Electrical Hazards Awareness Program (EHAP)
Electrical Hazard Recognition
Each employee shall be trained to recognize and be qualified to work within proximity to electrical hazards that are applicable to the employee's assignment.
All overhead and underground electrical conductors and all communication wires and cables shall be considered energized with potentially fatal voltages.
Workers shall understand that:
• Electrical shock will occur when a person, by either direct contact or indirect contact with an energized electrical conductor, provides a path for the flow of electricity to a grounded object or to the ground itself. Simultaneous contact with two energized conductors’ phase to phase will also cause electric shock that may result in serious or fatal injury.
• Electrical shock may occur because of ground fault when a person stands near a grounded object.
• In the event of a downed energized electrical conductor or energized grounded object, there exists the hazard of step potential.
• If the minimum approach distance cannot be maintained during operations, the electrical system owner/operator shall be advised, and an electrical hazard abatement plan implemented before any work is performed in proximity to energized electrical conductors.
Non-conductive Equipment
• Non-conductive equipment includes: wood or fiberglass tools, ropes and wood or fiberglass ladders. THESE TOOLS BECOME CONDUCTIVE IF THEY ARE WET OR DIRTY!! A rope or tool that is wet or that is contaminated to the extent that its insulating capacity is impaired, is not to be considered insulated, and may not be used near exposed energy lines. Footwear, including lineman's overshoes or those with electrical-resistant soles, shall not be considered as providing any measure of safety from electrical hazards. Rubber gloves, with or without leather, or other protective covering, shall not be considered as providing any measure of safety from electrical hazards. Ladders, platforms, booms, buckets, or any part of an aerial device or piece of equipment shall not be allowed to make contact or violate minimum approach distances with energized electrical conductors, poles, or similar conductive objects.
• Equipment brought into contact with energized electrical conductors shall be considered energized. Contact by people and/or equipment shall be avoided. Operations shall be suspended when adverse weather conditions or emergency conditions develop involving energized electrical conductors. Electrical system owners/operators shall be notified immediately.
• Workers performing operations after a storm or under similar conditions shall be trained in the special hazards associated with this type of work.
Elements of Electricity
• Electricity is the flow of electrons which is referred to as current. Current is measured by volts, amps and ohms.
• Each individual conductor wire is known as a phase. Electricity is generated and conducted as three phases.
Volts: The force propelling the flow of electrons or the electrical pressure is measured in voltage, or volts for short.
• The higher the voltage is, the greater the risk of arcing and overcoming resistance.
• Twelve volts of electricity is enough pressure to overcome the resistance of human skin. A car battery is twelve volts.
• The common household plug is 110 volts.
• All primary wires and substation facilities are thousands of volts or kv.
• All OSHA safety requirements are listed by voltage phase to phase which is more than phase to ground.
Amps
The rate at which electricity moves or the flow of electricity is called amperes, or amps for short.
• The higher the amps, the more electricity is moving.
• One tenth of an amp can cause ventricular fibrillation, which can cause death.
• A 60-watt light bulb uses one half to one amp.
• All conductors including communication cables and lines contain enough amps to kill.
Ohms: When an object or substance limits the flow of current, this property is called resistance. Resistance is measured in ohms.
• The higher the ohms are, the lower the electrical current.
• Materials with a high level of resistance are called insulators. Common insulators include: plastics, rubber, and porcelain. These materials do not allow electricity to pass through them easily.
• Materials with a low level of resistance are used as conductors. The most common are aluminum and copper. One of the minerals with the lowest resistance is gold; therefore, gold jewelry can be an electrical hazard.
• It is impossible to predict the resistance of an electrical contact.
Completing a Circuit
In order to flow, electricity needs a "path to ground". Providing a path to ground is known as "completing a circuit".
• Materials with a low level of resistance are called conductors. Common conductors include water, most metals, and the human body. Electricity can pass easily through these materials under almost all conditions.
• Any conductive object can be a path to ground. Conductive objects include, but are not limited to: metal objects, trees, branches, fences, guide rails, utility poles, uninsulated equipment and uninsulated sections of insulated equipment.
• Nonconductive objects and tools can become conductive if they are wet or dirty.
A conductive path between two energized wires creates a DEAD SHORT. This can create fireballs, surges and downed lines.
Electrical Contact
There are two basic kinds of electrical contact; direct contact and indirect contact.
• Direct contact occurs when some part of a worker's body comes into contact with an energized electrical conductor. Possible causes are falling or swinging into the conductors. This can also occur in storm situations when energized conductors are damaged by storm and are near or on the ground.
• Indirect contact occurs when some part of a worker's body comes into contact with a conductive object that is in contact with an energized conductor. Conductive objects include but are not limited to: tree branches, conductive tools, wet or dirty tools including ropes, utility poles and damaged electric facilities.
ALL WIRES, CONDUCTORS AND COMMUNICATION CABLES ARE TO BE CONSIDERED AND TREATED AS ENERGIZED
Electrical Hazards on the Ground
Electrical hazards are not limited to workers aloft; workers on the ground can be exposed to electrical contact.
• Uninsulated equipment can become energized.
• A tree falling and coming in contact with conductors can become energized.
• A wet rope coming into contact with conductors can become energized.
• Utility poles can become energized when there is damage to the facilities.
• Fallen wires can be energized and therefore energize fences, guard rails and equipment. When electrical current has a path to ground, the current spreads in the ground in expanding circles of lessening voltage. This is known as step potential. A person taking normal step
within this energized zone has the hazard of creating a path to ground between different voltage levels.
• ALWAYS ASSUME THAT FALLEN WIRES ARE ENERGIZED!!
• If the crew encounters a downed power line, immediately secure the area and notify the supervisor and the utility.
• Protect the area from all unauthorized entry, especially children and the public. The crew shall remain on site until the utility personnel release them.
Minimum Approach Distance (MAD):
Workers should remain ten feet from energized conductors whenever possible. All workers shall maintain the following minimum approach distances from all energized conductors:
Overview of Electrical System and Electrical Apparatus Identification
• Power plants generate electricity in three phases. The three-phase power leaves the generator and enters a transmission substation at the power plant. This substation uses large transformers to convert the generator's voltage up to high voltages for transportation on the transmission grid.
• The transmission lines or transmission grid are conductive wires on towers or large poles, that conduct the electricity long distances. Typical voltages for transmission are 130,000 to 770,000 volts.
• The electricity comes off the transmission grid and is stepped-down to the distribution grid. The place where the conversion from "transmission" to "distribution" occurs is in a power substation. A power substation typically does two or three things:
1. It has transformers that step transmission voltages down to distribution voltages.
2. It has a "bus" that can split the distribution power off in multiple directions.
3. It often has circuit breakers and switches so that the substation can be disconnected from the transmission grid, or separate distribution lines can be disconnected from the substation, when necessary.
• The regulator banks are located along the line, either underground or in the air. They regulate the voltage on the line to prevent under-voltage and over-voltage conditions.
• There are switches that allow this regulator bank to be disconnected for maintenance when necessary.
• Typically, three phase wires leave the substation, with taps of one or two phases running off the three-phase. These primary voltage wires are generally 4,000 to 34,000 volts. There are transformer drums attached to the pole, which step down the primary voltage to 240 volts to secondary lines/service drops.
• In many suburban neighborhoods, the distribution lines are underground and there are green transformer boxes.
Substation Safety
Utility company security procedures will be followed when working in substations. Required Personal Protective equipment for working inside substations includes: Hard Hat, Safety Glasses, Steel Toed Work Boots, and FR clothing. FR clothing MUST be the outer layer of clothing. Reflective vests are not FR and must be removed before entering substations. Substation gates must remain locked unless a worker is assigned to guard the gate.
If any damage to the facilities is encountered or caused, the utility SHALL be notified immediately. Minimum approach distances SHALL be maintained for all electrical equipment. It may be necessary to assign a worker to watch the equipment during operation, to maintain minimum approach. If this is necessary, the assigned worker shall not be performing any other work while performing this duty. Never carry tools, materials or equipment above shoulder level within substations. When driving vehicles or equipment within substations, the operator shall not drive over cable covers, underground cables, or near substation equipment. Do not drive under energized conductors unless minimum separation can be maintained. Drive less than ten miles per hour within substations. Workers shall not come in contact with vehicles or equipment that are in proximity to energized facilities.
Working in Proximity to Electrical Hazards
An inspection shall be made by a qualified arborist to determine whether an electrical hazard exists before: climbing, otherwise entering, or performing work in or on a tree.
• Only qualified line-clearance arborists or qualified line-clearance arborist trainees shall be assigned to work where an electrical hazard exists. Qualified line-clearance arborist trainees shall be under the direct supervision of qualified line-clearance arborists.
• A second qualified line-clearance arborist or line-clearance arborist trainee shall be within visual or voice communication, during line-clearing operations. This applies when aloft, if an arborist must approach closer than 10 feet (3.05 m) to any energized electrical conductor more than 750 volts (primary conductor) or when branches or limbs are being removed. (If they cannot first be cut, with a nonconductive pole pruner/pole saw to sufficiently clear electrical conductors, to avoid contact.) Roping is required to remove branches or limbs from such electrical conductors.
• Qualified line-clearance arborists and line-clearance arborist trainees shall maintain minimum approach distances for qualified arborists, from energized electrical conductors. All other arborists and other workers shall maintain a minimum approach distance, for non- qualified
arborists, from energized electrical conductors.
• Branches hanging on an energized electrical conductor shall be removed using nonconductive equipment, only by a qualified line-clearance arborist or line-clearance arborist trainee. The tie-in position should be above the work area and located in such a way that a slip would swing the arborist away from any energized electrical conductor or other identified hazard. While climbing, the arborist should climb on the side of the tree that is away from energized electrical conductors while maintaining the required distances. Footwear, including lineman's overshoes or those with electrical-resistant soles, shall not be considered as providing any measure of safety from electrical hazards. Rubber gloves, with or without leather or other protective covering, shall not be considered as providing safety from electrical hazards.
• A rope or tool that is wet, or that is contaminated to the extent that its insulating capacity is impaired is not to be considered insulated and may not be used near exposed energy lines.
Ladders, platforms, booms, buckets, or any part of an aerial device shall not be allowed to make contact or violate minimum approach distances, with energized conductive objects.
• Aerial devices with attached equipment brought into contact with energized electrical conductors, shall be considered energized. Contact by people and/or equipment shall be avoided.
• Line clearance shall not be performed during adverse weather conditions such as: thunderstorms, high winds, and snow and ice storms. Qualified line-clearance arborists and qualified line-clearance arborist trainees, performing line clearance after a storm or under similar conditions, shall be trained in the special hazards associated with this type of work.
• Line-clearance operations shall be suspended when: adverse weather conditions or emergency conditions develop, involving energized electrical conductors. Electrical system owners/operators shall be notified immediately. Manufacturers Manuals and OSHA regulations SHALL be used for training on the SAFE use, maintenance and repair of all equipment.
Electrical Hazard Recognition
Each employee shall be trained to recognize and be qualified to work within proximity to electrical hazards that are applicable to the employee's assignment.
All overhead and underground electrical conductors and all communication wires and cables shall be considered energized with potentially fatal voltages.
Workers shall understand that:
• Electrical shock will occur when a person, by either direct contact or indirect contact with an energized electrical conductor, provides a path for the flow of electricity to a grounded object or to the ground itself. Simultaneous contact with two energized conductors’ phase to phase will also cause electric shock that may result in serious or fatal injury.
• Electrical shock may occur because of ground fault when a person stands near a grounded object.
• In the event of a downed energized electrical conductor or energized grounded object, there exists the hazard of step potential.
• If the minimum approach distance cannot be maintained during operations, the electrical system owner/operator shall be advised, and an electrical hazard abatement plan implemented before any work is performed in proximity to energized electrical conductors.
Non-conductive Equipment
• Non-conductive equipment includes: wood or fiberglass tools, ropes and wood or fiberglass ladders. THESE TOOLS BECOME CONDUCTIVE IF THEY ARE WET OR DIRTY!! A rope or tool that is wet or that is contaminated to the extent that its insulating capacity is impaired, is not to be considered insulated, and may not be used near exposed energy lines. Footwear, including lineman's overshoes or those with electrical-resistant soles, shall not be considered as providing any measure of safety from electrical hazards. Rubber gloves, with or without leather, or other protective covering, shall not be considered as providing any measure of safety from electrical hazards. Ladders, platforms, booms, buckets, or any part of an aerial device or piece of equipment shall not be allowed to make contact or violate minimum approach distances with energized electrical conductors, poles, or similar conductive objects.
• Equipment brought into contact with energized electrical conductors shall be considered energized. Contact by people and/or equipment shall be avoided. Operations shall be suspended when adverse weather conditions or emergency conditions develop involving energized electrical conductors. Electrical system owners/operators shall be notified immediately.
• Workers performing operations after a storm or under similar conditions shall be trained in the special hazards associated with this type of work.
Elements of Electricity
• Electricity is the flow of electrons which is referred to as current. Current is measured by volts, amps and ohms.
• Each individual conductor wire is known as a phase. Electricity is generated and conducted as three phases.
Volts: The force propelling the flow of electrons or the electrical pressure is measured in voltage, or volts for short.
• The higher the voltage is, the greater the risk of arcing and overcoming resistance.
• Twelve volts of electricity is enough pressure to overcome the resistance of human skin. A car battery is twelve volts.
• The common household plug is 110 volts.
• All primary wires and substation facilities are thousands of volts or kv.
• All OSHA safety requirements are listed by voltage phase to phase which is more than phase to ground.
Amps
The rate at which electricity moves or the flow of electricity is called amperes, or amps for short.
• The higher the amps, the more electricity is moving.
• One tenth of an amp can cause ventricular fibrillation, which can cause death.
• A 60-watt light bulb uses one half to one amp.
• All conductors including communication cables and lines contain enough amps to kill.
Ohms: When an object or substance limits the flow of current, this property is called resistance. Resistance is measured in ohms.
• The higher the ohms are, the lower the electrical current.
• Materials with a high level of resistance are called insulators. Common insulators include: plastics, rubber, and porcelain. These materials do not allow electricity to pass through them easily.
• Materials with a low level of resistance are used as conductors. The most common are aluminum and copper. One of the minerals with the lowest resistance is gold; therefore, gold jewelry can be an electrical hazard.
• It is impossible to predict the resistance of an electrical contact.
Completing a Circuit
In order to flow, electricity needs a "path to ground". Providing a path to ground is known as "completing a circuit".
• Materials with a low level of resistance are called conductors. Common conductors include water, most metals, and the human body. Electricity can pass easily through these materials under almost all conditions.
• Any conductive object can be a path to ground. Conductive objects include, but are not limited to: metal objects, trees, branches, fences, guide rails, utility poles, uninsulated equipment and uninsulated sections of insulated equipment.
• Nonconductive objects and tools can become conductive if they are wet or dirty.
A conductive path between two energized wires creates a DEAD SHORT. This can create fireballs, surges and downed lines.
Electrical Contact
There are two basic kinds of electrical contact; direct contact and indirect contact.
• Direct contact occurs when some part of a worker's body comes into contact with an energized electrical conductor. Possible causes are falling or swinging into the conductors. This can also occur in storm situations when energized conductors are damaged by storm and are near or on the ground.
• Indirect contact occurs when some part of a worker's body comes into contact with a conductive object that is in contact with an energized conductor. Conductive objects include but are not limited to: tree branches, conductive tools, wet or dirty tools including ropes, utility poles and damaged electric facilities.
ALL WIRES, CONDUCTORS AND COMMUNICATION CABLES ARE TO BE CONSIDERED AND TREATED AS ENERGIZED
Electrical Hazards on the Ground
Electrical hazards are not limited to workers aloft; workers on the ground can be exposed to electrical contact.
• Uninsulated equipment can become energized.
• A tree falling and coming in contact with conductors can become energized.
• A wet rope coming into contact with conductors can become energized.
• Utility poles can become energized when there is damage to the facilities.
• Fallen wires can be energized and therefore energize fences, guard rails and equipment. When electrical current has a path to ground, the current spreads in the ground in expanding circles of lessening voltage. This is known as step potential. A person taking normal step
within this energized zone has the hazard of creating a path to ground between different voltage levels.
• ALWAYS ASSUME THAT FALLEN WIRES ARE ENERGIZED!!
• If the crew encounters a downed power line, immediately secure the area and notify the supervisor and the utility.
• Protect the area from all unauthorized entry, especially children and the public. The crew shall remain on site until the utility personnel release them.
Minimum Approach Distance (MAD):
Workers should remain ten feet from energized conductors whenever possible. All workers shall maintain the following minimum approach distances from all energized conductors:
Overview of Electrical System and Electrical Apparatus Identification
• Power plants generate electricity in three phases. The three-phase power leaves the generator and enters a transmission substation at the power plant. This substation uses large transformers to convert the generator's voltage up to high voltages for transportation on the transmission grid.
• The transmission lines or transmission grid are conductive wires on towers or large poles, that conduct the electricity long distances. Typical voltages for transmission are 130,000 to 770,000 volts.
• The electricity comes off the transmission grid and is stepped-down to the distribution grid. The place where the conversion from "transmission" to "distribution" occurs is in a power substation. A power substation typically does two or three things:
1. It has transformers that step transmission voltages down to distribution voltages.
2. It has a "bus" that can split the distribution power off in multiple directions.
3. It often has circuit breakers and switches so that the substation can be disconnected from the transmission grid, or separate distribution lines can be disconnected from the substation, when necessary.
• The regulator banks are located along the line, either underground or in the air. They regulate the voltage on the line to prevent under-voltage and over-voltage conditions.
• There are switches that allow this regulator bank to be disconnected for maintenance when necessary.
• Typically, three phase wires leave the substation, with taps of one or two phases running off the three-phase. These primary voltage wires are generally 4,000 to 34,000 volts. There are transformer drums attached to the pole, which step down the primary voltage to 240 volts to secondary lines/service drops.
• In many suburban neighborhoods, the distribution lines are underground and there are green transformer boxes.
Substation Safety
Utility company security procedures will be followed when working in substations. Required Personal Protective equipment for working inside substations includes: Hard Hat, Safety Glasses, Steel Toed Work Boots, and FR clothing. FR clothing MUST be the outer layer of clothing. Reflective vests are not FR and must be removed before entering substations. Substation gates must remain locked unless a worker is assigned to guard the gate.
If any damage to the facilities is encountered or caused, the utility SHALL be notified immediately. Minimum approach distances SHALL be maintained for all electrical equipment. It may be necessary to assign a worker to watch the equipment during operation, to maintain minimum approach. If this is necessary, the assigned worker shall not be performing any other work while performing this duty. Never carry tools, materials or equipment above shoulder level within substations. When driving vehicles or equipment within substations, the operator shall not drive over cable covers, underground cables, or near substation equipment. Do not drive under energized conductors unless minimum separation can be maintained. Drive less than ten miles per hour within substations. Workers shall not come in contact with vehicles or equipment that are in proximity to energized facilities.
Working in Proximity to Electrical Hazards
An inspection shall be made by a qualified arborist to determine whether an electrical hazard exists before: climbing, otherwise entering, or performing work in or on a tree.
• Only qualified line-clearance arborists or qualified line-clearance arborist trainees shall be assigned to work where an electrical hazard exists. Qualified line-clearance arborist trainees shall be under the direct supervision of qualified line-clearance arborists.
• A second qualified line-clearance arborist or line-clearance arborist trainee shall be within visual or voice communication, during line-clearing operations. This applies when aloft, if an arborist must approach closer than 10 feet (3.05 m) to any energized electrical conductor more than 750 volts (primary conductor) or when branches or limbs are being removed. (If they cannot first be cut, with a nonconductive pole pruner/pole saw to sufficiently clear electrical conductors, to avoid contact.) Roping is required to remove branches or limbs from such electrical conductors.
• Qualified line-clearance arborists and line-clearance arborist trainees shall maintain minimum approach distances for qualified arborists, from energized electrical conductors. All other arborists and other workers shall maintain a minimum approach distance, for non- qualified
arborists, from energized electrical conductors.
• Branches hanging on an energized electrical conductor shall be removed using nonconductive equipment, only by a qualified line-clearance arborist or line-clearance arborist trainee. The tie-in position should be above the work area and located in such a way that a slip would swing the arborist away from any energized electrical conductor or other identified hazard. While climbing, the arborist should climb on the side of the tree that is away from energized electrical conductors while maintaining the required distances. Footwear, including lineman's overshoes or those with electrical-resistant soles, shall not be considered as providing any measure of safety from electrical hazards. Rubber gloves, with or without leather or other protective covering, shall not be considered as providing safety from electrical hazards.
• A rope or tool that is wet, or that is contaminated to the extent that its insulating capacity is impaired is not to be considered insulated and may not be used near exposed energy lines.
Ladders, platforms, booms, buckets, or any part of an aerial device shall not be allowed to make contact or violate minimum approach distances, with energized conductive objects.
• Aerial devices with attached equipment brought into contact with energized electrical conductors, shall be considered energized. Contact by people and/or equipment shall be avoided.
• Line clearance shall not be performed during adverse weather conditions such as: thunderstorms, high winds, and snow and ice storms. Qualified line-clearance arborists and qualified line-clearance arborist trainees, performing line clearance after a storm or under similar conditions, shall be trained in the special hazards associated with this type of work.
• Line-clearance operations shall be suspended when: adverse weather conditions or emergency conditions develop, involving energized electrical conductors. Electrical system owners/operators shall be notified immediately. Manufacturers Manuals and OSHA regulations SHALL be used for training on the SAFE use, maintenance and repair of all equipment.
