DOE Handbook
Electrical Safety
- Contents -

DOE HANDBOOK
ELECTRICAL SAFETY


RF Cafe - U.S. Department of Energy logo

U.S. Department of Energy           AREA SAFT
Washington, D.C. 20585

DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited.

Available on the Department of Energy
Technical Standards Program
Web site at
https://tis.eh.doe.gov/techstds


DOE-HDBK-1092-2004


CONTENTS
FOREWORD.............................................................................ii 
1.0 INTRODUCTION...................................................................1-1 
  1.1 PURPOSE........................................................................1-1 
  1.2 SCOPE..........................................................................1-1 
  1.3 AUTHORITY HAVING JURISDICTION..................................................1-2 
2.0 GENERAL REQUIREMENTS.................... .....................................2-1 
  2.1 ELECTRICAL MAINTENANCE OR REPAIRS..............................................2-1 
    2.1.1 WORK ON ENERGIZED/DEENERGIZED ELECTRICAL EQUIPMENT.........................2-1 
    2.1.2 CONSIDERATIONS FOR WORKING ON ENERGIZED SYSTEMS AND EQUIPMENT..............2-1 
    2.1.3 SAFETY WATCH RESPONSIBILITIES AND QUALIFICATIONS...........................2-2 
  2.2 BASIC SAFEGUARDS...............................................................2-2 
  2.3 RESPONSIBILITIES...............................................................2-3 
    2.3.1 MANAGEMENT RESPONSIBILITIES................................................2-3 
    2.3.2 EMPLOYEE RESPONSIBILITIES..................................................2-3 
  2.4 REVIEWS/INSPECTIONS............................................................2-4 
  2.5 APPROVAL OF ELECTRICAL EQUIPMENT...............................................2-4 
  2.6 CODES, STANDARDS, AND REGULATIONS..............................................2-4 
  2.7 GROUND FAULT CIRCUIT INTERRUPTERS AND ARC FAULT CIRCUIT INTERRUPTERS...........2-5 
    2.7.1 HOW A GFCI WORKS...........................................................2-5 
    2.7.2 USES.......................................................................2-6 
    2.7.3 ARC FAULT CIRCUIT INTERRUPTERS.............................................2-7 
    2.8 TRAINING AND QUALIFICATIONS OF QUALIFIED WORKERS.............................2-8 
    2.8.1 FORMAL TRAINING AND QUALIFICATIONS.........................................2-8 
    2.8.2 TRAINING OF SAFETY PERSONNEL...............................................2-9 
    2.9 WORKING SPACE AROUND ELECTRICAL EQUIPMENT....................................2-9 
    2.9.1 ELECTRICAL EQUIPMENT RATED AT 600 VOLTS OR LESS............................2-9 
    2.9.2 ELECTRICAL EQUIPMENT RATED OVER 600 VOLTS..................................2-11 
    2.10 IDENTIFICATION OF DISCONNECTION MEANS.......................................2-12 
    2.10.1 DISCONNECTING MEANS.......................................................2-12 
    2.10.2 PANELBOARD CIRCUIT DIRECTORIES............................................2-12 
    2.10.3 ENCLOSURE LABELING........................................................2-12 
    2.10.4 LOAD LABELING.............................................................2-12 
    2.10.5 SOURCE LABELING...........................................................2-12
iii 
  2.11 WORK INSTRUCTIONS.............................................................2-13 
    2.11.1 SAFE WORK INSTRUCTIONS AND SUPERVISION....................................2-13 
  2.12 ELECTRICAL PERSONAL PROTECTIVE EQUIPMENT......................................2-14 
    2.12.1 MANAGEMENT'S RESPONSIBILITIES.............................................2-14 
    2.12.2 INSPECTING PPE............................................................2-14 
    2.12.3 CLEANING AND ELECTRICAL TESTING OF PPE....................................2-15 
      2.12.3.1 TESTING...............................................................2-15 
      2.12.3.2 TESTING APPARATUS.....................................................2-15 
      2.12.3.3 RETESTED PPE..........................................................2-15 
    2.12.4 LIVE-LINE TOOLS...........................................................2-15 
      2.12.4.1 FIBERGLASS-HANDLED TOOLS..............................................2-15 
      2.12.4.2 WOODEN-HANDLED TOOLS..................................................2-15 
    2.12.5 MAXIMUM USAGE VOLTAGE.....................................................2-16 
    2.12.6 MAXIMUM USAGE VOLTAGE FOR LIVE-LINE TOOLS.................................2-16 
    2.12.7 RUBBER-INSULATED GLOVES...................................................2-16 
    2.12.8 STORAGE...................................................................2-16 
    2.12.9 SAFETY SHOES, HARDHATS, AND GLASSES.......................................2-16 
  2.13 WORK PRACTICES................................................................2-17 
    2.13.1 TRAINING..................................................................2-17 
      2.13.1.1 LIVE PARTS............................................................2-17 
      2.13.1.2 SAFE PROCEDURE........................................................2-17 
      2.13.1.3 CIRCUITS AND EQUIPMENT................................................2-17 
      2.13.1.4 STORED ELECTRICAL ENERGY..............................................2-18 
      2.13.1.5 STORED NONELECTRICAL ENERGY...........................................2-18 
      2.13.1.6 LOCKOUT/TAGOUT PROCEDURE..............................................2-18 
    2.13.2 VERIFICATION OF DEENERGIZED CONDITION.....................................2-18 
      2.13.2.1 VOLTAGE VERIFICATION TEST.............................................2-18 
      2.13.2.2 APPLICATION OF GROUNDS................................................2-19 
    2.13.3 REENERGIZING EQUIPMENT....................................................2-19 
      2.13.3.1 TESTS AND VISUAL INSPECTIONS..........................................2-19 
      2.13.3.2 WARNING EMPLOYEES.....................................................2-19 
      2.13.4.1 APPROACH DISTANCE.....................................................2-20 
      2.13.4.2 TWO WORKERS...........................................................2-20 
      2.13.4.4 ILLUMINATION..........................................................2-20 
      2.13.4.5 SYSTEMS UNDER LOAD....................................................2-20 
      2.13.4.6 WORKING WITH TEST INSTRUMENTS AND EQUIPMENT...........................2-20 
      2.13.4.  6.1 QUALIFIED EMPLOYEES...............................................2-21 
iv 
      2.13.4.6.2 VISUAL INSPECTIONS..................................................2-21 
      2.13.4.6.3 RATING INSTRUMENTS AND EQUIPMENT....................................2-21 
      2.13.4.6.4 CALIBRATION OF ELECTRICAL INSTRUMENTS...............................2-21 
3.0 ELECTRICAL PREVENTIVE MAINTENANCE............................................3-1 
  3.1 DEVELOPMENT AND IMPLEMENTATION REQUIREMENTS....................................3-1 
  3.2 DEFINITION.....................................................................3-1 
  3.3 MAINTENANCE....................................................................3-1 
  3.4 INSPECTION.....................................................................3-1 
  3.5 ESSENTIAL ELEMENTS.............................................................3-3 
  3.6 PLANNING AND DEVELOPING AN EPM PROGRAM; FUNDAMENTALS OF EPM....................3-3 
  3.7 GROUND-FAULT PROTECTION........................................................3-3 
4.0 GROUNDING.......................................................................4-1 
  4.1 REGULATIONS, CODES, AND REFERENCES.............................................4-1 
    4.1.1 ENGINEERING SPECIFICATIONS AND DRAWINGS....................................4-1 
  4.2 CIRCUIT AND SYSTEM GROUNDING...................................................4-1 
  4.3 EQUIPMENT GROUNDING............................................................4-1 
  4.4 BONDING........................................................................4-2 
  4.5 GROUNDED OR UNGROUNDED SYSTEMS.................................................4-3 
    4.5.1 GROUNDED SYSTEMS...........................................................4-4 
    4.5.2 UNGROUNDED SYSTEMS.........................................................4-5 
    4.5.3 HIGH-IMPEDANCE GROUNDING...................................................4-5 
  4.6 GROUNDING REQUIREMENTS.........................................................4-6 
  4.7 GROUNDING ELECTRODE CONDUCTOR..................................................4-7 
    4.7.1 SIZING THE GROUNDING ELECTRODE CONDUCTOR...................................4-8 
    4.7.2 EXCEPTIONS TO NEC 250.6  6.................................................4-8 
  4.8 MAIN BONDING JUMPER............................................................4-9 
  4.9 SYSTEM WITH GROUNDED CONDUCTOR.................................................4-10 
  4.10 EQUIPMENT GROUNDING CONDUCTOR.................................................4-12 
    4.10.1 SIZING THE EQUIPMENT GROUNDING CONDUCTOR..................................4-12 
    4.10.2 SEPARATE EQUIPMENT GROUNDING CONDUCTORS...................................4-13 
  4.11 UNGROUNDED SYSTEMS............................................................4-13 
  4.12 GROUNDING A SEPARATELY DERIVED SYSTEM.........................................4-14 
  4.13 GROUNDING ELECTRODE SYSTEM....................................................4-15 
  4.14 GROUND-FAULT PROTECTION OF EQUIPMENT..........................................4-16 
  4.15 PERSONNEL PROTECTIVE GROUNDS..................................................4-16 
    4.15.1 PURPOSE OF PERSONNEL PROTECTIVE GROUNDS...................................4-16 
    4.1  5.2 CRITERIA FOR PERSONNEL PROTECTIVE GROUNDS...............................4-17 
v 
    4.15.3 GROUNDING CLAMPS..........................................................4-18 
    4.15.4 SCREW-TIGHTENING DEVICES..................................................4-18 
    4.15.5 GROUNDING CABLE LENGTH....................................................4-18 
    4.15.6 GROUNDING CABLE CONNECTION................................................4-18 
    4.15.7 CONNECTING GROUNDING CABLES IN SEQUENCE...................................4-18 
    4.15.8 REMOVING PROTECTIVE GROUNDS...............................................4-18 
    4.15.9 PROTECTIVE APPAREL AND EQUIPMENT..........................................4-18 
5.0 SPECIAL OCCUPANCIES............................................................5-1 
  5.1 EXPLOSIVES.....................................................................5-1 
    5.1.1 EVACUATION.................................................................5-1 
    5.1.2 SHUTDOWN OF OPERATIONS.....................................................5-1 
    5.1.3 LIGHTNING PROTECTION.......................................................5-1 
    5.1.4 STATIC ELECTRICITY.........................................................5-2 
      5.1.4.1 BONDING AND GROUNDING EQUIPMENT........................................5-2 
      5.1.4.2 TESTING EQUIPMENT GROUNDING SYSTEMS....................................5-2 
      5.1.4.3 CONDUCTIVE FLOORS, SHOES, MATS, AND WRISTBANDS.........................5-3 
      5.1.4.4 SPECIFICATIONS FOR CONDUCTIVE FLOORS AND WRISTBANDS....................5-3 
      5.1.4.5 CONDUCTIVE FLOOR TEST..................................................5-3 
      5.1.4.6 HUMIDIFICATION.........................................................5-4 
      5.1.4.7 GROUND-FAULT CIRCUIT INTERRUPTER.......................................5-5 
    5.1.5 ELECTRICAL EQUIPMENT AND WIRING............................................5-5 
      5.1.5.1 PERMANENT EQUIPMENT AND WIRING.........................................5-5 
      5.1.5.2 HAZARDOUS LOCATIONS....................................................5-5 
      5.1.5.3 ELECTRICAL SUPPLY SYSTEMS..............................................5-6 
      5.1.5.4 BUILDING SERVICE ENTRANCE..............................................5-7 
    5.1.6 TESTING....................................................................5-7 
      5.1.6.1 TEST SETUP.............................................................5-8 
      5.1.6.2 PIN SWITCHES AND OTHER NONINITIATING CIRCUITS..........................5-8 
      5.1.6.3 LIGHTNING STORMS.......................................................5-8 
      5.1.6.4 LOW-ENERGY ELECTROEXPLOSIVE DEVICES....................................5-8 
      5.1.6.5 WARNING SIGNALS........................................................5-11 
      5.1.6.6 FIRING LEADS...........................................................5-11 
      5.1.6.7 ELECTRICAL TESTING INSTRUMENTS FOR USE WITH EXPLOSIVES SYSTEMS.........5-11 
        5.1.6.  7.1 CLASSIFICATION...................................................5-11 
        5.1.6.  7.2 CERTIFICATION....................................................5-11 
        5.1.6.  7.3 ELECTRICAL TESTING INSTRUMENTS FOR USE WITH INITIATING
                    ELECTRICAL CIRCUITS..............................................5-12 
vi 
        5.1.6.7.4 ELECTRICAL TESTING INSTRUMENTS FOR USE WITH NONINITIATING
                  ELECTRICAL CIRCUITS................................................5-12 
  5.2 PREVENTION OF EXTERNAL IGNITION AND EXPLOSION..................................5-12 
    5.2.1 SOURCES OF IGNITION........................................................5-13 
    5.2.2 COMBUSTION PRINCIPLES......................................................5-14 
    5.2.3 EVALUATION OF HAZARDOUS AREAS..............................................5-14 
    5.2.4 INTRINSICALLY SAFE EQUIPMENT...............................................5-14 
    5.2.5 ENCLOSURES.................................................................5-14 
    5.2.6 PURGING/PRESSURIZATION SYSTEMS.............................................5-16 
  5.3 HAZARDOUS LOCATIONS............................................................5-17 
    5.3.1 CLASS I....................................................................5-17 
      5.3.1.1 DIVISION 1.............................................................5-17 
      5.3.1.2 DIVISION 2.............................................................5-21 
    5.3.2 CLASS II...................................................................5-21 
      5.3.2.1 CLASS II DIVISION 1....................................................5-21 
      5.3.2.2 CLASS II DIVISION 2....................................................5-23 
    5.3.3 GROUPS.....................................................................5-23 
    5.3.4 IGNITION TEMPERATURE.......................................................5-23 
    5.3.5 FLAMMABLE (EXPLOSION) LIMITS...............................................5-23 
    5.3.6 FLASHPOINT.................................................................5-24 
  5.4 ELECTRICAL EQUIPMENT FOR CLASS I, II, AND III AREAS............................5-24 
    5.4.1 SEALS AND DRAINS...........................................................5-24 
      5.4.1.1 SEALS..................................................................5-24 
      5.4.1.2 DRAINS.................................................................5-25 
      5.4.1.3 SELECTION OF SEALS AND DRAINS..........................................5-25 
        5.4.1.3.1 PRIMARY CONSIDERATIONS.............................................5-25 
        5.4.1.3.2 TYPES OF SEALING FITTINGS..........................................5-26 
  5.5 MANUFACTURERS' DIGEST..........................................................5-26 
  5.6 DESCRIPTIONS, FEATURES, AND TEST CRITERIA OF ENCLOSURES FOR HAZARDOUS
      (CLASSIFIED) LOCATIONS (PER NEMA 250)..........................................5-27 
  5.7 TYPE 7 ENCLOSURES..............................................................5-27 
    5.7.1 DESCRIPTION AND APPLICATION................................................5-27 
    5.7.2 FEATURES AND TEST CRITERIA.................................................5-28 
  5.8 TYPE 8 ENCLOSURES..............................................................5-28 
    5.8.1 DESCRIPTION AND APPLICATION................................................5-28 
    5.8.2 FEATURES AND TEST CRITERIA.................................................5-28 
  5.9 TYPE 9 ENCLOSURES..............................................................5-29 
    5.9.1 DESCRIPTION AND APPLICATION................................................5-29 
vii 
    5.9.2 FEATURES AND TEST CRITERIA.................................................5-29 
  5.10 UNDERGROUND FACILITIES........................................................5-29 
    5.10.1 WORK ON ELECTRICAL EQUIPMENT AND CIRCUITS.................................5-30 
    5.10.2 GROUNDING.................................................................5-31 
    5.10.3 POWER CABLES AND CONDUCTORS...............................................5-31 
    5.10.4 TRAILING CABLES...........................................................5-32 
    5.10.5 TROLLEY CIRCUITS FOR TRACK HAULAGE........................................5-32 
6.0 REQUIREMENTS FOR SPECIFIC EQUIPMENT...........................................6-1 
  6.1 CONVEYING SYSTEMS..............................................................6-1 
    6.1.1 ELECTRICAL DESIGN CRITERIA.................................................6-1 
  6.2 CRANES AND HOISTS..............................................................6-2 
    6.2.1 NEC GENERAL REQUIREMENTS...................................................6-2 
    6.2.2 DISCONNECTING MEANS........................................................6-3 
    6.2.3 GROUNDING..................................................................6-4 
    6.2.4 CONTROL....................................................................6-4 
    6.2.5 CLEARANCES.................................................................6-5 
    6.2.6 OSHA AND NEC REQUIREMENTS..................................................6-5 
    6.2.7 MAINTENANCE AND OPERATIONS.................................................6-5 
    6.2.8 DOCUMENTED MAINTENANCE.....................................................6-5 
    6.2.9 MECHANICAL ELEVATING AND ROTATING EQUIPMENT................................6-6 
  6.3 ELEVATORS AND ESCALATORS.......................................................6-7 
    6.3.1 CODES AND STANDARDS........................................................6-7 
    6.3.2 DESIGN SPECIFICATIONS......................................................6-7 
      6.3.2.1 VOLTAGE AND CURRENT LIMITATIONS........................................6-7 
      6.3.2.2 CONDUCTORS.............................................................6-8 
      6.3.2.3 DISCONNECTING MEANS....................................................6-8 
      6.3.2.4 MOTORS.................................................................6-9 
      6.3.2.5 GROUNDING..............................................................6-9 
      6.3.2.6 OVERSPEED PROTECTION...................................................6-9 
    6.3.3 EMERGENCY POWER............................................................6-9 
    6.3.4 DESIGN.....................................................................6-9 
    6.3.5 FIRE PROTECTION............................................................6-10 
    6.3.6 INSPECTIONS AND RECORDS....................................................6-11 
      6.3.6.1 CODES..................................................................6-11 
      6.3.6.2 INSPECTOR QUALIFICATIONS...............................................6-11 
  6.4 PORTABLE AND VEHICLE-MOUNTED GENERATORS........................................6-11 
  6.5 BATTERIES......................................................................6-12 
viii 
    6.5.1 SURROUNDING SPACE..........................................................6-12 
    6.5.2 LOCATION...................................................................6-12 
    6.5.3 VENTILATION................................................................6-12 
    6.5.4 CONDUIT....................................................................6-13 
    6.5.5 BATTERY ROOM...............................................................6-13 
    6.5.6 PERSONAL PROTECTIVE EQUIPMENT..............................................6-13 
    6.5.7 TOOLS......................................................................6-13 
    6.5.8 STORAGE BATTERIES AND BATTERY BANKS........................................6-14 
      6.5.8.1 TYPES OF HAZARDS.......................................................6-14 
      6.5.8.2 DESIGN AND CONSTRUCTION CRITERIA.......................................6-14 
      6.5.8.3 OPERATING CRITERIA.....................................................6-15 
7.0 WORK IN EXCESS OF 600 VOLTS....................................................7-1 
  7.1 RESPONSIBILITIES FOR SAFETY....................................................7-1 
    7.1.1 WORKERS....................................................................7-1 
    7.1.2 SUPERVISORS................................................................7-2 
  7.2 TRAINING.......................................................................7-3 
    7.2.1 EMPLOYEE TRAINING..........................................................7-3 
    7.2.2 QUALIFIED EMPLOYEE TRAINING................................................7-3 
  7.3 JOB BRIEFINGS..................................................................7-3 
  7.4 PERSONAL PROTECTIVE EQUIPMENT AND PROTECTIVE CLOTHING..........................7-4 
    7.4.1 SHOES......................................................................7-4 
    7.4.2 HARDHATS...................................................................7-4 
    7.4.3 EYE PROTECTORS.............................................................7-5 
    7.4.5 METAL FASTENERS............................................................7-5 
    7.4.6 WORK GLOVES................................................................7-5 
    7.4.7 WORK CLOTHES...............................................................7-5 
    7.4.8 FIRE-RESISTANT (FR) CLOTHING...............................................7-5 
      7.4.8.1 GENERAL................................................................7-5 
      7.4.8.2 ELECTRIC ARC HAZARDS...................................................7-5 
      7.4.8.3 TYPES OF FIRE RESISTANT FABRICS........................................7-6 
      7.4.8.4 CLOTHING SYSTEMS.......................................................7-6 
    7.4.9 RUBBER GLOVES..............................................................7-6 
    7.4.10 RUBBER LINE HOSE, HOODS, COVERS, SLEEVES, AND BLANKETS....................7-7 
    7.4.11 LIVE LINE TOOLS...........................................................7-7 
    7.4.12 STOREROOM STORAGE.........................................................7-7 
    7.4.13 TRUCK STORAGE.............................................................7-7 
    7.4.14 PLACING OF INSULATING GOODS ON CONDUCTORS.................................7-8 
ix 
    7.4.15 REMOVING INSULATING GOODS FROM CONDUCTORS.................................7-8 
    7.4.16 CLEANING AND INSPECTING...................................................7-8 
  7.5 PROTECTIVE GROUNDING OF LINES AND EQUIPMENT....................................7-8 
    7.5.1 PURPOSE....................................................................7-8 
      7.5.1.1 REDUCE THE POTENTIAL VOLTAGE DIFFERENCES ACROSS THE WORKER.............7-9 
    7.5.2 APPLICATION................................................................7-9 
      7.5.2.1 DEENERGIZED LINES......................................................7-9 
      7.5.2.2 NEW CONSTRUCTION OR DISMANTLING OF FACILITIES..........................7-10 
      7.5.2.3 MINIMUM APPROACH DISTANCE FROM UNGROUNDED CONDUCTORS...................7-10 
      7.5.2.4 VISIBLE THREE-PHASE SHORT AND GROUND REQUIRED..........................7-10 
      7.5.2.5 GROUND CIRCUIT.........................................................7-10 
    7.5.3 GROUNDING EQUIPMENT........................................................7-11 
      7.5.3.1 AVAILABILITY...........................................................7-11 
      7.5.3.2 APPROVED CAPACITY......................................................7-11 
      7.5.3.3 GROUNDING CABLES AND HARDWARE..........................................7-11 
      7.5.3.4 GROUNDING CABLES.......................................................7-11 
        7.5.3.4.1 STRANDING..........................................................7-11 
        7.5.3.4.2 JACKETS............................................................7-11 
        7.5.3.4.3 FERRULES...........................................................7-12 
        7.5.3.4.4 HANDLING OF GROUNDING CABLE........................................7-12 
        7.5.3.4.5 SIZE OF GROUNDING CABLE............................................7-12 
        7.5.3.4.6 GROUNDING CABLE LENGTH.............................................7-12 
        7.5.3.4.7 GROUNDING CLAMPS...................................................7-12 
          7.5.3.4.7.1 CLAMP TYPES....................................................7-12 
          7.5.3.4.7.2 CLAMP JAWS.....................................................7-13 
        7.5.3.4.8 GROUNDING CLUSTER BARS.............................................7-13 
        7.5.3.4.9 TEMPORARY GROUND RODS..............................................7-13 
    7.5.4 TESTING BEFORE INSTALLING GROUNDS..........................................7-14 
    7.5.5 ATTACHING AND REMOVING GROUNDS.............................................7-14 
      7.5.6.1 WORK LOCATION..........................................................7-14 
      7.5.6.3 OTHER LOCATIONS........................................................7-15 
    7.5.7 TESTING WITHOUT GROUNDS....................................................7-15 
    7.5.8 GROUND PERSONNEL...........................................................7-15 
  7.6 INSTALLING OR REMOVING CONDUCTORS..............................................7-15 
    7.6.1 WORKING ON ENERGIZED LINE OR EQUIPMENT.....................................7-15 
    7.6.2 STRINGING OR REMOVING DEENERGIZED CONDUCTORS...............................7-16 
    7.6.3 STRINGING ADJACENT TO ENERGIZED LINES......................................7-17 
x 
  7.7 SPECIAL TOOLS..................................................................7-18 
    7.7.1 LINEWORKERS’ CLIMBING TOOLS................................................7-18 
    7.7.2 BODY BELTS AND SAFETY STRAPS...............................................7-18 
    7.7.3 TOOL BAG AND EQUIPMENT.....................................................7-19 
    7.7.4 TAPES AND RULERS...........................................................7-19 
    7.7.5 SPOON AND SHOVELS..........................................................7-19 
    7.7.6 PIKE POLES.................................................................7-20 
    7.7.7 HAND AXES AND SHARP TOOLS..................................................7-20 
    7.7.8 HANDLINES AND TAGLINES.....................................................7-20 
  7.8 TREE TRIMMING..................................................................7-20 
    7.8.1 CARE AND USE OF TOOLS......................................................7-20 
    7.8.2 CLIMBING...................................................................7-20 
  7.9 SERIES STREET-LIGHTING CIRCUITS AND APPARATUS..................................7-21 
  7.10 UNDERGROUND...................................................................7-21 
    7.10.1 WORKING IN MANHOLES, UTILITY TUNNELS, AND VAULTS..........................7-21 
    7.10.2 WORKING ON ENERGIZED UNDERGROUND CABLES...................................7-23 
    7.10.3 TERMINALS OF UNDERGROUND CABLES (POTHEADS)................................7-23 
  7.11 FERRO-RESONANCE...............................................................7-23 
8.0 TEMPORARY WIRING...............................................................8-1 
  8.1 REQUIREMENTS AND INSTALLATION CONDITIONS OF USE................................8-1 
    8.1.1 CONTACT PREVENTION.........................................................8-1 
    8.1.2 VERTICAL CLEARANCES........................................................8-1 
    8.1.3 WET LOCATIONS..............................................................8-1 
    8.1.4 SUPPORTS...................................................................8-1 
    8.1.5 CONDUIT....................................................................8-2 
    8.1.6 LIGHTING...................................................................8-2 
    8.1.7 CONFINED SPACES............................................................8-2 
    8.1.8 EXPOSED SOCKETS AND BROKEN BULBS...........................................8-2 
    8.1.9 GROUND FAULT PROTECTION FOR PERSONNEL......................................8-2 
    8.1.10 WIRING METHODS............................................................8-2 
      8.1.10.1 SERVICE CONDUCTORS....................................................8-3 
      8.1.10.2 FEEDER CONDUCTORS.....................................................8-3 
      8.1.10.3 BRANCH CIRCUIT CONDUCTORS.............................................8-3 
      8.1.10.4 NONMETALLIC SHEATHED CABLE............................................8-3 
  8.2 USING ASSURED EQUIPMENT GROUNDING CONDUCTOR PROGRAM............................8-3 
  8.3 PORTABLE ELECTRICAL TOOLS AND EQUIPMENT........................................8-5 
    8.3.1 INSPECTION AND MAINTENANCE.................................................8-5 
xi 
    8.3.2 CONDITIONS OF USE..........................................................8-6 
    8.3.3 USE OF EXTENSION CORDS.....................................................8-6 
    8.3.4 DOUBLE INSULATED TOOLS.....................................................8-6 
9.0 ENCLOSED ELECTRICAL/ELECTRONIC EQUIPMENT.....................................9-1 
  9.1 PURPOSE........................................................................9-1 
  9.2 SCOPE..........................................................................9-1 
  9.3 GROUNDING AND BONDING..........................................................9-1 
    9.3.1 OBJECTIONAL CURRENT OVER GROUNDING CONDUCTORS..............................9-1 
    9.3.2 EQUIPMENT GROUNDING CONDUCTOR..............................................9-2 
    9.3.3 ENCLOSURE GROUNDING AND BONDING............................................9-3 
    9.3.4 SPECIAL CONSIDERATIONS.....................................................9-5 
  9.4 RACK POWER DISTRIBUTION........................................................9-6 
    9.4.1 GENERAL REQUIREMENTS APPLYING TO ALL AC POWER EQUIPMENT WITHIN OR
          ATTACHED TO INSTRUMENT RACKS...............................................9-6 
      9.4.1.1 LOADS..................................................................9-6 
      9.4.1.2 OTHER GENERAL EQUIPMENT REQUIREMENTS...................................9-6 
    9.4.2 CONDUCTORS AND CABLES SPECIFIC REQUIREMENTS................................9-6 
      9.4.2.1 FLEXIBLE CABLES........................................................9-7 
      9.4.2.2 STRAIN RELIEF..........................................................9-7 
      9.4.2.3 SEPARATION OF VOLTAGES.................................................9-7 
      9.4.2.4 OTHER CONCERNS.........................................................9-8 
    9.4.3 POWER SWITCHES AND INTERLOCK DEVICES SPECIFIC REQUIREMENTS.................9-8 
  9.5 CHASSIS POWER DISTRIBUTION.....................................................9-8 
    9.5.1 AC POWER DISTRIBUTION......................................................9-8 
      9.5.1.1 CHASSIS BONDING AND GROUNDING..........................................9-8 
      9.5.1.2 CONNECTIONS, CONNECTORS, AND COUPLINGS.................................9-9 
      9.5.1.3 TERMINALS/LIVE PARTS...................................................9-10 
    9.5.2 DC POWER DISTRIBUTION......................................................9-10 
  9.6 PROTECTIVE DEVICES FOR ENCLOSED ELECTRICAL/ ELECTRONIC EQUIPMENT...............9-10 
    9.6.1 SURGE ARRESTERS............................................................9-10 
    9.6.2 FUSES......................................................................9-11 
    9.6.3 CIRCUIT BREAKERS...........................................................9-11 
    9.6.4 POWER INTERLOCK DEVICES....................................................9-11 
  9.7 DISCONNECTING MEANS............................................................9-11 
    9.7.1 GENERAL....................................................................9-12 
    9.7.2 EMERGENCY SHUTDOWN.........................................................9-12 
    9.7.3 SPECIAL CONSIDERATIONS.....................................................9-12 
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  9.8 MARKING AND LABELING REQUIREMENTS..............................................9-13 
    9.8.1 GENERAL MARKING REQUIREMENTS...............................................9-13 
    9.8.2 HAZARD MARKING REQUIREMENTS................................................9-13 
    9.8.3 OTHER REQUIREMENTS.........................................................9-13 
  9.9 WORKING CLEARANCES.............................................................9-14 
  9.10 CABLE/UTILITY MANAGEMENT SYSTEM...............................................9-15 
    9.10.1 USAGE WITH ENCLOSED ELECTRICAL/ELECTRONIC EQUIPMENT.......................9-15 
    9.10.2 REQUIREMENTS..............................................................9-16 
  9.11 ELECTRICAL SAFETY REQUIREMENTS FOR TESTER FACILITIES..........................9-17 
    9.11.1 AMPACITY OF FACILITY WIRING AND DISTRIBUTION EQUIPMENT....................9-17 
    9.11.2 FACILITY GROUNDING AT TEMPORARY OR REMOTE SITES...........................9-17 
    9.11.3 FACILITY LIGHTNING PROTECTION.............................................9-18 
    9.11.4 SURGE PROTECTION..........................................................9-18 
  9.12 ENCLOSED POWER ELECTRONICS....................................................9-18 
      9.12.1 ENCLOSURES..............................................................9-18 
    9.12.2 COMPONENT CLEARANCES......................................................9-18 
    9.12.3 INSTRUMENTATION...........................................................9-19 
    9.12.4 GENERAL...................................................................9-19 
  9.13 NON-IONIZING RADIATION........................................................9-20 
    9.13.1 ELECTROMAGNETIC RADIATION.................................................9-20 
    9.13.2 ELECTROMAGNETIC RADIATION THREAT TO ELECTROEXPLOSIVE DEVICES..............9-20 
10.0 RESEARCH & DEVELOPMENT.......................................................10-1 
  10.1 PURPOSE.......................................................................10-1 
  10.2 SCOPE.........................................................................10-1 
  10.3 COMPLIANCE WITH OSHA..........................................................10-1 
  10.4 STANDARDIZED SAFETY PRACTICES AND PROCEDURES..................................10-2 
  10.5 EQUIPMENT NOT LISTED BY A NATIONALLY RECOGNIZED TESTING LABORATORY ...........10-2 
    10.5.1 HAZARDS...................................................................10-2 
    10.5.2 DESIGN AND CONSTRUCTION...................................................10-2 
  10.6 OPERATION AND MAINTENANCE.....................................................10-4 
  10.7 EMPLOYEE QUALIFICATIONS.......................................................10-4 
    10.7.1 HAZARDS...................................................................10-4 
    10.7.2 ADDITIONAL QUALIFICATIONS.................................................10-4 
  10.8 GENERIC R&D EQUIPMENT.........................................................10-4 
    10.8.1 POWER SOURCES.............................................................10-5 
      10.8.1.1 HAZARDS...............................................................10-5 
xiii 
      10.8.1.2 DESIGN AND CONSTRUCTION...............................................10-5 
      10.8.1.3 OPERATION AND MAINTENANCE.............................................10-6 
    10.8.2 CONDITIONS OF LOW VOLTAGE AND HIGH CURRENT................................10-6 
      10.8.2.1 HAZARDS...............................................................10-6 
      10.8.2.2 DESIGN AND CONSTRUCTION...............................................10-7 
      10.8.2.3 OPERATION AND MAINTENANCE.............................................10-8 
    10.8.3 CONDITIONS OF HIGH VOLTAGE AND LOW CURRENT................................10-8 
      10.8.3.1 HAZARDS...............................................................10-8 
      10.8.3.2 DESIGN CONSIDERATIONS.................................................10-8 
      10.8.3.3 SAFETY PRACTICES......................................................10-9 
    10.8.4 RADIO-FREQUENCY/ MICROWAVE RADIATION AND FIELDS...........................10-9 
      10.8.4.1 HAZARDS...............................................................10-9 
      10.8.4.2 DESIGN AND CONSTRUCTION...............................................10-10 
      10.8.4.2.1 EXEMPTIONS FROM RFMW EXPOSURE LIMITS................................10-10 
      10.8.4.2.2 EXPOSURE CRITERIA FOR PULSED RFMW RADIATION.........................10-11 
  10.9 METHODS.......................................................................10-13 
    10.9.1 WIRING METHODS............................................................10-13 
      10.9.1.1 HAZARDS...............................................................10-13 
      10.9.1.2 DESIGN AND CONSTRUCTION...............................................10-14 
      10.9.1.2.1 DESIGN AND CONSTRUCTION AS AN INTEGRAL PART OF EQUIPMENT............10-14 
      10.9.1.2.2 POWER SUPPLY INTERFACE BETWEEN UTILITY SYSTEMS AND R&D EQUIPMENT....10-14 
      10.9.1.3 OPERATION AND MAINTENANCE.............................................10-15 
    10.9.2 UNCONVENTIONAL PRACTICES..................................................10-15 
      10.9.2.1 GROUNDING.............................................................10-15 
      10.9.2.1.1 HAZARDS.............................................................10-15 
      10.9.2.1.2 DESIGN AND CONSTRUCTION.............................................10-15 
      10.9.2.1.3 NOISE COUPLING MECHANISMS...........................................10-16 
      10.9.2.1.4 OPERATION AND MAINTENANCE...........................................10-20 
      10.9.2.2 MATERIALS USED IN AN UNCONVENTIONAL MANNER............................10-21 
        10.9.2.2.1 HAZARDS...........................................................10-21 
        10.9.2.2.2 DESIGN AND CONSTRUCTION...........................................10-22 
        10.9.2.2.3 OPERATION AND MAINTENANCE.........................................10-22 
    10.9.3 WORK ON ENERGIZED OR DE-ENERGIZED ELECTRICAL EQUIPMENT....................10-23 
  10.10 REQUIREMENTS FOR SPECIFIC R&D EQUIPMENT......................................10-23 
    10.10.1 CAPACITORS...............................................................10-23 
    10.10.1.1 HAZARDS................................................................10-23 
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      10.10.1.2 DESIGN AND CONSTRUCTION..............................................10-24 
      10.10.1.2.1 AUTOMATIC DISCHARGE DEVICES........................................10-24 
      10.10.1.2.2 SAFETY GROUNDING...................................................10-25 
      10.10.1.2.3 GROUND HOOKS.......................................................10-25 
        10.10.1.2.4 DISCHARGE EQUIPMENT WITH STORED ENERGY IN EXCESS OF 10 JOULES....10-25 
        10.10.1.2.5 FUSING...........................................................10-26 
        10.10.1.3 OPERATION AND MAINTENANCE..........................................10-26 
    10.10.2 INDUCTORS................................................................10-27 
      10.10.2.1 HAZARDS..............................................................10-27 
      10.10.2.2 DESIGN AND CONSTRUCTION..............................................10-27 
      10.10.2.3 OPERATION AND MAINTENANCE............................................10-28 
    10.10.3 ELECTRICAL CONDUCTORS AND CONNECTORS.....................................10-28 
      10.10.3.1 HAZARDS..............................................................10-28 
      10.10.3.2 DESIGN AND CONSTRUCTION..............................................10-29 
      10.10.3.3 OPERATION AND MAINTENANCE............................................10-29 
    10.10.4 INDUCTION AND DIELECTRIC HEATING EQUIPMENT...............................10-29 
      10.10.4.1 HAZARDS..............................................................10-29 
      10.10.4.2 DESIGN AND CONSTRUCTION..............................................10-30 
      10.10.4.3 OPERATION AND MAINTENANCE............................................10-30 
    10.10.5 LASERS AND X-RAY EQUIPMENT...............................................10-30 
      10.10.5.1 HAZARDS..............................................................10-30 
11.0 ELECTRICAL SAFETY DURING EXCAVATIONS.........................................11-1 
  11.1 GENERAL.......................................................................11-1 
  11.2 REGULATIONS, CODES AND REFERENCES.............................................11-1 
  11.3 UTILITIES IDENTIFICATION......................................................11-2 
    11.3.1 CONFIGURATION MANAGEMENT..................................................11-2 
    11.3.2. EXCAVATION PERMIT........................................................11-2 
  11.4 UTILITIES VERIFICATION AND MARKING............................................11-3 
    11.4.1 FIELD LOCATION OF EXCAVATION BOUNDARIES...................................11-4 
    11.4.2 LOCATOR EQUIPMENT SELECTION AND LIMITATIONS...............................11-4 
    11.4.3 LOCATOR OPERATOR TRAINING.................................................11-6 
    11.4.4 FIELD MARKING OF IDENTIFIED UTILITIES.....................................11-6 
  11.5 UTILITIES DISPOSITION.........................................................11-7 
  11.6 WORK CONTROL DURING EXCAVATIONS...............................................11-7 
    11.6.1 SAFETY EQUIPMENT AND PROCEDURES...........................................11-7 
  11.7 THE EXCAVATION PROCESS........................................................11-8 
xv 
    11.7.1 EXCAVATIONS IN CONCRETE WALLS AND SLABS...................................11-8 
    11.7.2 MACHINE OR HAND DIGGING...................................................11-8 
    11.7.3 WORKER PROTECTION.........................................................11-9 
  11.8 AS-BUILT DRAWINGS.............................................................11-9 
12.0 REFERENCES....................................................................12-1 
APPENDIX A DOE MODEL ELECTRICAL SAFETY PROGRAM.......................................A-1 
APPENDIX B ACRONYMS AND DEFINITIONS..................................................B-1 
B.1 ACRONYMS.........................................................................B-1 
B.2 DEFINITIONS......................................................................B-3 
DEFINITIONS APPLICABLE TO 29 CFR 1910 SUBPART S......................................B-3 
DEFINITIONS APPLICABLE TO 29 CFR 1910.269............................................B-17 
DEFINITIONS APPLICABLE TO 29 CFR 1926 SUBPART K......................................B-22 
DEFINITIONS APPLICABLE TO 29 CFR 1926 SUBPART V......................................B-33 
DEFINITIONS APPLICABLE TO SECTIONS 1 THROUGH 10......................................B-37 
APPENDIX C WORK MATRICES – EXAMPLES..................................................C-1 
APPENDIX D REGULATION MATRICES.......................................................D-1 
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