Changes to Part 4 – Work Rules 2017 NESC Changes to Part 4 – Work Rules Presented to Quad-State Instructors, Inc. January 12, 2016 Columbus, Ohio

Proposed Changes

OSHA Impacts CPs reviewed Sept/Oct 2013 Revised 1910.269 / 1926 Subpart V Issued April 11, 2014 Arc Flash Fall Protection MADs NESC Preprint to be finalized June 1st, 2014 SC8 teleconference created new revised comments to bring Part 4 into conformance with OSHA Combine original CPs, RCs and comments into final revisions

Semantics Numerous changes proposed Almost all rejected or withdrawn “in the vicinity of…” to “on or near…” “protect life and property…” to protect persons and property…”

Arc Flash – Rule 410 A3 Revised to match OSHA rules When PPE required What is “clothing” Restrictions on materials

Table 410-1 Footnote 4: Testing was only done on 200A style 16S single socket meters only. 400A style 320-A and multi-meter panels will have higher heat flux rates and will not self-extinguish similar to larger power panels, arc analysis required. Tuscon Electric currently doing testing No CP was received on this so cannot make revision to 2017 code, a TIA will be issued instead

Table 410-1 Footnote 11: Arcs will not self-extinguish when associated transformer is energized. When network protector is open and associated transformer is de-energized, arcs will self-extinguish in under 6 cycles; 8 cal/cm2 clothing recommended Again, no CP received so TIA will be issued

Table 410-1 Recent OSHA LOI indicated they would accept values in Table 410-1 EXCEPT for those values not based on testing. There actually was testing on 480V open air conductors, data was just not given to SC8 Actual testing showed heat values of 3 cal/cm2 so table value is valid.

EPRI All 3 changes discussed are explained FREE download from EPRI! www.epri.com/abstracts/Pages/ ProductAbstract.aspx?ProductId =000000000001022002

410 A3b New exception for low voltage DC For DC systems with voltages from 50 V to 250 V and 8000 amps maximum fault current, in lieu of performing an arc hazard analysis, clothing with a minimum effective arc rating of 5 cal/cm2 shall be used.

411 Protective methods and devices B Devices and equipment 4. Protective goggles Face and eye protection

411 D Signs and tags for employee safety Safety signs and tags required by Part 4, when installed or replaced, shall comply with the current edition of ANSI Z535.1 through ANSI Z535.5

420 G Liquid-cell batteries Rejected a CP to do major rewrite of this rule Forming a working group with SC3 to rewrite for submission to 2022 code cycle.

420 K Fall Protection Revised to match new OSHA fall protection rules in 1910.269 and 1926 Subpart V

422 A Setting, moving, or removing poles in or in the vicinity of near energized electric supply lines 1. When setting, moving, or removing poles in or in the vicinity of energized lines, precautions shall be taken to avoid direct contact of the pole with the energized conductors. Employees shall wear suitable insulating gloves or use other suitable means where voltages may exceed rating of gloves in when handling poles where energized conductors energized at potentials above 750 V can be contacted. Employees performing such work shall not contact the pole with uninsulated parts of their bodies.

441 Energized conductors or parts A. Minimum approach distance 1.a. The line or part is de-energized and grounded per Rule 444D EXCEPTION: For voltages less than 600 V, where the making of the ground is impractical, the line or part may be isolated in lieu of installing temporary protective grounds provided the following conditions are met: (a) the lines and equipment are isolated from all sources and tested to be de-energized, (b) there is no possibility of contact with another energized source, and (c) the hazard of induced voltage is not present.

441 Energized conductors or parts A. Minimum approach distance 1. c. The energized line or part is insulated line or part is insulated from the employee and from any other line or part at a different voltage. Insulated line and parts include those covered with suitable insulation and having metallic shield, sheath, or concentric neutral or semiconducting shield in combination with suitable metallic drainage bonded to an effective bond.

441 Energized conductors or parts Notes at end of 441 A 1 revised Reference to ANSI 516 replaced with reference to 29CFR1910.269 Appendix B. Note 4 now reads For the purpose of Section 44, “reach” is defined as the range of anticipated motion of an employee while performing a task, and “extended reach” is defined as the range of anticipated motion of a conductive object being held by an employee while performing a task.

441 Energized conductors or parts A Minimum approach distance 3. Precautions for approach – Voltages from 301 V to 72.5 kV a. When exposed grounded lines, conductors, or parts are in the work area, they shall be guarded or insulated. EXCEPTION: When work is being performed on parts energized between 300 V and 750 V within equipment enclosures, (e.g. control panels and relay cabinets), insulating or guarding of all exposed grounded lines, conductors, or parts in the work area is not required provided that employees use insulated tools and/or gloves and that exposed grounded lines, conductors and parts are covered to the extent feasible.

441 Energized conductors or parts A. Minimum approach distance 4. Precautions for approach – Voltages above 72.5 kV Entire rule replaced with: When performing live line work, employees shall position themselves so that they are not within the reach or extended reach of the applicable minimum approach distance. In lieu of using the minimum approach distances in Table 441.1, the minimum approach distance in Tables 441.2 through 441.4 may be used provided the per unit transient overvoltage value (T) has been determined through an engineering analysis considering the system design, expected operating conditions, and control measures.

441 Energized conductors or parts Table 441-1 AC live work minimum approach distance Revised values in table to match new OSHA MADs in 1910.269 Footnote 7 change reference from IEEE 516 to 29CFR1910.269 Appendix B.

441 Energized conductors or parts Tables 441-2 to 4 Minimum approach distance tables for transmission voltages Revised to match new OSHA MAD values Tables for distances in feet were left in ft-in format instead of decimal ft format as used by OSHA

444 De-energizing equipment or lines to protect employees C. Operating switches, disconnectors, open points and tagging 2. Air gaps created (e.g. cut or open jumpers) for de-energizing equipment or lines for the purpose of protecting employees shall be tagged and meet minimum clearances as specified in Table 444-1 or separated by a properly rated insulator.

Table 444-1 Minimum Clearances for Open Air Gap

2022 NESC NRECA Representatives on SC8: Principal – Jonathan D. Cox; Northcentral Mississippi EPA Alternate – Robert Harris; NRECA