z - electrical - wiring methods, components(a) (rl-vpp web)

7/22/2019 Z - Electrical - Wiring Methods, Components(a) (RL-VPP Web)

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Electrical Wiring Methods,Components and Equipment for

General Use

Approved for Public Release;

Further Dissemination Unlimited


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At the completion of this unit you shall be able to:

1. Utilize section Z of the Safety and HealthHazard Inspection Program Checklist toidentify compliant and non-compliant safety

behaviors.2. Identify areas of concern requiring immediate

action to mitigate or prevent a possible injury.

Please use Slide Show to properly view this

presentation!


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Lets start with adiscussion of

Electrical Safety.


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Whenever you work with electrical devices thereis a risk of electrical hazards, especially

electrical shock. Risks are increased atmaintenance and construction sites becausemany jobs involve electric power tools.

Coming in contact with an electrical voltage cancause current to flow through the body, resulting

in electrical shock and burns. Serious injury oreven death may occur.

Electricity has long been recognized as aserious workplace hazard, exposing employeesto electric shock, electrocution, burns, fires, and

explosions. In 1999, for example, 278 workersdied from electrocutions at work, accounting foralmost 5 percent of all on-the-job fatalities thatyear, according to the Bureau of LaborStatistics. What makes these statistics moretragic is that most of these fatalities could have

been easily avoided.


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When an electrical shock enters the

body it may produce different typesof injuries. Electrocution results ininternal and external injury to bodyparts or the entire body oftenresulting in death. After receiving a

jolt of electricity all or part of thebody may be temporarily paralyzedand this may cause loss of grip orstability. A person may alsoinvoluntarily move as a result of

receiving an electrical shock,resulting in a fall. Internal or externalburns may result from contact withelectricity.


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For this reason weinspect and verifythe safety of our

electricalequipment in ouroffices, shops, and

posts.


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Section Z deals withthe Electrical wiringmethods,

components andequipment forgeneral use.


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This sectionconsists of up to 13items.

Lets look at thesemore closely.


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1. Junction, switch, and outlet boxes have all openings covered.

2. Extension cords are not used as a substitute for permanent, fixed wiring.

3. Flexible cords and cables are in good condition and properly routed to prevent physicaldamage and eliminate tripping hazards.

4. Multi-outlet power strips/surge protectors properly connected (no daisy chain).

5. 36-inch working space is maintained in front of electrical panels. Panel schedules areclearly legible and up-to-date.*

6. Electrical disconnects are labeled to identify the equipment it controls, or so located thatits purpose is evident.*

7. Insulation on wiring is in good condition.

8. Electrical equipment installed or used in wet or hazard class locations is approved forsuch use. *

9. Space heaters are approved by a Nationally Recognized Testing Laboratory (NRTL). *

10. Warning signs and/or physical barriers are used to keep unauthorized employees a safedistance from exposed energized electrical equipment/parts above 50 volts. *

11. Electrical rooms or enclosures containing live parts/conductors operating at greater than600 volts are locked and labeled Danger High Voltage. *

12. Holes through which conductors pass will not cause damage to conductor.


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Junction, switch, andoutlet boxes aredesigned to have their

covers on them andany other holes thatcould allow a finger

to contact liveelectrical partsguarded.


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Junction, switch, andoutlet boxes are designedto have their covers onthem and any other holesthat could allow a fingerto contact live electricalparts guarded.

Underneath these coversare live electrical partsthat can cause injury.


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A compliant ratingwould indicatethat all holes weresealed and allcovers in place.


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1. Junction, switch, and outlet boxes have all openings covered. A non compliant

rating would indicatethat the covers weremissing, broken, or

that cable holes(knockouts) weremissing that couldallow contact withexposed electricalparts.


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2. Extension cords are not used as a substitute for permanent, fixedwiring.

Extension cords are found in manywork locations at this project. Using anextension cord is convenient, but if

misused, can create unsafeconditions. Potential hazards includefires from overloaded cords, electricalshock from worn or damaged cords,

and trip and fall accidents fromunsecured cords. According to theNational Electrical Safety Foundation,extension cords should be used only ona temporary basis.


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Generally, if an extension cordis plugged in for >90 days it isconsidered permanent wiringand as such is a violation of theelectrical code and ProjectPolicy.


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A compliant rating onthis item wouldindicate that allextension cords foundwere not being usedas a permanent

wiring methods.


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A non compliantrating would indicatethat the extensioncord had been therefor some time andwas being used in lieu

of permanent wiringmethods.


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3. Flexible cords and cables are in good condition and properlyrouted to prevent physical damage and eliminate tripping

hazards.

Extension cords allow us toprovide power to the toolsand equipment that have

cords that are too short.Unfortunately cords on theground can create trippinghazards as well as create anopportunity for failure of

the electrical sheathing(insulation) of the cord. For this reason we require

that cords be routedproperly.


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hazards.

A compliant ratingwould indicate that

the extension cordswere protected fromdamage and were not

creating a trippinghazard.


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hazards.

Non compliant ratingwould indicate that thecords were located wherethey could be damagedor they could trip

someone.


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4. Multi-outlet power strips/surge protectors properly connected(no daisy chain).

The supply of readilyavailable electrical outlets isinadequate in some buildings,

especially older ones. To meetpower supply needs,extension cords or surgeprotected power strips are

often interconnected, or daisychained, to readily providemore outlets and/or to reachgreater distances.


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Another common solutionis to create a mixed daisychain, interconnectingextension cords and power

strips. However,interconnecting thesedevices is a violation ofOccupational Safety andHealth Administration(OSHA) regulations and theNational Electrical Codebecause doing so can causethem to become overloaded,leading to their failure anda possible fire.


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A compliant rating wouldindicate that the powerstrips in use were plugged

directly into anpermanently wiredreceptacle, did not connectto another strip or surgesuppressors or use anextension cord.


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A non compliant ratingwould indicate that thepower strips/suppressors

were daisy chained.


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A non compliant ratingwould indicate that thepower strips/suppressors

were daisy chained.

Also, it would indicate thatthe power strips werent

being used correctly inother ways as well. Multiple issues here, but the

strips are not being used iawwith the manufacturersinstructions!


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5. 36-inch working space is maintained in front of electrical panels.Panel schedules are clearly legible and up-to-date.

The minimum requirements forboth access and working space forelectrical equipment used on

circuits 600 volts nominal or lessare 30 inches wide and 3 feet deep.

Equipment examples includepanelboards, switches, circuit

breakers, controllers, and controlson heating and air-conditioningequipment.

This area cannot be used for

storage.


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Also included in this itemis the requirement thateach panel clearly state

what circuits are fed byeach breaker. This iscalled the schedule.

Schedule


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A compliant rating wouldindicate that the access to thesedisconnects, panel boards, and

breaker boxes were clear of non-electrical equipment.

These would include boxes,brooms, garbage cans, chairs, etc.

Also the schedule was legible andup to date showing the loads thatwere served by each breaker.


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A non compliant rating wouldindicate that the access to thesedisconnects, panel boards, and

breaker boxes were not clear ofnon-electrical equipment or theschedule was missing or wasillegible.


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6. Electrical disconnects are labeled to identify the equipment itcontrols, or so located that its purpose is evident.

The purpose of this item isto ensure that equipmentdisconnects are eitherclearly marked as to theequipment they serve or itis obvious which equipmentthey serve. An example ofobvious would be adisconnect for a machinethat is mounted on themachine or the cableconnecting the disconnect isobviously going into onlythat machine.


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A compliant rating wouldindicate that thedisconnects were eithermarked for the equipment

they served or they wereobvious in their locationand function.


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A non compliant ratingwould indicate that thedisconnects were eithermarked for the equipment

they served or they wereobvious in their locationand function.

No label???


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The purpose of this item isto check on the condition ofthe insulation on wires ofequipment being used.

It is not intended as an fullscope electrical inspectionbut rather a visual check on

the condition of theelectrical cordage beingused.


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Obviously if you observea wiring system such asthis youll want to the letthe facility manager andyour safety professionalsknow as soon as possible.


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Generally, you need tolook for damaged cords;


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modified plugs


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modified plugs

obvious improper wiringmethods


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modified plugs

obvious improper wiringmethods

illegal 3 prong adaptors(suicide plugs).


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If you find that the cordageand electrical installationsare in good condition thenyou would rate the item as

compliant. Otherwise you would need

to rate the item as noncompliant or less, ensure that

the comment section wasfilled out, and in all theexamples given ensure thatthe facility manager wasinformed and took action

immediately.


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8. Electrical equipment installed or used in wet or hazard classlocations is approved for such use.


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Electrical equipment needsto be approved and ratedfor the environment it islocated in.

Major incidents havehappened in facilities wherethe equipment was eithernot approved for use in thatenvironment or haddegraded to where it wasnot longer safe.

Electrical Wiring Methods, Components

and Equipment for General Use8. Electrical equipment installed or used in wet or hazard class locations is

approved for such use. *


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When we talk aboutelectrical equipment in wetareas we mean equipment

that will not short to groundor if there is a problem withthe device it is designedwith safeguards to protect

the operator of theequipment from shock.These protections includeGFCIs, double insulation,

and water proof/weatherroof installations.


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We also are concerned thatthe electrical equipment isappropriate for any hazardsthat may be present. TheCodes and Standards haverequirements that electricalequipment in locations ofexplosive gas, dust, or

liquids but be rated for thatpurpose.

Imperial Sugar FactoryGeorgia, after recent sugardust explosion.


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A compliant rating wouldindicate that the electricalequipment was installedcorrectly and was for theenvironment it was locatedin.


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A compliant rating wouldindicate that the electricalequipment was installedcorrectly and was for theenvironment it was locatedin.

A non compliant ratingwould indicate that theelectrical equipment wasnot approved for thatlocation.

An outside receptacle not

protected from the weather.


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9. Space heaters are approved by a Nationally Recognized TestingLaboratory (NRTL).

Space heaters are used foraugmentation of existingheating systems in many ofour buildings. Theseheaters are of manydifferent types and usemany different types ofenergy to create heat. Of

concern in this item are thesafety of electric spaceheaters that are used by ourpersonnel.


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If these heaters are not usedproperly or are not of thecorrect and listed type thena fire can happen.

The photo on the rightshows a space heater thathad combusible materialplaced to close to it.Subsequently a fatal fireoccurred.


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Must have a tip-overshutdown feature. If aspace heater is knocked

over, the unit mustautomatically shut off.


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Must be UL(UnderwritersLaboratory), or other

Nationally recognizedtesting laboratoryapproval (NRTL), andmust be labeled

accordingly.


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A compliant ratingwould indicate that thespace heater had met

these requirements andwas being safely used.


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A non compliantrating would

indicate that theheater was notlisted or was not in

a safe condition. Flammables within 3


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10. Warning signs and/or physical barriers are used to keepunauthorized employees a safe distance from exposed energized

electrical equipment/parts above 50 volts.

The purpose of this item isto ensure that personnel areprotected from hazards ofexposed electrical parts (>50 VAC to ground) duringboth maintenance andnormal operations.

There are two types ofhazards we guard against.


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electrical equipment/parts above 50 volts. The first is to guard against the possibility

of arc flash duringmaintenance/operations of the equipment

with their covers off. Flash Protection Boundary distance from

an arc source within which an employeemay receive a seconddegree burn from an

electrical arc flash The Flash Protection Boundary is 4 feet for

energized electrical equipment up to 600volts unless otherwise calculated.


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Access into this barrier requires thatonly qualified persons wearing the

prescribed arc flash PPE mayapproach.

The perimeter of this area must bemarked so that no unsuspecting

employee may enter the area and be atrisk.


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electrical equipment/parts above 50 volts. The second type of electrical hazard

we try to protect against is thepossibility of electrical shock.

Guarding is provided by locatingthe energized equipment in rooms,vaults, enclosures, etc, onlyaccessible to qualified persons.

We place components in enclosures(panels) that require tools to accessthe live parts.


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electrical equipment/parts above 50 volts. We also can protect exposed live

electrical equipment by location on asuitable balcony, gallery, or platformand arranged so as to excludeunqualified persons.

We also can guard by elevation aminimum of 8 feet or more above thefloor or other working surface.

For exposed movable conductors (likeon cranes) we require a minimum of 10feet elevation to protect workers.


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electrical equipment/parts above 50 volts. In order to protect personnel from

accidental shock there is a 3 footapproach distance from exposed

(unguarded) electrical components. Thisarea is restricted to only qualifiedpersons or persons under the directsupervision of qualified person.

This is called the limited approachboundary (LAB).

If the conductor is an exposed movableconductor then the LAB is 10 feet.


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A compliant rating wouldindicate that either there

were no exposed energizedelectrical wires, there weresufficient barriers, or therewas sufficient boundaries in

place to prevent accidentalcontact.


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electrical equipment/parts above 50 volts. A non compliant rating would

indicate there were conditions thatcould lead to accidental contact

with live electrical conductors.

Multiple hazards!!


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11. Electrical rooms or enclosures containing live parts/conductorsoperating at greater than 600 volts are locked and labeled Danger

High Voltage. This item is to ensure that nonqualified personnel do nothave access to intermediate orhigh voltage equipment (>600VAC)

This is not a requirement forlower voltage systems (


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High Voltage. A compliant rating would

indicate that these locationswere locked.


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High Voltage. A compliant rating would

indicate that these locationswere locked.

Note these locations alsohave to be marked asDANGER High Voltageas well.


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High Voltage.

A non compliant ratingwould indicate that these

locations were not lockedand were accessible to nonqualified personnel.

Open Door/Unlocked/Unattended


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12. Holes through which conductors pass will not cause damage toconductor.

This item is to ensure thatcords and wires goingthrough holes in desks,walls, panels, etc. are

protected from cutting andabrasion from sharp edges.

Grommets (a desk grommetshown here), stuffing tubes

and other devices are usedto protect electricalconductors.


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A compliant rating wouldindicate that the conductorswere protected from cuttingand abrasion.


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A non compliant ratingwould indicate that theconductors were notprotected from cutting and

abrasion.


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If at any time you have

any questions abouthow to fill out the formor about the items onthe form please contact

your project OS&Hgroup.


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Thank you for your timeand desire to help us have

a safer workplace

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