Transcript Slide 1

OVERVIEW OF NFPA 70E
(2004 Edition)
Standards for Electrical Safety-Related
Work Practice Requirements for
Employee Workplaces
Presented By:
Steven Strayer, CIH, CSP, REHS, RS
Cocciardi and Associates, Inc.
(717) 766-4500
(717) 766-3999 (fax)
[email protected]
Electrical Hazards
• Shock – 1,000 fatalities per year, >50% from
<600 volts
• Arc-flash
– 35,000o F
– 2,000 severe burn cases per year
– Kill out to 10 feet
• Arc-blast
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Cu expands 67,000 x’s from solid to gas
Pressures = thousands of pounds per square feet
Noise >160 dB
Molten shrapnel >700 mph
Occupational Safety and Health
Administration (OSHA)
• Worker protection police
• General industry (1910) and construction (1926)
• Subpart “S” – electrical
– Methods to eliminate/minimize electrical
hazards
– Safe work practices (1910.331-335)
– Training requirement (1910.332)
* Problem: Limited specificity (ex. Flash
protection)
NFPA 70E – Standard for Electrical Safety in the
Workplace Background / History
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Assist OSHA in developing workplace safety
(NFPA 70 – NEC: Limited Application)
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Four Parts to 70E
I.
Installation Safety Requirements
Now Chapter 4 (Articles 400 – 450)
II.
Safety Related Work Practices
Now Chapter 1 (Articles 100 – 130)
III.
Safety Related Maintenance Requirements
Now Chapter 2 (Articles 200 – 250)
IV.
Safety Requirements for Special Equipment
Now Chapter 3 (Articles 300 – 340)
History –
• 1979: 1st Edition
(Part I Only)
• 1981: 2nd Edition
(Added Part II)
• 1983: 3rd Edition
(Added Part III)
• 1988: 4th Edition
(Minor Revisions)
• 1995: 5th Edition
(Revised Part I and II)
• 2000: 6th Edition
(Revised Part II and Added IV)
• 2004: 7th Edition
(Revised Title Format, and
primarily Part II)
•NEC format
•Chapters/articles
•Part II now Chapter 1
Scope –
• Public and private premises including
building, structures, mobile homes, RV’s, and
floating buildings
• Yards, lots, parking lots, carnivals, and
industrial sub-stations
• Installations used by electric utilities, such as
offices, buildings, warehouses, garages,
machine shops, recreational that are not an
integral part of a generating plant, sub-station,
or control station
• Conductors that connect installations to a
supply of electricity
Not Covered –
• Installations in ships, watercraft, railway rolling stock,
aircraft, or automotive vehicles other than mobile
homes and RV’s
• Installations underground in mines
• Installation of railways
• Installation of communication equipment (must be
exclusive control of communication utilities)
• Installation under exclusive control of electric utilities
(service laterals/meters, rights-of-ways/easements,
and property [owned or leased] for purpose of
generation, transmission, transformation, etc.)
CHAPTER 1: Safety-Related
Work Practices
“On Hold For Further Examination”
Chapter 2: Safety Related Maintenance Requirements
• Preserving or restoring the condition of electrical
equipment and installations for employee safety.
• Article 200 – Introduction
• Article 205 – General Maintenance Requirements
• Article 210 – Substations, Switchgear Assemblies,
Switchboards, Panel Boards, Motor Control Centers,
and Disconnect Switches
• Article 215 – Premises Wiring
• Article 220 – Controller Equipment
• Article 225 – Fuses and Circuit Breakers
• Article 230 – Rotating Equipment
• Article 235 – Hazardous (Classified) Locations
• Article 240 – Batteries and Battery Rooms
• Article 245 – Portable Electric Tools and Equipment
• Article 250 – Personal Safety and Protective
Equipment (Inspections and Testing)
Chapter 3: Safety Requirements For
Special Equipment
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Special Equipment Includes:
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Article 300 – Introduction
Article 310 – Electrolytic Cells
Article 320 – Batteries/Battery Rooms
Article 330 - Lasers
CHAPTER 4: INSTALLATION SAFETY
REQUIREMENTS
Based on NFPA 70 - NEC
• Article 400 –
General Requirements for Electrical Installations
• Article 410 –
Wiring Design and Protection
• Article 420 –
Wiring Methods, Components, and Equipment for General Use
• Article 430 –
Specific Purpose Equipment and Installations
• Article 440 –
Hazardous (Classified) Locations: Class I, II, and III, Divisions I
and II, and Class I, Zones 0, I and II
• Article 450 –
Special Systems
Chapter 1: SRWP
Article 100 – Definitions
A. Qualified Person
B. Unqualified Person
C. Limited Approach Boundary
D. Restricted Approach Boundary
E. Prohibited Approach Boundary
F. Flash Protection Boundary
G. Energized Electrical Work/Electrically Safe Work
Condition
Article 110 – General
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Practices/Procedures for employees working on or
near energized conductors/circuit parts and
unqualified individuals with other equipment
Change – Multi-employer worksites – “Hazcom”
• Training –
– Risk of electrical hazard not
reduced to a safe level by Chapter 4
– Classroom/OTJ – Degree
determined by risk
– Include emergency procedures:
First Aid/CPR, Methods of Release
• Qualified Persons
– Precautionary Techniques
– PPE
– Insulating/Shielding Materials/Tools
– Test Equipment
– Distinguishing Live Parts
– Determine Nominal/Voltage
– Approach Distances
– Hazard Evaluation (Including Non-electrical)
– OJT personnel if under direct QP supervision
• Unqualified Persons
– Awareness
– Precautions
– Hazards
• Electrical Safety Program
A. Provide awareness and self-discipline
B. ID electrical safety principals
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Inspect/evaluate
Insulation and enclosure integrity
Plan and document procedures
Deenergize
Anticipating the unexpected
ID and minimize hazards
Employee protection
ID appropriate tools
Personnel abilities
Auditing
C. ID Electrical Safety Controls
• Assumed “energized”
• No bare-hand contact
• Deenergizing procedures
• Training
• Equipment use for ID of hazards
• Equipment training
• Categorize tasks
D. ID procedures when working on >50 volts
• Purpose
• Qualifications
• Hazard/extent of task
• Limits of approach
• Safe work practices
• PPE
• Insulating tools/materials
• Special precautions
• Diagrams/details/pictures
• References
E. Hazard/risk evaluation procedures
F. Job briefing(s) – each shift or more
G. Work Permit Procedures
CHAPTER II – General Requirements
For Electrical Work Practices
• On/near exposed electric conductors
• “Electrically safe” work conditions
– Exceptions -  50 volts
– Additional increased hazard
– Operations or equipment design
Article 120 – Establishing On Electrically Safe Work
Condition
* Must follow LO/TO procedures and confirm (Test)*
- Reference 29CFR1910.147
Article 130 – Working On or Near Live Parts
Change –
A. Energized Electrical Work Permit
- Circuit/equipment description
- Justification
- Safe work practices
- Shock hazard analysis and boundaries
- PPE
- Documentation of job briefing
- Authorization
*Exception –
- Voltage measurements
- Testing
- Troubleshooting
B. Shock Hazard Analysis/Boundaries
• Approach Boundaries
–Limited
–Restricted
–Prohibited
• Flash Hazard Analysis and Boundaries
– 4ft ( 600 volts and not greater than
300 kA cycles)
– Calculation of boundary (incident
energy) for >600 volts
• Boundary at 5 j/cm2 (1.2 cal/cm2)
– PPE – Conform to ANSI/ASTM criteria
“Hazard/Risk Category Classification” Table
•Categories 1 – 4 (can be -1)
PPE ranges from t-shirt/pants to flash suits and shields
•Also addresses need for voltage rated gloves and tools
•Clothing material
Category “0” – natural fibers (weight >4.5 oz/yd2) (assume <2
cal/cm2)
Category “1” – flame resistant (4 cal/cm2)
Category “2” – “1” plus cotton underwear (8 cal/cm2)
Category “3” – “2” plus FR coveralls (25 cal/cm2)
Category “4” – “2” plus multi-layer flash suit (40 cal/cm2)
•Synthetics which melt below 600o F
LIMITED APPROACH BOUNDARY
• No unqualified persons, unless advised of hazards,
escorted by QP
• Conditions for qualified persons
– Flash protection
RESTRICTED APPROACH BOUNDARY
• Qualified person: Do not cross or take a conductive
object past, unless:
– Person is insulated
– Live part is insulated
– Person is insulated from other conductive objects
PROHIBITED APPROACH BOUNDARY
• Qualified person
– Only if body part is insulated
PERSONAL PROTECTION
EQUIPMENT (PPE)
• Conform to ANSI/ASTM Standards
– Based on hazard/risk evaluations
• OTHER COMPONENTS:
– Alertness
– Blind reaching
– Illumination: ANSI IES-RP-7-1991
Generally 50-100 foot candles depending
on:
– Age
– Speed
– Accuracy
– Background Reflection
– Conductive Articles
OTHER PROTECTIVE EQUIPMENT
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Insulated tools (within Limited Approach Boundary)
Ropes/handlines
Grounding equipment/GFCI’s
Ladders
Rubber insulating equipment
Physical/mechanical barriers: no closer than
“Restricted Approach Boundary”
Alerting
• Signs/tags
• Barricades
• Attendants
USE OF SPECIFIC SAFETY RELATED
EQUIPMENT AND WORK PRACTICES
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Test instruments
Energizing/de-energizing
Portable electrical equipment
Conductive work locations (GFCI’s)
Connecting plugs
LOCKOUT/TAGOUT PRACTICES
AND DEVICES