Electrical Hazards for Fire and Electrical Hazards for Fire and Rescue DepartmentsRescue Departments

Part III: Fires Near High Tension Power LinesPart III: Fires Near High Tension Power Lines

Captain I Gary C. DizeCaptain I Gary C. DizeHealth and Safety DivisionHealth and Safety Division

Fairfax County, VirginiaFairfax County, Virginia

High tension lines are typically High tension lines are typically located in right-of-ways. located in right-of-ways.

They can be along railroad track They can be along railroad track beds, un-buildable tracks of land, or beds, un-buildable tracks of land, or commercial property yards. commercial property yards.

They can pose a number of They can pose a number of problems, such as access, uneven problems, such as access, uneven terrain, lack of water supply, and terrain, lack of water supply, and poor visibility due to lighting poor visibility due to lighting conditions.conditions.

Electrical HazardsElectrical HazardsFires Near High Tension Towers:Fires Near High Tension Towers:

Fires Near High Tension Towers:Fires Near High Tension Towers:

OSHA requires greater than 10 feet of OSHA requires greater than 10 feet of clearance from lines that are over clearance from lines that are over 50,000 volts. For example, the 50,000 volts. For example, the minimum clearance for a 500,000-volt minimum clearance for a 500,000-volt line is 18 feet. There are no visible line is 18 feet. There are no visible markers to identify a power line’s markers to identify a power line’s voltage, so call the local electric utility voltage, so call the local electric utility for clearance information if you are for clearance information if you are unsure. unsure.

Transmission lines mounted on steel Transmission lines mounted on steel towers normally are 110,000 – towers normally are 110,000 – 500,000 volts. 500,000 volts.

Electrical HazardsElectrical Hazards

Fires Near High Tension Towers:Fires Near High Tension Towers:

Transmission lines have sensitive Transmission lines have sensitive breakers, but WILL NOT prevent breakers, but WILL NOT prevent death or injury from contact.death or injury from contact.

Transmission lines require greater Transmission lines require greater safe working distances than the safe working distances than the normal due to higher voltage normal due to higher voltage (example: 500,000 volts = 18 feet).(example: 500,000 volts = 18 feet).

Electrical HazardsElectrical Hazards

Fires Near High Tension Towers:Fires Near High Tension Towers:

Transmission lines Transmission lines 500,000 volts and under 500,000 volts and under will sometimes have an will sometimes have an electric field near them. electric field near them. The field may cause a The field may cause a static shock to firefighters static shock to firefighters and large equipment and large equipment located in the field.located in the field.

Fires such as: brush, Fires such as: brush, trees, buildings, and auto trees, buildings, and auto fires have the potential to fires have the potential to weaken the lines and weaken the lines and insulators, causing failure insulators, causing failure of the towers.of the towers.

Electrical HazardsElectrical Hazards

Fires Near High Tension Towers:Fires Near High Tension Towers:

No matter how routine the fire No matter how routine the fire may appear, a plan of action is may appear, a plan of action is needed and all crew members needed and all crew members need to be advised.need to be advised.

The plan should include: what is The plan should include: what is burning, the terrain, life hazards burning, the terrain, life hazards and whether we should we let it and whether we should we let it burn or put it out.burn or put it out.

Solids streams should never be Solids streams should never be used; it provides a conductive used; it provides a conductive path for electricity.path for electricity.

Electrical HazardsElectrical Hazards

Case Study: Part III Case Study: Part III Close Call involving High Tension LinesClose Call involving High Tension Lines

(Please see PDF Handout)(Please see PDF Handout)

Electrical HazardsElectrical Hazards

DiscussionDiscussion Vehicle positioning on all incidents is critical to the safe operation and crew Vehicle positioning on all incidents is critical to the safe operation and crew

safety. Sometimes vehicle positioning cannot be placed completely out of safety. Sometimes vehicle positioning cannot be placed completely out of the way of danger; however, it is paramount that the crew is aware of the the way of danger; however, it is paramount that the crew is aware of the hazards once the vehicle has been positioned.hazards once the vehicle has been positioned.

All FRD personnel are reminded to increase safety awareness and to All FRD personnel are reminded to increase safety awareness and to provide a risk analysis when responding to any fire. The decision-making provide a risk analysis when responding to any fire. The decision-making process must start prior to the arrival and a plan to mitigate the incident process must start prior to the arrival and a plan to mitigate the incident should be discussed. This includes the level of PPE for the identified should be discussed. This includes the level of PPE for the identified hazard.hazard.

DiscussionDiscussion All FRD personnel need to maintain situational awareness on all All FRD personnel need to maintain situational awareness on all

incidents no matter the nature. Also, all members of a crew need incidents no matter the nature. Also, all members of a crew need to have the same incident action plan and follow the plan to to have the same incident action plan and follow the plan to mitigate the situation. Other tools that should have been used mitigate the situation. Other tools that should have been used would be the Crew Resource Management model and the would be the Crew Resource Management model and the Firefighter Life Safety Initiatives, which empowers all personnel Firefighter Life Safety Initiatives, which empowers all personnel to identify any and all hazards and alerts other crew members to to identify any and all hazards and alerts other crew members to the hazard.the hazard.

All FRD personnel are to be reminded that, per the power All FRD personnel are to be reminded that, per the power company, when any equipment comes in contact with an company, when any equipment comes in contact with an overhead power line, personnel are to stay put and keep others overhead power line, personnel are to stay put and keep others away from the equipment in question until the power company away from the equipment in question until the power company personnel gives the personnel gives the “all clear.” “all clear.” If imminent danger forces you off If imminent danger forces you off of the equipment, jump clear, keeping both feet together without of the equipment, jump clear, keeping both feet together without touching the equipment and ground at the same time.touching the equipment and ground at the same time.