1. ELECTRICAL SAFETY TASK GROUP
Task Group 5 Risk Assessment and Arc Flash Controls for Normal Operations
Greg Christensen, INL
July 18, 2016

2. PARTICIPANTS Scot Winningham Earl Myott Jennifer Martin Russ Moder
Jerald Kinz
Todd Kujawa
Craig Shaw
Kevin Gurbisz
Tommy Martinez
Jaqueline Mirabal-Martinez
Matthew Giardina
Jackie McAlhaney
Earl Myott
Russ Moder
Mike Minard
Glen Mirocha
Frank Perrotta
Glenn Anderson
Greg Christensen
Robert Fry
Ray Joggerst
Rick Ramirez
Dan Evans
Omar Al Atassi

3. BACKGROUND
NFPA 70E 2015
Employers are responsible for assessing the risk from the arc hazard for employees that interact with electric equipment

4. BACKGROUND
NFPA 70E recognizes arc flash hazards may exist even when equipment is in an enclosed condition.
This includes operators whose only interaction is with the equipment in an enclosed condition.
There are situations where opening or closing a switch or breaker has been a contributing factor to an arc flash event.

5. GOAL Develop a best practice for:
Risk Assessment and recommendations for verifying proper installation, minimum maintenance requirements and no evidence of impending failure for assigning arc flash controls

6. BEST PRACTICE Elements of Best Practice Risk Assessment
Verifying Proper Installation
Minimum inspection, testing and maintenance requirements for overcurrent protection devices (OCPDs)
Verifying no evidence of Impending failure
Additional considerations i.e. engineering controls, configuration, environment, venting, egress, documentation, etc.

7. Documentation required!
ASSESSING RISK
Documentation required!
Installed properly
Maintained properly
Doors closed and secured
Covers in place and secured
No evidence of impending failure
Annex F Risk Assessment has 38 sample questions to ascertain compliance with first two criteria.

8. THRESHOLDS FOR ARC FLASH
≤ 125 KVA at < 240 V and
< 1.2 Volts is exempted
(assumes calculated in accordance with approved method in accordance with NFPA 70E or IEEE 1584)

9. VERIFY INSTALLATION
Electrical Inspection Program – Task Based Risk Assessment
1) Permit - Obtain an Electrical Work Authorization Document or Electrical Installation Permit
2) Engineered - Engineering Design Document that has taken into consideration the environment and application of the equipment to be installed.
3) Inspection or Examination – Inspection performed by a qualified NEC inspector or an AHJ delegated to perform such inspections.
4) Approved or Accepted– The inspection is approved and documented by NEC Inspector or AHJ, & work authorization document or permit is closed.
5) Required Labeling – Visual indication that the installation was performed in accordance with the required by applicable standards. i.e. Stickered

10. VERIFY INSTALLATION
Electrical Inspection Program – Task Based Risk Assessment
Qualified Person’s Initial Observation of Equipment Installation – Real Time Risk Assessment
1) Covers in place (screws, fasteners are engaged)
2) All penetrations are closed or sealed (is venting in the front?)
3) Conduits, Fittings are secured and complete
4) Handle or Switching mechanism is intact (appears functional)
5) Equipment meets field labeling requirements (reviewed in last 5 yrs)
6) No Suspect/Counterfeit/Recalls
7) Field Modifications have been evaluated

11. VERIFY INSTALLATION Resources:
NFPA 70 Definitions: Approved, Qualified Person, Authority Having Jurisdiction
NFPA 70 Article 90.7 & Examination, Identification, Installation and Use of Equipment
NFPA 70 Article Approval of Conductors and Equipment
NFPA 70 Article Arc Flash Hazard Warning Labels
NFPA 70 Article (A) Maximum Available Fault Current Labeling & (B) Modifications
NFPA 70E 2015 Article (D) Arc Flash Risk Assessment Equipment Labeling

12. OVERCURRENT PROTECTION
Need to Maintain overcurrent protection

13. Power Breakers 3 – 5 year Cycle Cleaning and inspection Lubrication
Thermal imaging
Torqueing connections
Mechanical exercise

14. Power Breakers Performance Testing Needed
Secondary or primary current injection
Instantaneous test to validate trip mechanism and arc flash calculation
Ground fault, short term and long term delay to validate equipment protection

15. Molded Case Circuit Breakers
3 – 5 Year Cycle
Cleaning and inspection, torque connections,
Thermal Imaging - Energized, with loading greater than 40% of rating with covers removed
Torque connections to ensure no hot spots
Mechanical exercise

16. Molded Case Circuit Breakers
Performance tests should be performed:
Instantaneous testing performed to validate trip time of breaker and arc analysis results.
Short Term and Long Term Delay should be performed to validate equipment protection

17. Fuses 3 - 5 Year Cycle Cleaning and inspection
Check fuse clips for tightness

18. Tools Torqueing calibrated tools Document and record values
Torque per manufacturer’s requirements
Remote racking equipment

19. Resources and references
NFPA 70E Standard for Electrical Safety in the Workplace 2015 Chapter 2
NFPA 70B Recommended Practice for Electrical Equipment Maintenance
IEEE Recommended Practice for the Selection, Field Testing and Life Expectancy of Molded Case Circuit Breakers for Industrial Applications
NEMA AB 4 Guidelines for Inspection and Preventative Maintenance of Molded Case Circuit Breakers Used in Commercial and Industrial Applications

20. IMPENDING FAILURE QUESTION:
You can’t see inside or the back of the breaker

21. PRACTICAL CONCERNS 25 cal/cm2 Incident Energy Properly installed
Properly maintained
Cover on and secure
no evidence of impending failure
Risk = high consequence/low probability
Consensus of the group some level of PPE is still recommended for this risk.
= Serious injury if event occurs.

22. RISK High Probability Low Probability High Consequence Severity
Low Consequence
Frequency
Upper left quadrant – Beware - here is the problem, the brain is telling you the likelihood (probability) is low so one may take no action to protect from an arc flash (the employee thinks properly installed, properly maintained … hence no PPE required) However if an arc flash does happen the results will be the same as in the upper right quadrant of this table.

23. PPE for OPERATIONS
If bounding conditions are NOT met then arc rated clothing and PPE must meet the available incident energy level
>40 cal/cm2 remote racking or other engineered control to remove the employee from the hazard zone should be employed
Consider Hierarchy of Controls

24. PPE for OPERATIONS
If risk assessment indicates the conditions for proper installation, maintenance and no evidence of impending failure are met:
Underlayer must be non-melting
Minimum for outer layer is non melting
Arc rated clothing recommended > 1.2 cal/cm2

25. CONCLUSION
Risk assessment to evaluate bounding conditions for proper installation, maintenance and no evidence of impending failure must consider many discreet factors to be effective and provide a high level of safety for breaker operations.
See also EFCOG Best Practice #192 “Guide to Incorporating Risk Assessment into ISM for Electrical Safety”

26. POSSIBLE FUTURE GOALS
Each site should evaluate implementation of this process
Survey workers regarding their questions or concerns
Identify lessons learned for implementation
Study accident trends associated with breaker operations

27. QUESTIONS?