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Electrical Standards. MODULE 10. Hazard Brainstorming. Where are electrical hazards on oil and gas well sites?. Statistics. Electrocution: Among most frequent causes of occupational injury death in US 295 fatalities/year; 4309 lost time 1992-2002: 9% decrease

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Hazard brainstorming l.jpg
Hazard Brainstorming

  • Where are electrical hazards on oil and gas well sites?


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Statistics

  • Electrocution: Among most frequent causes of occupational injury death in US

  • 295 fatalities/year; 4309 lost time

  • 1992-2002: 9% decrease

  • Most frequent cause: Overhead power lines


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Factors in Fatal Electrocutions

  • Safe work practices implemented and followed?

  • Adequate/required PPE provided and worn?

  • Lockout/tagout procedures implemented and followed?

  • OSHA, NEC, NESC compliance?

  • Worker and supervisor training adequate?

  • (from NIOSH)


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Types of Electrical Injuries

  • Electrocution (death due to electrical shock)

  • Electrical shock

  • Burns (ugly pictures here)

  • Falls


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Hazard Recognition

  • How can you sense electrical danger?

    • Cannot see, smell, taste, or hear danger

    • Can recognize unsafe conditions


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Electrical Terminology

  • Current – movement of electrical charge

  • Resistance – opposition to current flow

  • Voltage – measure of electrical force

  • Conductors – substances with little resistance to electricity (such as metals)

  • Insulators – substances with high resistance to electricity (such as wood, rubber, glass, & bakelite)

  • Grounding – a conductive connection to the earth (which acts as a protective measure)


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Electrical Shock

  • Received when current passes through body

  • Severity depends on:

    • Path of current through body

    • Amount of current flowing through body

    • Length of time body is in circuit

    • Also: voltage, moisture, heart cycle, health

  • Low voltage is NOT low hazard!


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Dangers of Electrical Shock

  • Currents >75 mA* can cause ventricular fibrillation (rapid, ineffective heartbeat)

    • mA = milliampere = 1/1,000 of an ampere

    • Death within minutes unless a defibrillator is used

    • 75 mA is not much current (a small power drill uses 30 times as much)


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Effects of Current on Body

  • 1 mA: Perception level, slight tingling.

  • 5 mA: Slight shock; not painful.

    • Can usually let go.

    • Involuntary reactions can cause injuries.

  • 6-30 mA: Painful shock

    • Muscular control lost

    • Freezing current or “let-go” range


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Effects of Current on Body

  • 50-150 mA: Extreme pain

    • Respiratory arrest; cannot let go

    • Death possible

  • 1000-4300 mA: Ventricular fibrillation

    • Muscular contraction; nerve damage

    • Death likely

  • 10000 mA: Cardiac arrest

    • Severe burns, probable death


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How Shock Happens

  • Connection between:

    • 2 wires of energized circuit

    • 1 wire of energized circuit and ground

    • Metallic part in contact with energized wire and ground


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Inadequate Wiring Hazards

Wire Gauge

WIRE

  • What happens when a wire is too small to carry the current safely?

    • Overheating

    • Risk of fire or short circuit

    • Fuse acts as sacrificial weak link

    • Fuse too strong? Other parts of the system break first


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29 CFR 1910 and 29 CFR 1926

  • 1910 Subpart S = Electrical

    • Revised 2/14/2007; effective in 180 days

  • 1910 Subpart I = PPE

    • 1910.137 Electrical Protective Devices

  • 1926 Subpart K = Electrical

  • Protect against recognized hazards


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Other Standards

  • NFPA 70E enacted to help meet CFR

    • Revised Subpart S based heavily on 2000 version

    • 2004 version now published

    • OSHA chose which provisions of 70E to adopt


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29 CFR 1910 Subpart S

  • Electrical standards for general industry

  • § 302-308 and 399 updated: PM App. C

  • 5 main groups of standards:

    • Design safety standards § 302-330

    • Safety-related work practices § 331-360

    • Reserved: maintenance, special equipment

    • Definitions: § 399


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1910.302 Electric utilization systems (PM Appendix C)

  • Applicability of regulations

    • By type of installation

    • By installation date


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General

1903.303


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1910.303 (a) Approval

  • Conductors and equipment acceptable only if approved

    • Note: If installation is made in accordance with NEC or ANSI/NFPA it will be deemed in compliance.

    • See definitions


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1910.303(b) Examination, installation, and use of equipment

  • Examination – shall be free of recognized hazards

    • Suitability (check listing/labeling)

    • Other factors listed in regulation

  • Installation and use – by instructions

  • Insulation integrity

  • Interrupting rating (fuses, breakers)


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1910.303(b) Examination, installation, and use of equipment

  • Circuit impedance…

  • Deteriorating agents – water, gases, excessive temperature, corrosives…

  • Mechanical execution of work

    • Close unused openings for protection

    • Conductors racked for safe access

    • Internal parts not contaminated

    • No damaged parts


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1910.303(b) Examination, installation, and use of equipment

  • Mounting and cooling

    • Firmly secured

    • Air circulation; clearance

    • Ventilation openings not obstructed


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1910.303(c) Electrical connections

  • General – dissimilar metals

  • Terminals – connections

  • Splices – correctly performed, insulated


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1910.303(d) Arcing parts

  • Some electrical equipment normally produces arcs, sparks, flames, molten metal

  • Keep isolated from combustible material


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1910.303(e) Marking

  • Manufacturer and ratings must be marked

    • Voltage, current, wattage, etc.

    • Durable markings in environment


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1910.303(f) Disconnecting means and circuits

  • Legibly marked to indicate purpose

    • Unless purpose is evident

  • Durable

  • Able to be locked open

  • Series combination rating = special marking


Subtitles transitions l.jpg

Example of properly labeled

electric service: motors,

disconnects and breakers

Subtitles & Transitions

FOR EXAMPLE…


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1910.303(g) 600 Volts, nominal, or less

  • Space about electric equipment

    • Space, not used for storage

    • Guarded when parts exposed

    • Entrances

    • Illumination

    • Headroom

    • Control boards in dedicated, protected space


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1910.303(g) 600 Volts, nominal, or less

  • Guarding of live parts

    • Live parts  50 volts protected from people

    • Protection from damage

    • Warning signs for unqualified persons


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1910.303(h) Over 600 volts, nominal

  • Enclosure / access control

  • Work space about equipment

  • Entrance and access to work space

  • Working space and guarding



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1910.304(a) Use and identification of grounding conductors

  • Grounded & equipment grounding conductors identifiable & distinguishable

    • Grounded = white or gray

    • Equipment grounding = green, or green with yellow strips, or bare

  • Polarity may not be reversed

  • Grounding devices not used for other purposes


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Polarity

  • Reversed polarity: Neutral (grounded) conductor connected to hot (ungrounded) terminal incorrectly

  • Most common on smaller branch circuits

    • 120 V receptacle outlets

    • Cord- and plug-connected equipment


Subtitles transitions34 l.jpg

Example of properly labeled

electric service: motors,

disconnects and breakers

Subtitles & Transitions

FOR EXAMPLE…


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1910.304(b) Branch circuits

  • Identification of multiwire branch circuits

    • For >1 voltage system in a building

    • ID phase and system

    • Permanently posted at each panelboard


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1910.304(b) Branch circuits

  • Receptacles and cord connectors

    • Grounding type for 15A & 20A circuits

      • Receptacles only on circuits matching voltage and current rating

    • Grounding contacts grounded

      • Except portable / vehicle-mounted generators

      • Except replacement receptacles

    • Grounding contact connected to equipment grounding conductor


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1910.304(b) Branch circuits

  • Receptacles and cord connectors

    • Replacement of receptacles

      • Grounding-type where grounding means exists

      • GFCI where required

      • Options for lack of grounding means

    • Plugs not interchangeable for different voltage, frequency, type of current


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1910.304(b) Branch circuits

  • Ground-fault circuit interrupter (GFCI)

    • Bathroom or rooftops

    • Temporary wiring:

      • Including extension cords

      • If unavailable for less-usual type of receptacle: assured equipment grounding conductor program.


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1910.304(b) Branch circuits

  • Outlet devices

    • Heavy-duty lampholders for >20A

    • Receptacle outlets:

      • Receptacle ampere rating  branch circuit

      • For 2 outlets on branch circuit: Table S-4


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1910.304(b) Branch circuits

  • For 2 outlets on branch circuit: Table S-5

  •  50 A: receptacle  branch-circuit rating

  • Cord connections: Outlet where flexible cords with plugs used


  • 1910 304 c outside conductors 600 volts nominal or less l.jpg
    1910.304(c) Outside conductors, 600 volts, nominal, or less

    • Clearance

    • Power conductors on poles

    • Clearance of open conductors from ground:

      • 10 feet – above sidewalk, grade, platform

      • 12 feet – vehicular traffic

      • 15 feet – truck traffic

      • 18 feet – public streets, alleys, driveways


    1910 304 c outside conductors 600 volts nominal or less42 l.jpg
    1910.304(c) Outside conductors, 600 volts, nominal, or less

    • Clearance from building openings

      • No outer jacket: 3 foot clearance, except above window

      • Not beneath or obstructing openings where materials may be moved

    • Above roofs: 8 ft above, 3 ft from edge

      • Pedestrians? Platform

      • Exceptions for slope, attachment


    1910 304 d location of outdoor lamps l.jpg
    1910.304(d) Location of outdoor lamps

    • Location of outdoor lamps

      • Under energized equipment unless

        • Equipment can be locked out or

        • Clearance/other safeguards adequate


    1910 304 e services l.jpg
    1910.304(e) Services

    • Disconnecting means

      • Main switch disconnects all, indicates on/off

    • Services over 600 volts, nominal

      • Accessible only to qualified; warning signs


    1910 304 f overcurrent protection l.jpg
    1910.304(f) Overcurrent protection

    • 600 volts, nominal, or less

      • Protect conductors and equipment

      • Overcurrent devices readily accessible

        • To employees & building management

        • Not exposed to damage or ignitable material

      • Located/shielded to avoid injury/burns

      • On/off position clearly indicated

      • Vertical: up = on

    • Special rules for over 600 volts


    1910 304 g grounding l.jpg
    1910.304(g) Grounding

    • Systems to be grounded

      • 3-wire DC: neutral conductor

      • 2-wire DC, >50V-300V, with exceptions

      • AC <50V in certain cases

      • AC 50V-1000V (unless exempt) under 4 conditions

      • Exemptions for AC 50V-1000V


    1910 304 g grounding47 l.jpg
    1910.304(g) Grounding

    • Conductor to be grounded

    • Portable and vehicle-mounted generators: frame as grounding electrode

    • Grounding connections

    • Grounding path: permanent, continuous, effective


    Grounding l.jpg
    Grounding

    • One conductor of the circuit intentionally grounded to earth

    • Protects circuit from lightning or other high voltage contact

    • Stabilizes the voltage in the system so “expected voltage levels” are not exceeded under normal conditions


    Grounding49 l.jpg
    Grounding

    • Metal frames / enclosures of equipment grounded by permanent connection or bond

    • Equipment grounding conductor provides path for dangerous fault current to return to ground

    • If damage, corrosion, loosening, etc. impairs continuity, shock and burn hazards will develop


    Grounding path l.jpg
    Grounding Path

    • Shall have capacity to conduct safely any likely fault current.

    • Fault currents may be many times normal currents; can melt points of poor conductivity

    • High temperatures = hazard; can destroy ground-fault path


    1910 304 g grounding51 l.jpg
    1910.304(g) Grounding

    • Supports, enclosures, equipment

      • Exposed non-current-carrying metal parts of cord- and plug-connected equipment

    • Nonelectrical equipment

    • Methods of grounding fixed equipment

    • Grounding of systems and circuits 1000 volts and over (high voltage)


    Ground fault circuit interrupters gfci s l.jpg
    Ground fault circuit interrupters (GFCI’s)

    • GFCI  overcurrent device like a fuse or circuit breaker

    • Designed to sense an imbalance in current flow over the normal path

    • Opens circuit if current in hot and grounded wires differ by 5mA  1mA

    • Must be installed correctly and tested



    1910 305 a wiring methods l.jpg
    1910.305(a) Wiring methods

    • Not applicable to factory-assembled

    • General requirements

      • Metal parts as grounding conductors: effectively bonded

      • Internal insulated grounding conductor for isolated enclosure

      • No wiring systems in ventilation ducts


    1910 305 a wiring methods55 l.jpg
    1910.305(a) Wiring methods

    • Temporary wiring

      • Restricted uses

      • Removed after project completion

      • Requirements for feeders and branch circuits

      • Grounding receptacles

      • No bare conductors or earth returns

      • Disconnecting switches


    1910 305 a wiring methods56 l.jpg
    1910.305(a) Wiring methods

    • Temporary wiring, continued

      • Lamps protected from contact or breakage

      • Flexible cords protected from damage

      • Cables supported


    1910 305 b cabinets boxes and fittings l.jpg
    1910.305(b) Cabinets, boxes, and fittings

    • Conductors entering boxes, cabinets, or fittings

      • Must be protected from abrasion

      • Openings must be closed, with or without wires running through

    • Covers and canopies

      • Metal covers must be grounded

    • >600V: complete, secure, marked enclosure


    1910 305 c switches l.jpg
    1910.305(c) Switches

    • Gravity must not close switches

    • Warning if power may still be available while switch is closed

    • Faceplates where appropriate

    • Grounding


    Switchboards panelboards and enclosures for damp locations l.jpg
    Switchboards, panelboards, and enclosures for damp locations

    • Switchboards and panelboards

      • Switchboards with exposed live parts: in dry places accessible only to qualified persons

      • Panelboards: in enclosures with no live parts on front

      • Switches dead when open

    • Enclosures for wet locations

      • Airspace, weatherproof


    1910 305 f conductors for general wiring l.jpg
    1910.305(f) Conductors for general wiring

    • Insulated unless otherwise permitted

    • Approved type for use

    • Distinguishable by color or other means

      • Grounded

      • Ungrounded

      • Equipment grounding


    1910 305 g flexible cords and cables l.jpg
    1910.305(g) Flexible cords and cables

    • In general much more easily damaged

    • Should not be used if recognized options can be used instead

    • Must be approved for conditions and location

    • Allowable purposes listed


    1910 305 g flexible cords and cables62 l.jpg
    1910.305(g) Flexible cords and cables

    • May not be substituted for fixed wiring

    • May not be run through walls, ceilings, floors, doors, windows

    • May not be attached to buildings

    • May not be concealed in walls, ceilings, floors

    • May not be spliced, except hard service #14

    • Strain relief needed on connections


    Flexible cords acceptable l.jpg
    Flexible cords: Acceptable?

    • Short cord as part of a tool? Yes.

    • Temporary use of extension cord for tool/appliance? Yes.

    • Obviously not temporary? No.

    • Extended over distance to avoid installing fixed outlet? No.


    1910 305 j equipment for general use l.jpg
    1910.305(j) Equipment for general use

    • Lighting fixtures, lampholders, lamps, receptacles

    • Receptacles, cord connectors, and attachment plugs (caps)

    • Appliances

    • Motors

    • Transformers

    • Capacitors

    • Storage batteries



    1910 306 specific purpose equipment and installations l.jpg
    1910.306 Specific purpose equipment and installations

    • Electric signs and outline lighting

    • Cranes and hoists

    • Electric welders—disconnecting means

    • Induction and dielectric



    1910 307 hazardous classified locations l.jpg
    1910.307 Hazardous (classified) locations

    • Classification based on flammable vapors, liquids, gases, combustible dusts or fibers

    • Each area considered individually

    • Classified by classes and divisions or zones

    • Documentation available for users, designers, installers, maintainers of electric equipment


    1910 307 hazardous classified locations69 l.jpg
    1910.307 Hazardous (classified) locations

    • Definitions of classes and divisions in 1910.399, Definitions

      • Class I: flammable gases/vapors; explosive or ignitable mixtures

      • Class II: combustible dust

      • Class III: easily ignitable fibers or flyings; not likely to be in suspension

      • Division 1 & 2 for each; Zones 0-2 for Class I


    1910 307 c electrical installations l.jpg
    1910.307(c) Electrical installations

    • Equipment must be one of these:

      • Intrinsically safe

      • Approved for hazardous (classified) location

        • Approved and marked for class and properties of material present

      • Safe for hazardous (classified) location

        • NFPA 70 referenced


    Conduits and equipment l.jpg
    Conduits and equipment

    • Conduits: threaded, wrench-tight or bonding jumper

    • Equipment in Division 2 locations:

      • Division 1 approved equipment = OK

      • General-purpose equipment OK if demonstrably not a source of ignition


    1910 307 f protection techniques l.jpg

    Explosionproof apparatus

    Dust ignitionproof

    Dust-tight

    Purged and pressurized

    Nonincendive circuit

    Nonincendive equipment Nonincendive component

    Oil immersion

    Hermetically sealed

    Other protection techniques

    1910.307(f) Protection techniques


    1910 307 g class i zone 0 1 and 2 locations l.jpg
    1910.307(g) Class I, Zone 0, 1, and 2 locations

    • Zone = alternative to divisions for Class 1

    • Classified by chemical properties and likelihood of combustible atmosphere

    • Proper installation of conduit & equipment to avoid sparks in flammable/combustible atmosphere

    • Protection techniques for certain zones


    1910 307 g class i zone 0 1 and 2 locations74 l.jpg
    1910.307(g) Class I, Zone 0, 1, and 2 locations

    • Special precaution: PE must classify areas and specify equipment

    • Listing and marking:

      • Listed for Zone 0 = OK for Zone 1-2

      • Listed for Zone 1 = OK for Zone 2

      • (For same gas or vapor)

      • Marking requirements & exemption

    • More information in NFPA 70



    Special systems l.jpg

    Special Systems

    1910.308


    1910 308 special systems l.jpg
    1910.308 Special systems

    • Systems over 600 volts, nominal

    • Emergency power systems

    • Remote control, signaling, and power-limited circuits

    • Fire alarm systems

    • Communications systems

    • Solar photovoltaic systems

    • Integrated electrical systems


    Definitions l.jpg

    Definitions

    1910.399


    1904 399 definitions l.jpg
    1904.399 Definitions

    • New version supersedes older version in CFR book


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    References for Further Information

    1910 SUBPART S APPENDIX A


    1910 subpart s appendix a l.jpg
    1910 Subpart S Appendix A

    • Nonmandatory references aid in understanding

    • Not a substitute for compliance with CFR

    • Appendices B and C removed



    1910 331 scope l.jpg
    1910.331 Scope

    • Qualified persons (who have training in avoiding the electrical hazards)

    • Unqualified persons (with little or no such training)

    • Working on or near:

      • Premises wiring

      • Wiring for connection to supply

      • Other wiring

      • Vehicles excluded


    1910 332 training l.jpg
    1910.332 Training

    • Scope: employees with electric shock risk not reduced to safe level by installation requirements

    • Training content:

      • Work practices for job assignments

      • 1910.331-335 and others necessary

      • Qualified vs. unqualified

    • Classroom or on-the-job; risk based


    Employees to be trained l.jpg
    Employees to be Trained

    • Electricians and welders

    • Any others if:

      • work they do or supervise

      • comes close enough to exposed parts of electric circuits 50V

      • for hazard to exist



    1910 333 a 1 deenergized parts l.jpg
    1910.333 (a)(1) Deenergized parts

    • Live parts deenergized before employee works on or near them:

      • Unless infeasible or causes greater hazard

      • <50V not deenergized if no increased exposure to burns or arcs

      • Examples in CFR

    • If not deenergized, other work practices must protect employees


    1910 333 b working on or near exposed deenergized parts l.jpg
    1910.333(b) Working on or near exposed deenergized parts

    • If not locked out or tagged out, treated as energized

    • Lockout/tagout rules followed in order

    • 1910.147 provisions may also be OK

    • Written copy of procedures available


    1910 333 b working on or near exposed deenergized parts89 l.jpg
    1910.333(b) Working on or near exposed deenergized parts

    • Lockout/tagout steps in section (2):

      • Deenergizing equipment

      • Application of locks and tags

      • Verification of deenergized condition

      • Reenergizing equipment after work


    1910 333 c working on or near exposed energized parts l.jpg
    1910.333(c) Working on or near exposed energized parts

    • Only qualified persons may work on energized electric circuit parts

    • For work near overhead lines:

      • Lines deenergized and grounded, or

      • Other protective measures provided


    Working near overhead power lines l.jpg
    Working near overhead power lines

    • Unqualified person near energized lines

      • Person and longest conductive object not closer than 10 ft, + 4 in/10kV above 50kV

      • For elevated or ground work

    • Qualified person:

      • Closer approach only with insulation

      • Table S-5: distance varies by voltage

    • Equipment: same distance as unqualified


    Working near overhead power lines92 l.jpg
    Working near overhead power lines

    • Equipment: same distance as unqualified, with exceptions:

      • In transit, structure lowered: 4 ft +4 in/10kV

      • Insulating barriers, not part of vehicle

      • Aerial lift, insulated, with qualified person

      • Ground employees may not contact equipment without protection or distance

      • Employees may not stand at grounding location when line contact possible


    1910 333 c working on or near exposed energized parts93 l.jpg
    1910.333(c) Working on or near exposed energized parts

    • Illumination must allow safe work – may not reach blindly in

    • Confined space work requires protective insulation & secured doors

    • Conductive materials: prevent contact with energized parts

    • Portable ladders: nonconductive siderails


    1910 333 c working on or near exposed energized parts94 l.jpg
    1910.333(c) Working on or near exposed energized parts

    • Conductive apparel not worn, or insulated

    • Housekeeping near live parts:

      • Requires safeguards

      • No conductive cleaning materials, including liquid solutions

    • Interlocks may only be defeated temporarily by qualified person



    1910 334 a portable electric equipment l.jpg
    1910.334(a) Portable electric equipment

    • Handled in a manner to not cause damage

    • Cords not used to raise/lower equipment

    • Cords not stapled or hung in ways that damage insulation


    1910 334 a portable electric equipment97 l.jpg
    1910.334(a) Portable electric equipment

    • Visual inspection required before use:

      • Portable cord / plug connected equipment

      • Extension cords

      • For external defects and evidence of internal damage

      • If not exposed to damage, only when relocated

    • Defect or damage: remove, do not use until repaired and tested

    • Plug and receptacle checked for compatibility


    1910 334 a portable electric equipment98 l.jpg
    1910.334(a) Portable electric equipment

    • Grounding type equipment: ground must be maintained

    • Conductive work locations (e.g. wet) require approved equipment and cords

    • Connecting plugs:

      • Never plug or unplug live equipment with wet hands

      • Protect hands from conductive path (water)

      • Locking connectors: properly secured


    1910 334 b electric power and lighting circuits l.jpg
    1910.334(b) Electric power and lighting circuits

    • Never reenergize a blown fuse

    • Never reenergize a circuit breaker until it is safe (Overload or fault?)

    • Never modify overcurrent protection beyond § 304 requirements


    1910 334 c and d l.jpg
    1910.334(c) and (d)

    • Test instruments and equipment

      • Only qualified persons may test electric circuits or equipment

      • Test instruments must be visually inspected

      • Must be rated for circuits & environment

    • Occasional use of flammable and ignitable materials: Do not use equipment that could ignite them



    1910 335 a use of protective equipment l.jpg
    1910.335(a) Use of protective equipment

    • Personal protective equipment

      • Must be provided with & use equipment

      • Maintained, inspected, and tested

      • Insulating material protected

      • Nonconductive head protection

      • Eye or face protection for arcs, flashes, flying objects from explosions

    • Insulated tools or handling equipment

    • Shields, insulation for heating/arcing


    1910 335 b alerting techniques l.jpg
    1910.335(b) Alerting techniques

    • Techniques to warn and protect employees:

      • Safety signs and tags

      • Barricades

      • Attendants


    Relevant standards outside 29 cfr 1910 l.jpg
    Relevant Standards Outside 29 CFR 1910

    • 29 CFR 1926 Subpart K: construction

    • API RP 54

      • Section 9.14 Generators, Motors, and Lighting

      • Section 10: Drilling and Well Servicing Rig Electrical Systems

    • API RP 14F for offshore wiring

    • API RP 500 and 505: area classification


    Clues that electrical hazards exist l.jpg
    Clues that Electrical Hazards Exist

    • Tripped circuit breakers or blown fuses

    • Warm tools, wires, cords, connections, or junction boxes

    • GFCI that shuts off a circuit

    • Worn or frayed insulation around wire or connection


    Subtitles transitions106 l.jpg

    Example of properly labeled

    electric service: motors,

    disconnects and breakers

    Subtitles & Transitions

    FOR EXAMPLE…


    Subtitles transitions107 l.jpg

    Example of properly labeled

    electric service: motors,

    disconnects and breakers

    Subtitles & Transitions

    FOR EXAMPLE…


    Subtitles transitions108 l.jpg

    Example of properly labeled

    electric service: motors,

    disconnects and breakers

    Subtitles & Transitions

    FOR EXAMPLE…


    Subtitles transitions109 l.jpg

    Example of properly labeled

    electric service: motors,

    disconnects and breakers

    Subtitles & Transitions

    FOR EXAMPLE…


    Subtitles transitions110 l.jpg

    Example of properly labeled

    electric service: motors,

    disconnects and breakers

    Subtitles & Transitions

    FOR EXAMPLE…


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    Example of properly labeled

    electric service: motors,

    disconnects and breakers

    Subtitles & Transitions

    FOR EXAMPLE…


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    OSHA Resources

    • Pub 3075 Controlling Electrical Hazards

    • Small Business Handbook section

    • Inspection Procedures

      • Electrical Safety-Related Work Practices -- Inspection Procedures and Interpretation Guidelines


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    Interpretations

    • Training requirements for employees who perform non-electrical work on electrical equipment

    • Qualifications for resetting circuits or replacing fuses; electrical enclosures must be approved

    • Use of compressed air above 30 p.s.i. for cleaning purposes; nonmetallic-sheathed cable for temporary wiring