Mon Power_Safety and the First Responder_Rev May 2012

7/31/2019 Mon Power_Safety and the First Responder_Rev May 2012

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and the

Responder For Emergency Medical Services, Public

Safety and Public Works Employees



Safety and the First Responder 2

Did You Know … ?

s

Electricity travels 186,000 miles per second – If you had a lamp on the moon connected to a switch in your

house, it would take just over one second for it to light up

s One lightning strike can generate 100 million to 1 billion

volts of electricity

s A typical lightning bolt is hotter than the surface of the sun






Arch Flash

s

Typical building fire – Temperatures can reach 1,100 to 1,800 degrees Fahrenheit over

several minutes

s Primary arch flash reaches

11,000 degrees Fahrenheit

in one-tenth of a second




Electrical Shock

s Electrical shocks occur when a part of your body

completes an electrical circuit by …

– Touching a live wire and an electrical ground, or

– Touching a live wire and another wire at a different voltage

An electrical shock is received when electrical current

passes through the body




Volts vs. Amps

s

Voltage measures the pressure driving the electric current – Humans can withstand thousands of volts

– Stun guns = 50,000 volts, but no amps

s Amperage, or amps, measures the amount of current

– Presents the greatest danger during electrical contact – One-fifth of 1 amp – about what a household night light carries –

can stop the human heart

s More people are killed from 120/240 volts

than any other voltage


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Electric Shock

Amps, or current (not voltage), causes electric shock

Milliamps(mA)

Affect on Person

0.5 – 3 Tingling sensations

3 – 10 Muscle contractions and pain

10 – 40 “Let-go” threshold

30 – 75 Respiratory paralysis

100 – 200 Ventricular fibrillation

200 – 500 Heart clamps tight

1500 + Tissue and organs start to burn

Note: Reaction will vary with frequency and time of exposure



Shock Severity

s

Severity of the shock depends on: – Path of electric current through the body

– Amount of current flowing through the body (amps)

– Duration of the current through the body

s Remember, low voltage does not mean low hazard



The Danger of Electric Shock

s

Over 30,000 non-fatal electrical shock accidents occur eachyear in the U.S.

– Over 600 people die from electrocution each year

s Electrocution remains the fourth-highest cause of industrial

fatalities

s Most injuries and deaths could be avoided



Things May Not Be As They Appear

s

Don’t assume that when a wire isn’t sparking it isn’tenergized

– A downed power line may still be energized

s Don’t assume that a phone or coaxial cable line isn’t

energized

– It’s possible that a few spans away, an energized power line could

be touching the phone or cable line, energizing it as well

– And there’s always the possibility that what you think is a phone

line is really a power line

– Both cable TV and phone lines can carry 7,200 volts!

s There could be hazards that you can’t see

– A downed line that is hidden by vegetation; an energized, downed

line a few spans away; and other hazards could still be present



Single Primary Conductor

Fiber Optics

SecondariesStreet Light

Electric Service wire

Cable wire

Telephone wire

System Neutral



Electrical Hazards

s Voltage decreases as the distance from the point of contact

increases

Step Potential




Electrical Hazards

s Always treat all downed wires, including cable TV and

telephone wires, as energized at high voltage until proven

otherwise

Types of Emergencies: Downed Wires




Electrical Hazards

Types of Emergencies: Downed Wires




Pole Identification

s Every pole is identified by a number

s Number is located on the side of the pole that faces the

street, approximately 6 feet above the ground

s If the number is missing, check a nearby pole and use it as a

reference point




Reporting Emergency Locations

s Describe nature of the emergency and whether personal

injury or danger is involved

s Identify community, town or borough

– Building number

– Street names Nearest cross street and direction (north, east, west or

south) from the location

s Identify equipment numbers (pole, pad-mount)

s Note whether emergency is on the street side or rear of

property

s Provide call-back number




Describe the Damage

s Primary: low, down, sparking

s Transformer: down, leaking, sparking

s Secondary: low, down, sparking

s Pole: broken, leaning, down, on fire

s House service: low, down, sparking

If you identify cable TV or

telecommunications equipment that is in

contact with electrical equipment, call the

local utility immediately




How Electricity is Delivered to You

Power Plant

High-Voltage

Transmission Lines

Power Substation

Transformer

Transformer Drum

Power Poles




Transmission Towers




Distribution System Overview

s Distribution Primary Voltage

– 19.9 kV

– 12.5 kV

– 4,800 kV

– 4160 kV




Underground Pad-Mount Transformers

s Stay at least 30 feet away from a pad-mount transformer if it

appears to be damaged, or if it’s making unusual noise

– These are the green metal boxes that contain the above ground

portion of an underground electrical installation

– They transform high-voltage electricity to low-voltage electricity

which is then carried in insulated underground power lines to

homes and businesses

s If you see a pad-mount transformer that looks

damaged, or appears to have been tamperedwith, please notify Mon Power

Pad-mount transformers may be energized!




Electrical Fires and Arcing at Substations

Stay away from electrical substations!

s Electrical fires and arcing that may occur at an electrical

substation are highly dangerous

s Do not go near, or enter a substation, under any

circumstances unless accompanied by a utility companyrepresentative




Electrical Hazards

Downed Wires

Types of Emergencies




Electrical Hazards – Types of EmergenciesDowned Wires

Upon arrival

s Establish a safety zone and secure the area

s If possible, the safety zone should extend a minimum of two

full span lengths of wire in each direction beyond the

downed wire

– Poles may break and fall due to stress

– Wires can slip through insulators and sag to the ground

– Wires may be contacting metal fences, guard rails, buildings, etc.




Electrical Hazards – Types of EmergenciesDowned Wires

s Bodies in contact with live wires may be energized.DO NOT TOUCH the individual until the wire is tested and

cleared from the body

s Wires should not be assumed dead until they are tested

dead or certain assurance from local utility personnel isreceived




Electrical Hazards

Vehicle/Pole Accidents





Electrical Hazards – Types of EmergenciesVehicle / Pole Accidents

s All potential hazards should be thoroughly evaluated

s Approach cautiously – establish a safety zone

s If fire is present, use a fog pattern rather than a straight

stream

s Remember: the vehicle and anything attached to it may be

energized

s Do not come within 30 feet of the vehicle





s Occupants have one overriding thought … to get out of thevehicle

s Gain their confidence and then order them to remain in the

vehicle





s If it is absolutely necessary to have the occupants exit thevehicle, they should be given explicit instructions and told

not to come in contact with the vehicle and the ground at the

same time

s

Once on the ground, small shuffling steps should be takento move away from the involved vehicle (remember - step

potential)




Electrical Hazards

Ladders and Other Lifts





Ladders and Other Lifts

s Before raising or extending any kind of ladder, metal pole, or

other equipment capable of reaching a power line, check in

all directions for power lines

s Be careful while carrying or positioning any kind of ladder,

tool, equipment, or extension and keep them well away from

energized overhead power lines, especially the weather heador service drop




Electrical Hazards

Summary





Electrical Hazards – Types of EmergenciesSummary

s Treat all wires as dangerous and energized at high voltageuntil tested and proven otherwise

s Exercise extreme caution when approaching the scene,

especially at night

s Establish a safety zone and prevent all unauthorized persons

from approaching the scene

s Secure the scene until relieved by local utility

s

Never tamper with energized wires or equipment




Electrical Safety: Fact or Fiction?

Power lines are insulated so people are protectedfrom contact.

FICTION: Power lines may have acover to protect against weather, but

they are not insulated for contact.

(Birds can perch on power lines unhurt

because they don’t have a path to the

ground – you and your ladder do.)





I should keep myself and any equipment I’m using at

least 30 feet away from power lines.

FACT: Electricity can jump, or arc,from a power line to a person who

gets too close.

To be safe, keep yourself, others, and

any equipment at least 30 feet frompower lines.





A person can be electrocuted by a power line even

when wearing work gloves and rubber boots.

FACT: Work gloves and rubber bootsoffer no protection against contact with

power lines. Only properly trained

workers with personal protective

equipment are allowed to work near

power lines.





Downed power lines don’t carry any electricity.

FICTION: Assume all downed wires are

energized and potentially dangerous.Be sure to stay 30 feet away from power

lines.

Call Mon Power at 1-888-544-4877

immediately to report a downed power line.





It’s unsafe to drive your car near fallen power lines.

FACT: Avoid streets with fallen power lines and take an alternate route. Do not,

under any circumstances, drive over

downed electrical wires.

If your car comes in contact with adowned line, stay in your vehicle, call

911 immediately and wait for help.





If children lose a baseball, model airplane or kiteinside a substation, they never should enter the

substation to retrieve it.

FACT: Substations are places where electricityis stepped down from high voltages used to

move it over long distances to lower voltages

used inside the home.

Educating children on the dangers of electrical

substations is the first line of defense for keeping them out of harms way!



and the First Responder Emergency Medical Services, Public Safety and Public Works Employees

Documents

Mon Power_Safety and the First Responder_Rev May 2012