Controlling the utilities

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““ Excellence Through TrainingExcellence Through Training
””

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Firefighter SafetyFirefighter Safety
Controlling the UtilitiesControlling the Utilities
Natural GasNatural Gas ElectricityElectricity
DANGER

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Properties of Natural GasProperties of Natural Gas
1971
1 0

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Odorless – Colorless - TastelessOdorless – Colorless - Tasteless
Methyl Mercaptan is added to give it it’sMethyl Mercaptan is added to give it it’s
distinguishable “rotten egg” odordistinguishable “rotten egg” odor
Odorized natural gas is detectable atOdorized natural gas is detectable at
concentrations significantly less than 1%concentrations significantly less than 1%

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Non-ToxicNon-Toxic
94% - methane94% - methane 4% - ethane4% - ethane
Often listed as a “Hazardous Material” due to it’sOften listed as a “Hazardous Material” due to it’s
flammability, not it’s toxicityflammability, not it’s toxicity
Only through it’s ability to displace oxygen can itOnly through it’s ability to displace oxygen can it
pose an asphyxiation hazardpose an asphyxiation hazard

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Vapor DensityVapor Density
30% lighter than air30% lighter than air
Will rise and collect near the ceiling
Natural Gas
0.7
Air = 1
Propane
1. 56

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Flammable LimitsFlammable Limits
4.5%
Too Lean
14%
Too Rich

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Heating ValueHeating Value
1,000 BTU per cubic foot1,000 BTU per cubic foot

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Combustion ProductsCombustion Products
Complete combustion = heat, carbon dioxide & waterComplete combustion = heat, carbon dioxide & water
vaporvapor
Incomplete combustion = carbon monoxideIncomplete combustion = carbon monoxide

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Ignition TemperatureIgnition Temperature
Natural Gas - 1163Natural Gas - 1163º Fº F
Propane - 957Propane - 957º Fº F
Gasoline - 632Gasoline - 632º Fº F

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Natural Gas SupplyNatural Gas Supply

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Approx. Range
of Flammability
(% mix with air)
Vapor Density
(Air = 1.0)
Approximate
Ignition
Temperature
Natural Gas 4.5 - 14.0 .70 1163ºF
Hydrogen 4.0 – 7.5 .07 1076ºF
Propane 2.2 – 9.5 1.56 957ºF
Butane 1.9 – 8.5 2.01 912ºF
Gasoline 1.4 – 7.6 3.00 632ºF
ComparisonsComparisons

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Natural Gas EquipmentNatural Gas Equipment
Distribution SystemDistribution System
Type of System Pressure
Transmission Line
(High Pressure)
300 – 1000 psig
Distribution Main
(High Pressure)
60 – 300 psig
Distribution Main
(Modified High Pressure)
5 – 60 psig
Distribution Main
(Low Pressure)
¼ psig
Service / Customer
Line
¼ psig

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Each time the pressure is reduced, overEach time the pressure is reduced, over
pressure protection is provided by a reliefpressure protection is provided by a relief
valve or automatic shut offvalve or automatic shut off
A relief valve venting gas to the atmosphere isA relief valve venting gas to the atmosphere is
performing its proper function and should never be cutperforming its proper function and should never be cut
off or restricted until the gas company arrives and makesoff or restricted until the gas company arrives and makes
corrections to the systemcorrections to the system

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Material Color Size Pressure
Bare Steel - - - - - - 2” – 6” Up to 60 psi
Wrapped
Steel
Yellow /
brown ½” – 20”
Up to 1000
psi
Wrought
Iron
- - - - - - 2” – 6” Up to 60 psi
Polyethylene
Plastic
Black /
orange /
yellow
½” – 6” Up to 60 psi
Cast Iron - - - - - - 4” – 20” ¼ psi
Copper - - - - - - ¼” - ½” ¼ psi
PipingPiping

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POLYETHYLENE PIPE
Polyethylene pipe is buried with a 12 gaugePolyethylene pipe is buried with a 12 gauge
wire for ease of locating – it has nothing to dowire for ease of locating – it has nothing to do
with grounding or bondingwith grounding or bonding
PipingPiping

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Distribution piping is normally buriedDistribution piping is normally buried
between 12” and 18” below ground levelbetween 12” and 18” below ground level
PipingPiping

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Shut-off ValvesShut-off Valves
Square - HandleSquare - Handle
L - HandleL - Handle
T - HandleT - Handle
Side ViewSide View

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Shut-off ValvesShut-off Valves
Closed PositionClosed Position
Open PositionOpen Position
Top ViewTop View

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Typical Residential InstallationTypical Residential Installation

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Regulator
Relief Valve
Valve

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Meter

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Commercial InstallationCommercial Installation
Meter
Valve
Regulator

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Natural Gas EmergenciesNatural Gas Emergencies
Types of EmergenciesTypes of Emergencies
Odors / LeaksOdors / Leaks
FireFire

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Emergency ResponseEmergency Response
Odors / LeaksOdors / LeaksInsideInside
1)1) Approach incident from upwind, if possible.Approach incident from upwind, if possible.
2)2) Position apparatusPosition apparatus at leastat least 150” from scene.150” from scene.
3)3) Investigate for the source of the odor with the GasTracInvestigate for the source of the odor with the GasTrac
& Mini-Gas.& Mini-Gas.
WCB prohibits entry into a confined space having an atmosphereWCB prohibits entry into a confined space having an atmosphere
containing over 10% LEL combustible gascontaining over 10% LEL combustible gas
4)4) If a strong odor is encountered or leak is confirmed,If a strong odor is encountered or leak is confirmed,
evacuate the bldg. of all occupants.evacuate the bldg. of all occupants.

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Odors / LeaksOdors / LeaksInsideInside
5)5) Notify BC GAS - Gas Op's to respond.Notify BC GAS - Gas Op's to respond.
6)6) Ventilate the bldg. by opening doors & windows.Ventilate the bldg. by opening doors & windows.
Remember to open windows on top.Remember to open windows on top.
7)7) Do not operate electrical switches / telephones.Do not operate electrical switches / telephones.

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9)9) If a leak is confirmed, the IC should determine if it canIf a leak is confirmed, the IC should determine if it can
be stopped or if the gas needs to be shut off at the valve.be stopped or if the gas needs to be shut off at the valve.
OKOK
InsideInside
8)8) Use only intrinsically safe radios / handlights.Use only intrinsically safe radios / handlights.

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11)11) Gas valves turned OFF by FD personnel SHOULDGas valves turned OFF by FD personnel SHOULD
NEVER be turned back on without BC GAS - Gas Op'sNEVER be turned back on without BC GAS - Gas Op's
on scene.on scene.
12) No one should re enter the bldg. until BC GAS - Gas12) No one should re enter the bldg. until BC GAS - Gas
Op's has secured the leak and determined that it is safeOp's has secured the leak and determined that it is safe
to enter.to enter.
InsideInside
10) Hand tools should be spark-proof10) Hand tools should be spark-proof
(1663 / 1665).(1663 / 1665).

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Odors / LeaksOdors / LeaksOutsideOutside
1)1) If unignited gas is escaping from the ground, eitherIf unignited gas is escaping from the ground, either
from an excavation site or from an open pipe outside offrom an excavation site or from an open pipe outside of
a bldg., notify BC GAS - Gas Op's immediately.a bldg., notify BC GAS - Gas Op's immediately.
2)2) Establish a safe area around the incident scene.Establish a safe area around the incident scene.
3)3) Extinguish all open flames.Extinguish all open flames.
4)4) Check surrounding bldgs., especially basements, for theCheck surrounding bldgs., especially basements, for the
presence of gas.presence of gas.
Gas can migrate through the ground, following pipes or naturalGas can migrate through the ground, following pipes or natural
stratifications in the earth.stratifications in the earth.

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5)5) Restrict or re-route traffic until BC GAS - Gas Op'sRestrict or re-route traffic until BC GAS - Gas Op's
personnel can bring the gas flow under control.personnel can bring the gas flow under control.
6)6) Although water fog streams can be used to disperseAlthough water fog streams can be used to disperse
escaping vapors, they are usually ineffective since theescaping vapors, they are usually ineffective since the
lighter-than-air gas naturally rises.lighter-than-air gas naturally rises.
7)7) If water fog is used, caution must be exercised to avoidIf water fog is used, caution must be exercised to avoid
filling excavation sites with water.filling excavation sites with water.

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8)8) FD personnel should never clamp or crimp a gas line.FD personnel should never clamp or crimp a gas line.
Static electricity could ignite escaping gas, resulting in aStatic electricity could ignite escaping gas, resulting in a
sudden and violent ignition.sudden and violent ignition.
9)9) Hand tools should be spark-proofHand tools should be spark-proof
(1663 / 1665).(1663 / 1665).

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FiresFires
InsideInside
1)1) Notify BC GAS - Gas Op's immediately upon receipt ofNotify BC GAS - Gas Op's immediately upon receipt of
alarm.alarm.
2)2) The IC should determine if the gas can safely be shut offThe IC should determine if the gas can safely be shut off
inside the bldg. or at the meter.inside the bldg. or at the meter.

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FiresFires
InsideInside
3) In certain industrial / commercial settings, turning off the3) In certain industrial / commercial settings, turning off the
gas supply can seriously interrupt important and costlygas supply can seriously interrupt important and costly
industrial processes and should only be done uponindustrial processes and should only be done upon
evaluation with company personnel and BC GAS - Gasevaluation with company personnel and BC GAS - Gas
Op's.Op's.
4) If the gas supply cannot be shut off, the surrounding4) If the gas supply cannot be shut off, the surrounding
combustibles should be kept wet with a fog stream.combustibles should be kept wet with a fog stream.

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FiresFiresOutsideOutside
1)1) Notify BC GAS - Gas Op's immediately upon receipt ofNotify BC GAS - Gas Op's immediately upon receipt of
alarm.alarm.
2)2) The best method of controlling outdoor gas fires is toThe best method of controlling outdoor gas fires is to
shut off the gas flow.shut off the gas flow.
3)3) In most cases, FD personnel should not attempt toIn most cases, FD personnel should not attempt to
extinguish the fire while the gas is still escaping.extinguish the fire while the gas is still escaping.
4)4) BURNING GAS WILL NOT EXPLODE.BURNING GAS WILL NOT EXPLODE.

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FiresFiresOutsideOutside
5) Secure the area and protect exposures, if necessary.5) Secure the area and protect exposures, if necessary.
6)6) IF it is necessary to extinguish the fire before the gasIF it is necessary to extinguish the fire before the gas
flow can be stopped, use a Dry Chem extinguisherflow can be stopped, use a Dry Chem extinguisher
aimed at the base of the flame and wet the surroundingaimed at the base of the flame and wet the surrounding
area with water fog to prevent the re-ignition ofarea with water fog to prevent the re-ignition of
combustibles.combustibles.

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Electrical EmergenciesElectrical Emergencies

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Electrical HazardsElectrical Hazards
TransformerTransformer
Primary LinesPrimary Lines
Secondary LinesSecondary Lines
Cable TV /Cable TV /
Telephone LinesTelephone Lines InsulatorsInsulators

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Primary LinesPrimary Lines
- located at the highest level of the polelocated at the highest level of the pole
- carry the greatest amount of powercarry the greatest amount of power
- normally bare wire, which gives themnormally bare wire, which gives them
the “look” of support cablesthe “look” of support cables

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Secondary LinesSecondary Lines
- located one level below the primarylocated one level below the primary
lines, at the second-highest level of thelines, at the second-highest level of the
pole.pole.
- carry voltages less than primaries.carry voltages less than primaries.
- may be coated for protection from themay be coated for protection from the
elements. This coating DOES NOTelements. This coating DOES NOT
provide insulation from live current.provide insulation from live current.

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Cable TV / Telephone LinesCable TV / Telephone Lines
- located at the lowest level of the polelocated at the lowest level of the pole
- carry lower voltages than primaries & secondariescarry lower voltages than primaries & secondaries
- should be coated for protection from the elements. Thisshould be coated for protection from the elements. This
coating DOES NOT guaranty insulation from live current.coating DOES NOT guaranty insulation from live current.
- should always be considered dangerous due to back-should always be considered dangerous due to back-
feeding or cross-conduction.feeding or cross-conduction.

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Downed WiresDowned Wires
Pole / Transformer FiresPole / Transformer Fires
Vehicle / Pole AccidentsVehicle / Pole Accidents
Wires on VehicleWires on Vehicle
Vehicles Contacting WiresVehicles Contacting Wires
Manhole FiresManhole Fires
SubstationsSubstations
CAUTION CAUTION CAUTION CAUTION

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Step PotentialStep Potential
The voltage decreases as the distanceThe voltage decreases as the distance
from the point of contact increasesfrom the point of contact increases

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Always treat all downed wires, including Cable TV &Always treat all downed wires, including Cable TV &
telephone wires, as energized at high voltage until proventelephone wires, as energized at high voltage until proven
otherwise.otherwise.

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• It is impossible to determine if a wire is energized by itsIt is impossible to determine if a wire is energized by its
appearance.appearance.
• Never attempt to move or cut any downed conductors.Never attempt to move or cut any downed conductors.
Remember, wooden or fiberglass pike poles MAY BERemember, wooden or fiberglass pike poles MAY BE
conductive.conductive.

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Upon arrivalUpon arrival
• Establish a safety zone and secure the area.Establish a safety zone and secure the area.
• If possible, the safety zone should extend a minimum ofIf possible, the safety zone should extend a minimum of
two full span lengths of wire in each direction beyond thetwo full span lengths of wire in each direction beyond the
downed wire.downed wire.
- poles may break and fall due to stresspoles may break and fall due to stress
- wires can slip through insulators and sag to the groundwires can slip through insulators and sag to the ground
- wire may be contacting metal fences, guard rails,wire may be contacting metal fences, guard rails,
buildings, etc.buildings, etc.

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Safety ZoneSafety Zone

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• Any high-voltage wire, when disturbed, can get outAny high-voltage wire, when disturbed, can get out
of control.of control.
• FF boots do not guaranty insulation from energizedFF boots do not guaranty insulation from energized
wires.wires.
• NO HIGH VOLTAGE wire is insulated. TheNO HIGH VOLTAGE wire is insulated. The
coating sometimes seen is to provide protection fromcoating sometimes seen is to provide protection from
the elements.the elements.

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• Bodies in contact with live wires may be energized.Bodies in contact with live wires may be energized.
DO NOT TOUCH the individual until the wire isDO NOT TOUCH the individual until the wire is
tested dead and cleared form the body.tested dead and cleared form the body.
• Wires should not be assumed dead until they areWires should not be assumed dead until they are
tested dead or certain assurance from BC HYDROtested dead or certain assurance from BC HYDRO
personnel is rec’d.personnel is rec’d.

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• If a downed wire is involved in the fire, use a fogIf a downed wire is involved in the fire, use a fog
pattern to keep the fire in check and protect thepattern to keep the fire in check and protect the
surrounding area.surrounding area.
• If the fire is at the top of the pole, or is on pole-mountedIf the fire is at the top of the pole, or is on pole-mounted
equipment, and it appears that the fire will not endangerequipment, and it appears that the fire will not endanger
life or property, let it burn. Remember, once electricallife or property, let it burn. Remember, once electrical
equipment is involved in fire, it is not salvageable.equipment is involved in fire, it is not salvageable.

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• In the rare case where the fire must be attacked and/orIn the rare case where the fire must be attacked and/or
the equipment has not been de-energized, exercisethe equipment has not been de-energized, exercise
extreme caution.extreme caution.
• Most pole fires are caused by:Most pole fires are caused by:
– lightninglightning
– insulator breakdown (broken or contaminated byinsulator breakdown (broken or contaminated by
salt spray or air pollution)salt spray or air pollution)
– equipment failureequipment failure

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• As most pole-mounted equipment contains oil, theAs most pole-mounted equipment contains oil, the
extinguishing agents of choice are dry chemical andextinguishing agents of choice are dry chemical and
water fog.water fog.
• If the equipment is still energized, little can be done toIf the equipment is still energized, little can be done to
extinguish the fire, as the oil will continue to re-ignite.extinguish the fire, as the oil will continue to re-ignite.
• When in doubt, secure the area, establish a safety zoneWhen in doubt, secure the area, establish a safety zone
and allow BC HYDRO to arrive and determine the safeand allow BC HYDRO to arrive and determine the safe
and proper course of action.and proper course of action.

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• All potential hazards should be thoroughly evaluated.All potential hazards should be thoroughly evaluated.
• Approach cautiously - Establish a safety zone.Approach cautiously - Establish a safety zone.
• If a fire is present, use a fog pattern rather than straightIf a fire is present, use a fog pattern rather than straight
stream.stream.
•Remember: the vehicleRemember: the vehicle and anything attached to itand anything attached to it may bemay be
energized.energized.
•Approach the vehicle to no closer than 10 feet.Approach the vehicle to no closer than 10 feet.

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•Occupants have one overriding thought . . . . To get out ofOccupants have one overriding thought . . . . To get out of
the vehicle.the vehicle.
• Gain their confidence and order them to remain in theGain their confidence and order them to remain in the
vehicle.vehicle.
• In dire emergencies and under ideal conditions, the driverIn dire emergencies and under ideal conditions, the driver
can try to move the vehicle from underneath the wires.can try to move the vehicle from underneath the wires.
• However, the wire may weld itself to the vehicle –However, the wire may weld itself to the vehicle –
preventing movement.preventing movement.

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• If it is absolutely necessary to have the occupants exit theIf it is absolutely necessary to have the occupants exit the
vehicle, they should be given explicit instructions and told notvehicle, they should be given explicit instructions and told not
to come in contact with the vehicle and the ground at the sameto come in contact with the vehicle and the ground at the same
time.time.
• Once on the ground, small shuffling steps should be taken toOnce on the ground, small shuffling steps should be taken to
move away from the involved vehicle (remember - stepmove away from the involved vehicle (remember - step
potential).potential).

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In some cases, poles struck by a vehicle will sever, leavingIn some cases, poles struck by a vehicle will sever, leaving
the top portion suspended in air by the wires.the top portion suspended in air by the wires.
In these cases, if energized wires are not contacting theIn these cases, if energized wires are not contacting the
vehicle, the occupants should be evacuated and a secure zonevehicle, the occupants should be evacuated and a secure zone
established.established.
The supported section may fail, causing energized wires toThe supported section may fail, causing energized wires to
fall to the ground.fall to the ground.

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Vehicles contacting wiresVehicles contacting wires

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Procedures for vehicles in contact with energized wires are theProcedures for vehicles in contact with energized wires are the
same as those for vehicle / pole accidents.same as those for vehicle / pole accidents.
The “step potential” affects the area around the involvedThe “step potential” affects the area around the involved
vehicle, as well.vehicle, as well.
Unless threatened by fire or some other danger, occupantsUnless threatened by fire or some other danger, occupants
should remain on the vehicle until the wires can be de-should remain on the vehicle until the wires can be de-
energized.energized.

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The entire vehicle may be energized, causing tires and fluids toThe entire vehicle may be energized, causing tires and fluids to
burn, lug nuts to weld & other components to fail, especiallyburn, lug nuts to weld & other components to fail, especially
pressurized cylinders (bumpers / hatch lifts).pressurized cylinders (bumpers / hatch lifts).
Fires should be extinguished with a fog pattern – NOT aFires should be extinguished with a fog pattern – NOT a
straight stream.straight stream.

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• Notify BC HYDRO and BC GAS immediately uponNotify BC HYDRO and BC GAS immediately upon
receipt of the alarm.receipt of the alarm.
• Secure the area. Establish a safety zone.Secure the area. Establish a safety zone.
• If the cover is in place, do not attempt to remove itIf the cover is in place, do not attempt to remove it
without first consulting with BC HYDRO and BC GASwithout first consulting with BC HYDRO and BC GAS
personnel.personnel.
– If flammable gases are present, removing the coverIf flammable gases are present, removing the cover
may provide sufficient air to cause an explosion.may provide sufficient air to cause an explosion.
– If a transformer has failed and the oil is above it’sIf a transformer has failed and the oil is above it’s
ignition temperature, removing the cover may cause aignition temperature, removing the cover may cause a

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• A spark resulting from removing the cover may causeA spark resulting from removing the cover may cause
an explosion of gases in the manhole.an explosion of gases in the manhole.
• If there are gases present in the ductwork runningIf there are gases present in the ductwork running
from manhole-to-manhole, subsequent explosions couldfrom manhole-to-manhole, subsequent explosions could
occur down the line.occur down the line.
• Explosions have been known to propel a manhole coverExplosions have been known to propel a manhole cover
(which weigh approx. 270 lbs.) a significant distance.(which weigh approx. 270 lbs.) a significant distance.

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• If the manhole cover is already off,If the manhole cover is already off, do not enter thedo not enter the
manholemanhole or take any further action until the situation hasor take any further action until the situation has
been evaluated by BC HYDRO and BC GAS personnel.been evaluated by BC HYDRO and BC GAS personnel.
• Manholes must always be treated as highly hazardousManholes must always be treated as highly hazardous
confined spaces.confined spaces.
• Except for rescue, FD personnel should never enter aExcept for rescue, FD personnel should never enter a
manhole.manhole.

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REMEMBERREMEMBER
Unless there isUnless there is
human life at stake,human life at stake,
there is no greatthere is no great
urgency to extinguishurgency to extinguish
a fire or enter thea fire or enter the
manhole. Maximummanhole. Maximum
damage to thedamage to the
equipment hasequipment has
already taken place.already taken place.

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SubstationsSubstations HazardsHazards
• High voltage (overhead & underground)High voltage (overhead & underground)
• Open high-voltage workOpen high-voltage work
• Oil-filled switch gear, transformers, etc.Oil-filled switch gear, transformers, etc.
• Toxic smoke & gases due to burning oil & insulatingToxic smoke & gases due to burning oil & insulating
materialsmaterials
• Intense heat of a fire can collapse steel frameworkIntense heat of a fire can collapse steel framework
• Explosion from oil-filled equipmentExplosion from oil-filled equipment
• Exploding glass & porcelain insulatorsExploding glass & porcelain insulators
• Falling wiresFalling wires

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• FD personnel should not enter substations, eitherFD personnel should not enter substations, either
private or BC HYDRO, unless accompanied by BCprivate or BC HYDRO, unless accompanied by BC
HYDRO.HYDRO.
• Any electrical apparatus, transformer or switch thatAny electrical apparatus, transformer or switch that
has been on fire cannot be salvaged.has been on fire cannot be salvaged.
• Efforts should be directed at protecting surroundingEfforts should be directed at protecting surrounding
property and awaiting arrival of BC HYDRO.property and awaiting arrival of BC HYDRO.

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• Some equipment, such as circuit switches and breakers,Some equipment, such as circuit switches and breakers,
have porcelain housings that are pressurized with SF-6have porcelain housings that are pressurized with SF-6
gas. If they are involved in fire and sprayed with water,gas. If they are involved in fire and sprayed with water,
the sudden temperature change may cause a violentthe sudden temperature change may cause a violent
failure.failure.
• Never operate electric utility high-voltage switches thatNever operate electric utility high-voltage switches that
are within a substation property, mounted on poles, orare within a substation property, mounted on poles, or
located within manholes or vaults. Many of these are notlocated within manholes or vaults. Many of these are not
designed to drop electric load.designed to drop electric load.

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Structure FiresStructure Fires

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It is usually best to leave the power on to structures asIt is usually best to leave the power on to structures as
long as you safely canlong as you safely can
When safe firefighting tactics require the power to be shutWhen safe firefighting tactics require the power to be shut
off, the following actions are appropriate:off, the following actions are appropriate:
 de-energize the fire-affected area by removing fuses or openingde-energize the fire-affected area by removing fuses or opening
circuit breakers.circuit breakers.
 open the main disconnects to de-energize the entire bldg.open the main disconnects to de-energize the entire bldg.
 if the bldg. is damaged to the extent that service is no longer req’dif the bldg. is damaged to the extent that service is no longer req’d
or puts personnel in jeopardy, the service to the bldg. should beor puts personnel in jeopardy, the service to the bldg. should be
disconnected by BC HYDROdisconnected by BC HYDRO

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MetersMeters
BC HYDRO says . . .BC HYDRO says . . .
NeverNever pull an electricpull an electric
meter to de-energize ameter to de-energize a
bldg.bldg.

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MetersMeters
Reasons for NOT removing metersReasons for NOT removing meters
1)1) Pulling the meter may not de-energize the electric service to thePulling the meter may not de-energize the electric service to the
bldg.bldg.
~ Services over 200 amps are metered by current transformers.Services over 200 amps are metered by current transformers.
Pulling the meterPulling the meter will notwill not shut off the electric supply.shut off the electric supply.
~ Some meter bases are equipped with automatic bypasses.Some meter bases are equipped with automatic bypasses.
When the meter is removed, the bypasses close and the bldg.When the meter is removed, the bypasses close and the bldg.
remains energized.remains energized.
~ People have developed many unique methods to bypass thePeople have developed many unique methods to bypass the
meter.meter.

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MetersMeters
Reasons for NOT removing metersReasons for NOT removing meters
2)2) If there is a presence of explosive gases in the bldg., the service wireIf there is a presence of explosive gases in the bldg., the service wire
piping can act like a chimney. A small amount of gas may bepiping can act like a chimney. A small amount of gas may be
present in the meter socket and pipe. When the meter is removed, apresent in the meter socket and pipe. When the meter is removed, a
small arc will occur and the gas may explode.small arc will occur and the gas may explode.
3)3) If the meter is exposed to the heat of the fire, it can build up internalIf the meter is exposed to the heat of the fire, it can build up internal
stresses and explode on contact.stresses and explode on contact.
4)4) After a meter is removed, the energized contacts in the meter socketAfter a meter is removed, the energized contacts in the meter socket
are left exposed, posing a shock hazard to anyone near the meterare left exposed, posing a shock hazard to anyone near the meter
base.base.

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SummarySummary
Treat all wires as dangerous and energized at high voltageTreat all wires as dangerous and energized at high voltage
until tested and proven otherwise.until tested and proven otherwise.
Exercise extreme caution when approaching the scene,Exercise extreme caution when approaching the scene,
especially at night.especially at night.
Establish a safety zone and prevent all unauthorizedEstablish a safety zone and prevent all unauthorized
persons from approaching the scene.persons from approaching the scene.
Secure the scene until relieved by BC HYDRO.Secure the scene until relieved by BC HYDRO.
Never tamper with energized wires or equipmentNever tamper with energized wires or equipment..

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SummarySummary
Your primary responsibility is to save lives . . .Your primary responsibility is to save lives . . .
including your own.including your own.

Controlling the utilities

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