of their sites and premises. To achieve
this Mumbai Metro Rail Corporation shall:
 Constantly work towards improving the safety culture at all levels.
 Ensure compliance with all relevant legal duties in respect of health
and safety at work legislation.
 Provide adequate resources for planning and controlling working
conditions and safe systems of work.
 Work with our Contractors and suppliers to improve their safety
performance, by Measuring and monitoring their performance.

4. MMRC Line – 4
Employer Requirement on safety
• General Introduction
• It is the objective of MMRC to ensure that the contract is completed on
Time,
• Within budget and to confirming standards of Health And Safety.
• Each contractor shall develop his own contract specific Site Safety Plan,
which will represent his approach to the management of safety on his
work, sites under the contractor with MMRC.
• The contractor is fully responsible for the safety of he works. His
personnel, sub-contractor personnel, the public and all persons directly or
indirectly associated with the works or on or in the vicinity of sites.
•Policy objective.
• 1) Every contract should aim at zero fatal accidents.
•2) Every contract should aim at zero dangerous occurrence
•3) Every contract should aim at an accident frequency rate (AFR) of less
than 0.5 per 1000,000 hours worked in contract.

5. SHE management system requirements
General requirement
•The Contractor shall define and document the scope of its
Occupational Safety Health and Environmental (OHS&E) management
system to meet legal requirements and the requirements of Mumbai
Metro Rail Corporation as stated within this document.
• The Contractor’s OHS&E management system shall determine how
the organisation shall document, implement, maintain and continually
improve upon performance in accordance with the requirements of
the International OHSAS Standard to which the Employer is
committed.

6. Responsibilities and performance
requirements for Safety, Health and the
Environment are summarised as follows
•All Contractors, employees, sub-Contractors, consultants, suppliers
and visitors have a duty to play an active role in achieving our
objectives through compliance with their legal obligations and this
Safety Policy.
• Participation and consultation are vital aspects of this Policy and to
the achievement of our objectives. Contractors and Staff are
encouraged and expected to :
•Discuss safety, health and welfare matters with their managers,
and company Safety, Health & Environmental Representatives who
will offer or obtain further expert advice, where necessary.
•Co-operate at all times; contribute good ideas and improvements;
report defects and short falls.

7. Occupational safety and health Objective
Consistent with the OSH policy and based on the initial or
subsequent reviews, measurable OSH objectives should be
established, which are:
(a) specific to the organization, and appropriate to and
according to its size and nature of activity.
(b) consistent with the relevant and applicable national laws
and regulations, and the technical and business obligations of
the organization with regard to OSH.
(c) focused towards continually improving workers’ OSH
protection to achieve the best OSH performance.
(d) realistic and achievable.
(e) documented, and communicated to all relevant functions
and levels of the organization.
(f) periodically evaluated and if necessary updated.

8. Legal and other requirement
•Motor vehicles act, 1948,
• Motor vehicle Act as amended in 1994, The central motor vehicle Rules, 1989.
• Indian road congress Code IRC:SP:55-2001 ‘Guidelines on safety in road
construction zones.
• The petroleum Act, 1934 and Rules 1976
•Indian electricity act 2003 and rules 1956
• National building code, 2005
•Factories act 1948
•Gas cylinder Rules, 2003
•Indian Explosive Act. 1884, Along with the explosives substance Act 1908 and the
explosive Rules 1983
• The ( Indian) Boilers Act, 1923
•The public Liability insurance Act 1991 and Rules 1991
•Minimum Wages Act, 1948 and Rules 1950
•Contract Labor Act, 1970 and Rules 1971

9. Legal and other requirement
•Air ( Prevention And Control of Pollution) Act 1981
• Water ( Prevention and Controls of Pollution) Act, 1974
• The Noise Pollution ( Regulation & Control ) Rules, 2000
• Notification on Control of Noise from Diesel Generator (DG) sets, 2002
• Recycled Plastic usage Rules 1998
•Child Labor ( Prohibitions and Regulations ) Act, 1986 and Rules 1950
• Environment Protection Act, 1986 And Rules 1986
•Notification, Central ground Water Board, Act January 1997
• Manufacture, Storage & Import of hazardous Chemicals Rules, 1989
• The Hazardous Waste ( Management & Handling ) Rules, 1989
• Batteries ( Management And Handling) Rules
• Fly Ash utilization notification, Sept 1999 as amended I August 2003
• Workmen Compensation Act, 1923 along allied Rules.

10. Reference
•MMRC Line 5 - EMPLOYER’S REQUIREMENTS OHS& E- Sec 4.3.2.2 (i) Indian
Electricity Act 2003 and Rules 1956
•MMRC Line 5 –OHS& E Manual Safety & Health – Sec 20.1.5 Temporary
Electrical Site installations
•MMRC Line 5 –OHS& E Manual Safety & Health –Sec 19.2 (19.2.5) Entry
Procedure
•MBCWR 2007 –Rule No 158 Breathing Apparatus
•BS OHSAS 18001:2007, Occupational health and safety management
systems Requirements
•BS OHSAS 18002, Occupational health and safety management systems –
Guidelines for the implementation of BS OHSAS 18001
•International Labour Organization: 2001, Guidelines on occupational health
and safety management systems — ILO-OSH 2001
•Health & Safety Guidance (HSG) Health and Safety Executive publications
United Kingdom

12. Fundamentals of Electricity Fundamentals of Electricity
• Electrical Electrical currentcurrent is the flow of electrons through a is the flow of electrons through a
conductor.conductor.
•A A conductorconductor is a material that allows electrons to is a material that allows electrons to
flow through it.flow through it.
•An An insulatorinsulator resists the flow of electrons.resists the flow of electrons.
•ResistanceResistance opposes electron flow opposes electron flow

13. Current Flows in a Current Flows in a
Loop or Circuit Loop or Circuit
• Circuits are AC (alternating current) or DC (direct current).Circuits are AC (alternating current) or DC (direct current).
•Current is usually AC.Current is usually AC.
•AC current has five parts:AC current has five parts:
(1) Electrical source(1) Electrical source
(2) HOT wire to the tool.(2) HOT wire to the tool.
(3) The tool itself(3) The tool itself
(4) NEUTRAL wire returns(4) NEUTRAL wire returns
electricity from the toolelectricity from the tool
(5) GROUND (5) GROUND

14. Electric activities at work shop
Distribution Panels,
Electrical equipments installation
Electrical Cable
Use of Power portable equipments
 Electrical material handling

15. Electrical hazards/Injuries
There are two main types of electric harms:
 Direct:-
 Electrocution may lead to death
 Electrical shock
 Burns
 Fire and explosion
 Indirect:-
 Falls

16. Hazards of Electricity Hazards of Electricity
•Shock – Most common and can cause electrocution or muscle – Most common and can cause electrocution or muscle
contraction leading to secondary injury which includes fallscontraction leading to secondary injury which includes falls
•Fires – Enough heat or sparks can ignite combustible materials – Enough heat or sparks can ignite combustible materials
•Explosions – Electrical spark can ignite vapors in the air – Electrical spark can ignite vapors in the air
•Arc Flash - can cause burns ranging can cause burns ranging
from 14,000 degrees f. to 35,000 degrees ffrom 14,000 degrees f. to 35,000 degrees f
•Arc Arc Blast – In a short circuit event copperIn a short circuit event copper
can expand 67,000 times. The expansion can expand 67,000 times. The expansion
causes a pressure wave. Air also expandscauses a pressure wave. Air also expands
adding to the pressure waveadding to the pressure wave

17. Electrical Accidents Electrical Accidents
• Leading Causes of Electrical Accidents:Leading Causes of Electrical Accidents:
–Drilling and cutting through cablesDrilling and cutting through cables
–Using defective tools, cables and equipmentUsing defective tools, cables and equipment
–Failure to maintain clearance distance of 10 feetFailure to maintain clearance distance of 10 feet
–Failure to de-energize circuits and follow Lockout/Tagout Failure to de-energize circuits and follow Lockout/Tagout
proceduresprocedures
–Failure to guard live parts from accidental worker contactFailure to guard live parts from accidental worker contact
–Unqualified employees working with electricityUnqualified employees working with electricity
–Improper installation/use of temporary electrical systems and Improper installation/use of temporary electrical systems and
equipmentequipment
–By-passing electrical protective devicesBy-passing electrical protective devices
–Not using GFCI (ground fault circuit interrupters) devicesNot using GFCI (ground fault circuit interrupters) devices
–Missing ground prongs on extension cordsMissing ground prongs on extension cords

18. Shocks Occur in Shocks Occur in
Three WaysThree Ways
•Contact with both conductorsContact with both conductors
•Contact with one conductor and groundContact with one conductor and ground
•With a tool: contact with “hot” metal part and With a tool: contact with “hot” metal part and
ground (1), (2) & (3)ground (1), (2) & (3)

19. Severity of the ShockSeverity of the Shock
•Severity of the Shock depends on:Severity of the Shock depends on:
–Amount of current Amount of current
•Determined by voltage and Determined by voltage and
resistance to flowresistance to flow
–Path through the bodyPath through the body
–Duration of flow through the bodyDuration of flow through the body
–Other factors such as general health and individual Other factors such as general health and individual
differences.differences.

20. Effects of Current FlowEffects of Current Flow
•More than 3 milliamps (ma): More than 3 milliamps (ma): painful shockpainful shock
•More than 10 ma: More than 10 ma: muscle contractionmuscle contraction
•More than 20 ma: More than 20 ma: considered severe shock considered severe shock
•More than 30 ma: More than 30 ma: lung paralysis lung paralysis - usually temporary- usually temporary
•More than 50 ma: More than 50 ma: possible ventricular fibrillationpossible ventricular fibrillation
(usually fatal)(usually fatal)
•100 ma to 4 amps: 100 ma to 4 amps: certain ventricular fibrillation certain ventricular fibrillation
(fatal)(fatal)
•Over 4 amps: Over 4 amps: heart paralysis; severe burns heart paralysis; severe burns

21. Effects of Current FlowEffects of Current Flow

22. Burns
Most common shock-related injury
Occurs when you touch electrical wiring or
equipment that is improperly used or
maintained
Typically occurs on hands
Very serious injury that needs immediate
attention

23. Controlling Electrical HazardsControlling Electrical Hazards
•Employers must follow the Electrical StandardsEmployers must follow the Electrical Standards
•Electrical installationElectrical installation
•Four proactive methods:Four proactive methods:
–Electrical IsolationElectrical Isolation
–Equipment GroundingEquipment Grounding
–Circuit InterruptionCircuit Interruption
–Safe Work PracticesSafe Work Practices

24. Electrical Isolation Electrical Isolation
•We can be safe by keeping electricity away from We can be safe by keeping electricity away from
us. We can:us. We can:
–InsulateInsulate the conductors.the conductors.
•Example: The insulation on extension cords.Example: The insulation on extension cords.
–ElevateElevate the conductors.the conductors.
•Example: Overhead powerlines.Example: Overhead powerlines.
–Guard Guard the conductors by enclosing them.the conductors by enclosing them.
•Example: Receptacle covers, boxes, & conduitExample: Receptacle covers, boxes, & conduit..

25. Insulating the Conductors Insulating the Conductors
•The first way to safeguard workers from electrically The first way to safeguard workers from electrically
energized wires is through energized wires is through insulationinsulation..
•Rubber and plastic is put on wires to prevent shock, Rubber and plastic is put on wires to prevent shock,
fires, short circuits and for strain relief.fires, short circuits and for strain relief.
•It is always necessary to check the insulation on It is always necessary to check the insulation on
equipment and cords before plugging them in.equipment and cords before plugging them in.
•Remember, even the smallest defect will allow Remember, even the smallest defect will allow
leakage!leakage!

26. Defective Extension CordsDefective Extension Cords

27. Elevating the ConductorsElevating the Conductors
•The second way to safeguard workers from The second way to safeguard workers from
electrically energized wires is by electrically energized wires is by elevatingelevating
them.them.
•Wires are often elevated by the power Wires are often elevated by the power
company.company.
•It is always necessary to It is always necessary to check the location check the location
of overhead lines before you begin work of overhead lines before you begin work
each day.each day.
•Remember, never allow yourself, your Remember, never allow yourself, your
tools, or the materials you are working with tools, or the materials you are working with
to be within to be within 10 feet10 feet of energized lines!of energized lines!

28. Guarding the ConductorsGuarding the Conductors
•The third way to safeguard workers from The third way to safeguard workers from
electrically energized wires is by electrically energized wires is by guardingguarding
them.them.
•Covers, boxes, and enclosures are often Covers, boxes, and enclosures are often
put around conductors to prevent worker put around conductors to prevent worker
contact.contact.
•It is always necessary to check that It is always necessary to check that
electrical boxes and panels are covered electrical boxes and panels are covered
and free from missing “knock-outs”. and free from missing “knock-outs”.
•Remember, electric equipment operating Remember, electric equipment operating
at 50 volts or more must be guarded!at 50 volts or more must be guarded!

29. Guarding the ConductorsGuarding the Conductors

30. Current flows through the body from the entrance point,
until finally exiting where the body is closest to the ground.

32. AVOID THE FOLLOWING UNSAFE ACTS

Worker’s attitude such as working without appropriate
PPEs.
Improper working method
Wearing of metal objects such as watches, necklaces &
rings.
 Working in wet and/or damp locations

33. AVOID THE FOLLOWING UNSAFE ACTS

34. AVOID THE FOLLOWING UNSAFE CONDITION OR
ACTS

35. AVOID THE FOLLOWING UNSAFE
ACTS

Failure to de-energize, lockout and tag out
hazards during maintenance, repair or
inspections of fuse box
Use of defective and unsafe tools
Use of tools or equipment too close to
energized parts

36. Double Insulated
Panels/Tools

37. What equipment can cause electrical accidents?
Damaged insulation of electrical wirings
Short Circuit
Overloading
Improper grounding

38. HAZARDOUS ENVIRONMENT

Flammable vapors, liquids and gases
 Combustible dusts
 Corrosive atmosphere
 Explosive environments

39. ELECTRICAL HAZARDS TO WATCH OUT FOR
Loose electrical connections
Non-waterproof cords, plugs and outlets
Equipment running over capacity

40. ELECTRICAL HAZARDS TO WATCH OUT FOR
Tools that smell, smoke, spark or shock
Wires running across the floor
Electrical cords in contact with hot
appliances or soaked in water
Extension cords instead of permanent
wiring
Octopus connections

41. Electrical Plugs and Extension Cords

42. Electrical Plugs and Extension Cords

43. MEASURES TO PREVENT ELECTRIC SHOCK
Use grounding system
Install GFCI
Isolation of electrical conductors
- Warning signs
Safe Clearance
- Elevation (at least six feet minimum) of electrical
cables specifically at construction site
 Daily inspection & color coded

44. PREVENTIVE MEASURES ON ELECTRIC SHOCK
Insulation
- Use double-insulated royal cord for tools
- Provide good insulation for appliances
Use appropriate PPE
Use Lock-Out and Tag-Out
JHA

45. Ground Fault Circuit Interrupters
Portable Ground Fault Circuit
Interrupters
GFCI Panel Mounts

46. Preventing Electrical Hazards - PPE
Proper foot protection (not tennis shoes)
Rubber insulating gloves, hoods, sleeves, matting,
and blankets
Hard hat (insulated - nonconductive)

47. SIMPLE RULES TO FOLLOW
Do not guess
Use proper instruments
Always use safety devices
LOTO Procedure
Never work alone
Use “DANGER” signs

51. ELECTRICAL
•Water proofing and Dust proofing of electrical Equipment's -For electrical
equipment to be used in tunnels in a non-explosive but dusty and moist
atmosphere, including compressed-air working, the equipment should,
wherever possible, provide protection not less than IP 44
•Electrical Cables -Power supply cables should be fire-retardant and should
produce
low smoke and fumes (especially halogen gases) when involved in a fire.
•Electrical Joints -All power cables should be subjected to an earth continuity
test at 3- monthly intervals and immediately after any alterations, extensions
or damage to the cable concerned.
•Details of all tests carried out should be recorded, including date of test,
voltages
recorded etc
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52. Reference :
•BS 6164 :2011 –Sec 25.3.6 Water proofing and Dust
proofing of electrical Equipment's, 25.4 Cables and
25.4.6 joints
•MMRC Line 3 –OHS& E Manual Safety & Health –Sec
20 Site Electricity
•MBCWR 2007 –Rule No 74 Electrical Hazards