TFD Electrical Hazards Policy

Overview

• The document outlines the TFD's policy to minimize electrical hazards for firefighters
• Procedures include disconnecting electrical service, downed wires response, choosing extinguishing agents, and dismounting from vehicles contacting energized conductors
• The policy applies to all uniformed personnel

Policy Updates and References

• This document replaces TFD Policy 5028, which concerns Electrical Hazards and was dated 11/2001
• There are no associated forms
• Reference TFD Policy 5016 for PPE, TFD Policy 5021 for ground ladder safety, and the TFD Pamphlet on electrical safety for firefighters for TFD-related information

Responsibilities Overview

• The Assistant Chief of Administration maintains the document
• Incident Commanders identify hazards, ensure precautions, and request utility assistance
• All TFD personnel need to be aware of and abide by the guidelines

Definitions

• Aerial Equipment: Aerial ladders, towers, or platforms, including telesquirt booms mounted on TFD apparatus
• Conductor: A substance that carries electrical current
• Danger Zone: Area around an electrical hazard where access is denied for safety
• Drip Loop: Loop of service wires at the mast to prevent water entry
• GFCI: Ground fault connection interrupter
• Kilovolt (kV): Unit of voltage equal to 1000 volts; 50 kV = 50,000 volts
• Low Voltage Line: Electrical line rated at 750 volts or less
• Mast: Vertical pipe that serves as a conduit for electrical service wires
• One-Span Rule: The span length between two poles/towers, which is the minimum clearance to maintain from downed wires or damaged poles

References

• WAC 296-305-04509: Aerial ladders
• WAC 296-305-06007: Electrical
• WAC 296-305-05001: Emergency fireground operations – Structural

General Guidelines

• Direct efforts to protect people/property and maintain distance until utility company arrives
• Cooperate with utility personnel to ensure safety
• All members receive training to identify electrical hazards
• Only utility company personnel should cut drip loops, open transformers or pull power meters

Operational Guidelines for Incident Commanders

• When operating near energized equipment, Incident Commanders need to identify electrical hazards as part of scene size-up
• Ensure that personnel don full protective clothing, including eye protection
• Take precautions to prevent electrical injuries
• Keep the public away from hazard areas
• Request utility company response for operations near electrical lines/equipment

Guidelines for Personnel

• Don full protective gear and follow procedures to prevent injury
• Shut off power per guidelines
• Survey for overhead wires prior to raising ground ladders
• Place ground ladders away from overhead electrical wires
• Maintain safe distances between aerial equipment and energized lines based on voltage

Distance Requirements

• Maintain at least ten feet from lines rated up to 50 kV
• Maintain at least ten feet plus 0.4 inches/1 kV from lines above 50 kV
• In the field, maintain ten feet plus one foot/insulator skirt for lines above 50 kV and aerial equipment
• Maintain the line distance between firefighters using aerial equipment and tools
• Keep aerial equipment away from low voltage lines to prevent contact

Prohibited Actions

• Avoid positioning apparatus under overhead wires
• Do not cut electrical wires, open transformers, or pull power meters
• Do not operate switches/controls on poles, manholes, vaults, transformers, or substations
• Do not enter flooded basements or rooms to access electrical service panels

Safety Guidelines

• Wear full protective clothing on scenes with electrical hazards per TFD Policy 5016
• Understand the limitations of turnout gear
• Keep a hand out with palm facing the body in low visibility areas
• Be alert for electrical hazards on the interior or exterior of a structure
• Find overhead and underground conductors when working near a structure
• Be observant when raising and lowering ground ladders
• Be aware of wire locations during roof operations
• Avoid wires when hoisting, lowering items, or removing debris
• Switch off breakers at the electrical panel per guidelines
• Dismount apparatus contacting energized conductors per guidelines

Use of Electrical Equipment

• In-line GFCI protection is required for watervacs and temporary lighting in moist/hazardous conditions
• Use sump pumps in de-energized areas only lowering them with ropes
• Place portable generators on the ground before use
• Use only extension cords rated at a minimum of 20 amps

Disconnecting Electrical Service Procedure

• Disconnect power at the service panel only if the firefighter, the panel, and the floor are dry
• Switch off the main breaker or remove fuses.
• Note the original position of breakers for Fire Investigators
• Remember that other panels may be present

Emergency Power Considerations

• Recognize that structures may have backup generators that may engage automatically
• Have the utility company disconnect electrical service at the pole if power cannot be shut off, or work needs to be done near the mast, drip loop, or service panel

Prohibited actions

• Cutting any wires, including drip loops is not allowed
• Pulling electrical meters is also prohibited
• Entering flooded basements to shut off the power

Responding to Downed Wires

• Establish a Danger Zone using the one-span rule, increasing it, if the ground is wet or conductors are present
• Stay in your vehicle
• Use hazard tape or rope to mark boundaries, enlarging the danger zone if there is a guardrail or metal fence
• Use enough personnel, law enforcement or company personnel so others dont enter The Danger Zone

Safety First

• Do not touch, roll up, or move wires
• Assume all electrical wires are energized and treat downed or sagging wires as live
• Previously "dead" wires may become re-energized
• Do not assume that telephone, cable TV, or guy wires are harmless
• The ground itself may become energized. The ground voltage varies

Sensations

• If you notice a tingling sensation in your feet, take this as a warning to immediately leave the area
• Downed wires may cause brush fires, so look for wires before entering the area
• If rescue or patient extrication is necessary, have the utility company shut off the power before entering the Danger Zone

Extinguishing Agents: Advice

• Avoid using water streams and consider Class C extinguishers as alternatives
• The metal extinguisher cylinder/discharge horn may be conductive when wet/dirty
• If using water, maintain 20 feet & use fog streams only
• Use carbon dioxide flooding if a vault can be sealed

Dismounting Protocol

• If a vehicle contacts an energized conductor, the apparatus may become energized and death/injury may occur if someone touches the apparatus or ground
• Dismount by jumping with both feet together, do not use handrails or grab bars, and do not maintain contact with both the apparatus and the ground simultaneously

Fires Near Utility Poles or Towers

• For brush or grass fires, extinguish with conventional means and notify TPU, as metal towers can be structurally weakened if exposed to fire
• Position apparatus clear of wires for fires near the top of poles
• Keep people away from poles and the wires
• Leave fires alone and await TPU if no further damage is expected
• If the pole is weakening consider directing a fog stream over the top allowing droplets to rain on the fire

Electrical Substation and Vault emergencies

• Protect people and property
• Maintain traffic control and await power company personnel
• Do not enter or fight a fire until authorized/assisted by the power company
• Do not operate electrical switches/controls as designs may not accommodate flowing current and improper operation may cause arcing, damage, or explosions

Firefighter safety risks

• Fire and explosion hazards from transformer oil
• Equipment that can’t be de-energized
• Energized soil or water
• Arcing/exploding insulators
• Toxic gases from burning insulation and oil
• Explosions when manhole covers are disturbed/removed
• All TFD confined space policies apply to underground electrical vaults.

Policy requirements

• For electrical fires in substations or vaults it is required that TFD must wait for the electrical equipment to be de-energized, and authorization from TPU