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Electrical SafetyElectrical Safety
AGENDAAGENDA
– Electricity's Beginning OnsiteElectricity's Beginning Onsite– Temporary Power/LightingTemporary Power/Lighting– GFCI vs. Circuit BreakerGFCI vs. Circuit Breaker– Power ToolsPower Tools– Safe Guarding Permanent PowerSafe Guarding Permanent Power– Energized WorkEnergized Work
Electricity’s Beginning Electricity’s Beginning OnsiteOnsite
Electricity's Beginning On SiteElectricity's Beginning On Site
The First Point of inspecting an electrical The First Point of inspecting an electrical system is at it point of origin system is at it point of origin (1926.404(c))(1926.404(c))
Ensure Overhead Lines (insulated) will Ensure Overhead Lines (insulated) will be more than 8 feet away from future or be more than 8 feet away from future or existing buildings (NEC 225-19).existing buildings (NEC 225-19).
Electricity's Beginning On SiteElectricity's Beginning On Site
Ensure Service entrance lines have Ensure Service entrance lines have appropriate clearance distances from the appropriate clearance distances from the ground (NEC 225-18) ground (NEC 225-18) – 10’ sidewalks, accessible to pedestrians only, 10’ sidewalks, accessible to pedestrians only,
ect. ect. – 12’ over residential property and driveways no 12’ over residential property and driveways no
subject to truck trafficsubject to truck traffic– 15’ Same as 12’ but when voltage exceeds 300V15’ Same as 12’ but when voltage exceeds 300V– 18’ Over public streets and areas subject to 18’ Over public streets and areas subject to
truck traffictruck traffic
Electricity's Beginning On SiteElectricity's Beginning On Site
Ensure the connection at the Ensure the connection at the weatherhead is secure and seems weatherhead is secure and seems capable of safely holding.capable of safely holding.
Ensure underground services are Ensure underground services are protected from damage (NEC 230-49 protected from damage (NEC 230-49 refers to table 300-5)refers to table 300-5)
Temporary PowerTemporary Power
Temporary PowerTemporary Power
After the Service entrance has After the Service entrance has been confirmed as safe the next been confirmed as safe the next step is to follow the conduits to step is to follow the conduits to the first Panelthe first Panel
Temporary PowerTemporary Power Ensure Appropriate warnings and Labels Ensure Appropriate warnings and Labels
are in placeare in place– Flash Hazard (NEC 110.16)Flash Hazard (NEC 110.16)– Danger High Voltage (110.34 (c))Danger High Voltage (110.34 (c))– For rooms and other guarded locations – For rooms and other guarded locations –
Qualified Persons only (NEC 110.27(c))Qualified Persons only (NEC 110.27(c))– Reference Index of NEC:Reference Index of NEC:
• Labels Required and Warning SignsLabels Required and Warning Signs
Temporary PowerTemporary Power
Open the Panel and ensure:Open the Panel and ensure:– That no energized parts are That no energized parts are
accessible (1926.405(d))accessible (1926.405(d))– Circuits are identified for Circuits are identified for
disconnecting purposes disconnecting purposes (1926.403(h))(1926.403(h))
Verify that all circuits are in the Verify that all circuits are in the “on” position. “on” position.
This is especially important in This is especially important in verifying that an effective verifying that an effective lockout/tagout system is in place.lockout/tagout system is in place.
If a circuit is off, ask and verify If a circuit is off, ask and verify why???why???
Temporary PowerTemporary Power
Temporary PowerTemporary Power
Ensure that access to electrical Ensure that access to electrical rooms and panels are limited to rooms and panels are limited to qualified persons NEC 110-27qualified persons NEC 110-27
Temporary PowerTemporary Power
Ensure Temporary Power (Plugs) Ensure Temporary Power (Plugs) are separate circuits from are separate circuits from Temporary Lighting. (1926.405(a)Temporary Lighting. (1926.405(a)(2)(ii)(c))(2)(ii)(c))
Temporary LightsTemporary Lights All bulb types must be protected from All bulb types must be protected from
accidental contact or breakage at all accidental contact or breakage at all times. (1926.405(a)(2)(ii)(E))times. (1926.405(a)(2)(ii)(E))
– Any empty light socket that does not Any empty light socket that does not contain a bulb exposes energized parts contain a bulb exposes energized parts that can be a violation of 1926.416(a) or that can be a violation of 1926.416(a) or 1926.403(i)(2) exceptions listed A-D1926.403(i)(2) exceptions listed A-D
Temporary LightsTemporary Lights
Temporary Lights are to be installed so Temporary Lights are to be installed so as to protect the conductors from as to protect the conductors from damagedamage– Hang fixtures as designed and not Hang fixtures as designed and not
with conductive material. with conductive material. 1926.405(a)(2)(ii)(f)1926.405(a)(2)(ii)(f)
– Flexible cords are permissible if Flexible cords are permissible if protected correctly. 1926.405(a)(2) – protected correctly. 1926.405(a)(2) – (ii)(I) and (ii)(J)(ii)(I) and (ii)(J)
GFCI vs. Circuit GFCI vs. Circuit BreakersBreakers
GFCI vs. Circuit BreakersGFCI vs. Circuit Breakers
GFCI SpecificationsGFCI Specifications– Will trip at 4-6mANOTE: A Ground Fault Circuit Interrupter (GFCI) limits the duration of an electrical shock to a period considered safe for healthy people. It does not prevent electric shock. This device does not protect against electric shock due to contact with both circuit conductors or a fault in any wiring supplying this device.
GFCI vs. Circuit BreakersGFCI vs. Circuit Breakers
Required to protect all Temporary Power circuits.– Extension Cords become “temporary
Power circuits” when plugged into permanent Receptacles.
GFCI vs. Circuit BreakersGFCI vs. Circuit Breakers
Circuit breakers are Overcurrent protection devices which is one part of the overcurrent protection system.
Breaker/Fuse – Wire – Device
GFCI vs. Circuit BreakersGFCI vs. Circuit Breakers
GFCI for Portable Generators– Required at 5KW (LOI 8/24/77)– Frame not required to be grounded NEC
250.34 and 1926.404(f)(3) GFCI Circuit Breakers
– For any VoltageFor any Voltage
Extension CordsExtension Cords
Extension CordsExtension Cords
NEC References:NEC References:– 240.5 Overcurrent Protection240.5 Overcurrent Protection
– Table 400.5(a) Flexible Cord allowable ampsTable 400.5(a) Flexible Cord allowable amps
– Or 240.5(b)(3) extension cords considered protected Or 240.5(b)(3) extension cords considered protected when applied within the extension cord listing when applied within the extension cord listing requirementsrequirements
Extension CordsExtension Cords
guide for cords less than 50 ft. guide for cords less than 50 ft. #12 gauge - 1920 watts - 16 amps – large bench saws #12 gauge - 1920 watts - 16 amps – large bench saws #14 gauge - 1440 watts - 12 amps - portable power #14 gauge - 1440 watts - 12 amps - portable power
saws, routers saws, routers #16 gauge - 840 watts - 7 amps –Belt Sanders#16 gauge - 840 watts - 7 amps –Belt Sanders , recip saws , recip saws #18 gauge - 600 watts - 5 amps - drills, small sanders#18 gauge - 600 watts - 5 amps - drills, small sanders
Extension CordsExtension Cords
120 V Extension Cord Maximum Ampacity
Extension Extension Cord Length
Cord Size 200' 150' 100' 50'
14 2.75A 3.7A 5.5A 11A
12 4.25A 5.7A 8.5A 17A
10 7A 9A 14A 25A
Extension CordsExtension Cords
– Prohibited Uses 1926.405(g)(1)(iii)Prohibited Uses 1926.405(g)(1)(iii)– as a substitute for the fixed wiring of a structureas a substitute for the fixed wiring of a structure– Where run through holes in walls, ceilings, or floors.Where run through holes in walls, ceilings, or floors.– Where run through doorways, windows, or similar Where run through doorways, windows, or similar
openings not protected from pinch points.openings not protected from pinch points.– Where attached to building surfaces or concealed Where attached to building surfaces or concealed
behind walls, ceilings, or floorsbehind walls, ceilings, or floors
Extension CordsExtension Cords
– Shall be designed for hard or extra-hard usage.Shall be designed for hard or extra-hard usage.– 1926.405(a)(2)(ii)(J)1926.405(a)(2)(ii)(J)– NEC Table 400.4NEC Table 400.4– Common Examples include – S, SO, SJ, SJTCommon Examples include – S, SO, SJ, SJT
– Shall be used only in continuous lengths Shall be used only in continuous lengths without spice or tap. 1926.405(g)(2)(ii)without spice or tap. 1926.405(g)(2)(ii)– #12 or larger may be repaired if spice retains #12 or larger may be repaired if spice retains
insulation and usage characteristicsinsulation and usage characteristics
Extension CordsExtension Cords
– NEC 400.21 Insulation shall not be less than NEC 400.21 Insulation shall not be less than specified specified – If a visible amount of insulation has been removed it If a visible amount of insulation has been removed it
is in need removal or repairis in need removal or repair
Power ToolsPower Tools
Power ToolsPower ToolsFrom NFPA 70E 110.9(B)(1)From NFPA 70E 110.9(B)(1)
Portable equipment must be handled in a Portable equipment must be handled in a manner which will not cause damage. Flexible manner which will not cause damage. Flexible electric cords connected to equipment may not electric cords connected to equipment may not be used for raising or lowering the equipment. be used for raising or lowering the equipment.
Flexible cords may not be fastened with staples Flexible cords may not be fastened with staples or otherwise hung in such a fashion as could or otherwise hung in such a fashion as could damage the outer jacket or insulation. damage the outer jacket or insulation.
Power ToolsPower ToolsFrom NFPA 70E 110.9(B)(3)From NFPA 70E 110.9(B)(3)
Portable cord and plug connected equipment Portable cord and plug connected equipment and flexible cord sets (extension cords) shall be and flexible cord sets (extension cords) shall be visually inspected before use on any shift for visually inspected before use on any shift for external defects:external defects:– Loose parts Loose parts – Deformed or missing pins Deformed or missing pins – Damage to outer jacket or insulation Damage to outer jacket or insulation – Evidence of possible internal damageEvidence of possible internal damage
Power ToolsPower Tools
If there is a defect or evidence of If there is a defect or evidence of damage to any electrical tools or damage to any electrical tools or equipment…equipment…
Take it Out of ServiceTake it Out of Service Imagine an employee dies while Imagine an employee dies while
using the Power tool that using the Power tool that youyou repaired.repaired.
Fatality at Trussville HighFatality at Trussville High
Ladders….Ladders….– Portable ladders must Portable ladders must
have non-conductive side have non-conductive side rails if they are used where rails if they are used where a workers or the ladder a workers or the ladder could contact exposed could contact exposed energized parts. energized parts.
– Keep all ladder parts at Keep all ladder parts at least 10 feet away from least 10 feet away from overhead power linesoverhead power lines
Controlling Permanent Controlling Permanent PowerPower
Through an effective Lock out / Tagout Through an effective Lock out / Tagout SystemSystem
Controlling Permanent Controlling Permanent PowerPower
Prior to Energizing Permanent Prior to Energizing Permanent Power There are a few things to Power There are a few things to checkcheck
Controlling Permanent Controlling Permanent PowerPower
Check Main Switch Gear for Check Main Switch Gear for Empty ConduitsEmpty Conduits– Why are they empty?Why are they empty?– Are they capped?Are they capped?– Will Duct Tape work?Will Duct Tape work?
Controlling Permanent Controlling Permanent PowerPower
Once the gear is energized there Once the gear is energized there should be no reason to re-enter.should be no reason to re-enter.– Re-entering energized gear would Re-entering energized gear would
require a scheduled “shut-down” with require a scheduled “shut-down” with local utility company. local utility company.
– Or Gear must be designed to shut-down Or Gear must be designed to shut-down in sections.in sections.
Controlling Permanent Controlling Permanent PowerPower
Check to Verify Lockout/Tagout Check to Verify Lockout/Tagout Equipment is available.Equipment is available.
Is there a LO/TO plan, who is the Is there a LO/TO plan, who is the authorized person(s)?authorized person(s)?
Reference NFPA 70E 120 Establishing an Reference NFPA 70E 120 Establishing an Electrically Safe Work ConditionElectrically Safe Work Condition
Controlling Permanent Controlling Permanent PowerPower
MSG
EQ
DP2DP1
PPLP HVAC
Energized WorkEnergized Work
Energized WorkEnergized WorkFrom NFPA 70E 130From NFPA 70E 130
Safety Requirements are the same wither Safety Requirements are the same wither the employee is working on or near the employee is working on or near energized parts energized parts
Voltage Testing, Trouble Shooting, Voltage Testing, Trouble Shooting, working in a panel with the main in the working in a panel with the main in the off position but the lugs are energized.off position but the lugs are energized.
Energized WorkEnergized Work
You must have justification to work on You must have justification to work on energized circuits or partsenergized circuits or parts In short, if you are going to put other In short, if you are going to put other
people’s lives in danger by turning off the people’s lives in danger by turning off the power – you have justification.power – you have justification.
A work permit and Job briefing/planning A work permit and Job briefing/planning checklist must be completed before working checklist must be completed before working energized energized
Energized WorkEnergized Work
If there is any chance circuits or parts If there is any chance circuits or parts may be energized, they are to be treated may be energized, they are to be treated as energized until verified as de-as energized until verified as de-energized, meaning PPE required.energized, meaning PPE required.
Energized WorkEnergized Work
Use barricades to prevent or limit access Use barricades to prevent or limit access to work areas with un-insulated energized to work areas with un-insulated energized conductors or circuit parts conductors or circuit parts
Or an attendant shall be stationed to Or an attendant shall be stationed to warn and protect employeeswarn and protect employees
Topics DiscussedTopics Discussed
Electricity's Beginning OnsiteElectricity's Beginning Onsite
Temporary Power/LightingTemporary Power/Lighting
GFCI vs. Circuit BreakerGFCI vs. Circuit Breaker
Power ToolsPower Tools
Safe Guarding Permanent PowerSafe Guarding Permanent Power
Energized WorkEnergized Work
QUESTIONS?QUESTIONS?