DOE HANDBOOK
ELECTRICAL SAFETY
U.S. Department of Energy AREA SAFT
Washington, D.C. 20585
DISTRIBUTION STATEMENT A. Approved for public release;
distribution is unlimited.
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
xii
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
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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
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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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