ELECTRICAL SAFETY RELATED WORK PRACTICES FOR GENERAL INDUSTRY

1
ELECTRICAL SAFETY RELATED WORK PRACTICESFOR
GENERAL INDUSTRY
2
ELECTRICAL HAZARDS

• What is an electrical hazard?
• Electricity and the Human Body
• Electrocution
• Arc Blasts Pressure Waves
• Secondary Effects

3
Types of Electrical Hazards

• Electrocution
• Arcs Blasts
• Secondary Hazards (fire, falls)

An electrical hazard is any potential threat to
health and or property caused by inadvertent
contact with, or release of, electricial energy.
4
Electrical Shocks

• Resistance of human body varies widely 10,000
  ohms is typical.
• 5mA of sustained current is usually considered
  the threshold value of physiological damage .
• Threshold voltage10,000 ohms x .005 amps or 50
  volts.

5
Electricity and the Human Body

• At 5 mA pain begins.
• At 10 mA paralysis of limbs (arms) occurs.
• At 30 mA breathing stops.
• At 75 mA fibrillation occurs.
• Above 250 mA fibrillation ceases.
• At 4 amps breathing ceases.
• At 5 amps tissue burns.

6
Arc Blasts Pressure Waves

• Injuries deaths due to arc burns are roughly
  one fourth of electrical hazard related
  casualties.
• Radiation burns can kill up to 5 ft
• Arc temperatures up to 30,000 degrees Pressure
  waves created by arc blasts have been known to
  knock walls down at 30 ft!

7
Electricity is the perfect hazard it cant
be seen, smelled or heard!
The grim statistics from the Natonal Safety
Council Between 500-600 people in the U.S. die
by electrocution or arc blast yearly. 350-400
workers die by electrical current
yearly. Electrical accidents are the 8th leading
cause of death in the workplace. All
electrocutions are preventable!
8
THE 4 LINES OF DEFENSE
TRAINING FOR ALL AFFECTED PERSONNEL PROPER
EQUIPMENT SELECTION OF PROPER WORK
PRACTICES PLANNING AND PROCEDURES
9
APPLICATION OF OSHA SRWP IN THE WORKPLACE

• Who Needs Training?
• What Kind of Training?
• Work Practices
• Proper Selection Use of Equipment
• Are Written Procedures Necessary?

10
WHO NEEDS TRAINING?

• Anyone who works on or near enough to exposed
  live parts or parts which might become energized
  (potential hazard) must receive training.
• Examples Electricians, construction crews on
  industrial sites, heavy equipment operators,
  machine operators, janitors-in short, potentialy
  anyone at your facility!

11
WHAT KIND OF TRAINING?

• Training requirements depend on the extent of
  potential exposure.
• Training may be OJT or classroom or both.
• Extent of training depends on whether person is
  qualified or unqualified.

12
Qualified vs Unqualified

• DEFINITION A qualified person (OSHA definition)
  is one who is familiar with the construction and
  operation of the equipment and the hazards
  involved.
• This definition applies to specific equipment.

13
TRAINING

• Training required for both qualified and non
  qualified personnel working on or near parts
  which are energized or might be energized.
• Qualified personnel must be trained in work
  practices, determine nominal working voltage,
  know line clearances.
• Unqualified personnel working in vicinity must be
  trained to extent necessary.

14
Training for Qualified Personnel

• Must be able to identify energized parts.
• Ability to determine nominal workimg voltages.
• Must know applicable clearances vs voltages IAW
  1910.333(c).
• Trained in SRWP as applied to job.

15
Training for Unqualified Personnel

• Unqualified trained to the extent necessary.
• EXAMPLE Housekeeping crews should be shown safe
  cleaning distances from equipment with live
  circuits and instructed in the use of
  nonconductive cleaning techniques in potentally
  conductive locations.

16
Training for Unqualified Personnel (Cont)

• EXAMPLE Machine operators trained in their role
  in LOTO.
• EXAMPLE Fork lift operators instructed by memo
  and verbally to avoid certain overhead line
  locations in your plant.
• EXAMPLE Manufacturing personnel instructed by
  supervisor to avoid barricaded areas.

17
Occupations Requiring Training

• Blue collar supervisors
• Elec/electronic engineers, techs, assemblers
• Electricians and welders
• Industrial machine operators
• mechanics,repairers, painters, riggers,
  roustabouts,stationary engineers

18
Selection and Use of Safety Related Work Practices

• Parts must be deenergized before work except as
  noted in 1910.333(a)(2) and less than 50 volts.
  1910.333(a)(1)
• Work can be performed on energized parts in case
  of infeasibility or increased hazard of
  deenergized parts. 1910.333(a)(2)
• Deenergized parts must be treated as energized or
  locked out. 1910.333(b)(1)

19
Lockout/Tagout (LOTO)

• LOTO subject to OSHA review. 1910.333(b)(2)(i)
• Procedures must be in place before deenergizing
  circuits. 1910.333(b)(2)(ii)
• Rules governing use of locks and tags.
  1910.333(b)(2)(iii)
• Verification of deenergization required.
  1910.333(b)(2)(iv)
• Restart procedures. 1910.333(b)(2)(v)

20
Safety Related Work Practices for Exposed
Energized Parts

• Only qualified personnel may work on energized
  equipment. 1910.333(c)(2)
• Overhead lines. Deenergize or protective
  measures. Minimum approach distances.
  1910.333(c)(3)

21
3 ft for 0-150 volts 3 ft for 151-600 volts
LIVE PARTS
INSULATED PARTS OR WALL
Condition a
3 ft for 0-150 volts 3.5 ft for 151-600 volts
LIVE PARTS
GROUNDED PARTS
Condition b
3 ft for 0-150 vollts 3.5 ft for 151-600 volts
LIVE PARTS
LIVE PARTS
Condition c
WORKING CLEARANCES, LIVE PARTS, 0-600
VOLTS From Table S-1, 29 CFR 1910
22
APPROACH DISTANCES TO LIVE PARTS
Limited Space
Restricted Space
Prohibited Space
Flash Protection Required
Exposed Live Part, Fixed
Flash Protection Boundry
A
B
C
A.Qualified personnel only B. Qualified
personnel, approved plan, PPE. C. All
requirements in B plus specific training risk
assesment. Adapted from NFPA 70E, Ch. 2-21
23
APPROACH DISTANCES TO LIVE PARTS, 300 V LESS
Limited Space
Restricted Space
Prohibited Space
Flash Protection Required
Exposed Live Part, Fixed
Flash Protection Boundry
A
B
C
A.Qualified personnel only B. Qualified
personnel, approved plan, PPE. C. All
requirements in B plus specific training risk
assesment.
Distances from live part to outer boundries
Flash protection 3 feet Limited space 3 1/2
feet Restricted space avoid contact Prohibited
space avoid contact
24
APPROACH DISTANCES TO LIVE PARTS, 751 to 2,000V
Limited Space
Restricted Space
Prohibited Space
Flash Protection Required
Exposed Live Part, Fixed
Flash Protection Boundry
A
B
C
A.Qualified personnel only B. Qualified
personnel, approved plan, PPE. C. All
requirements in B plus specific training risk
assesment.
Distances from live part to outer boundries
Flash protection 4 feet Limited space 4
feet Restricted space 2 feet Prohibited space
3 inches
25
Work Practices (Cont)

• Procedures required for handling all conductive
  materials. 1910.333(c)(6)
• Nonconductive ladders. 1910.333(c)(7)
• Conductive apparel must be insulated.
  1910.333(c)(8)
• Adequate Illumination required. 1910.333(c)(4)
  and ANSI 11.1

26
Work Practices (Cont)

• Safeguards required for housekeeping duties.
  1910.333(c)(9)
• Interlocks only qualified personnel may defeat
  and only on a temporary basis. 1910.333(c)(10)
• Alerting techniques required in exposed hazardous
  locations. 1910.335(b)

27
Electric Power Lighting

• Live load disconnects must be load rated.
  Breakers not marked SWD cannot be used to
  make\break live loads!
• Breakers operated under fault conditions must be
  replaced. Breakers operated under overload should
  be examined.
• It is unlawful to degrade overload protection in
  the workplace!

28
COMMON CORD AND PLUG VIOLATIONS
29
WORKING ON OR NEAR EXPOSED LIVE PARTS REQUIRES
PERSONAL PROTECTIVE EQUIPMENT29 CFR
1910.333(c)(2). EXPOSED BODY PARTS MUST BE
PROTECTED 29 CFR 1910.335(a)(1).
30
Portable Electrical Equipment

• HANDLING Tools shall not be handled by
  connecting cords or unsafely.
• VISUAL INSPECTION FOR DAMAGE.
• Must have grounding conductor or be double
  insulated or be battery operated.
• Tools used in damp or wet locations must be rated
  for use in those environments.
• Attachment plugs cannot be altered!

31
TEST EQUIPMENT

• Only qualified personnel are permitted to use
  test equipment on live circuits.
• Test equipment must be used within ratings.

32
Safeguards for Personnel Protection

• Protective equipment is required in hazardous
  locations. 1910.335(a)(1)
• General Equipment Tools. Insulated tools
  required when working near exposed live parts.
  Includes fuze pullers/installers,ropes,
  shields,etc. 1910.335(a)(2)

33
Are Written Procedures Necessary?

• Written procedures increase training effeciency,
  protect employer and employee.
• Written procedures are required for
  Lockout/Tagout.
• Procedures required for both enclosed and
  confined work spaces. 1910.335(c)(5)

34
Acnowledgements
Ralph H. Lee Electricity and the Human
Body, IEEE Transactions Accident Facts,
National Safety Council, 1996 ed. Jack McDaniel
Work Book for Electrical Safety Related Work
Practices and Lockout/Tagout for General
Industry James G. and James W. Stallcup
Electrical Regulations Simplified