1. Arc Flash Safety
Qualified Persons Working On Or Near Energized Equipment
Welcome to this training session about arc flash. In this session we’ll talk about the hazards and risks of working on or near energized electrical equipment. We’ll also discuss the procedures for preventing an arc flash accident, and how to protect yourself from the hazards of an arc flash.

2. Objectives You will be able to:
Identify the causes and risks of arc flash
Implement safe work procedures
Identify and wear appropriate PPE
Respond to an arc flash
By the end of the training session, you will be able to:
Identify the causes and risks of arc flash;
Implement procedures to prevent arc flash;
Identify and wear the proper personal protective equipment, or “PPE”; and
Respond appropriately to an arc flash incident.

3. What Is an Arc Flash? Electrical short circuit— or arc—through the air
Concentrated energy explodes outward
High-intensity flash
Instantaneous arc blast pressure wave
Superheated ball of gas—melts metal, burns clothes and skin
An arc flash is a high-amperage short circuit that sends an electric current through the air. It occurs when an electric current flows between separate energized conducting surfaces, such as when circuit breakers and disconnects are opened and closed, when energized equipment is touched with a tool, or when equipment fails. Most electrical arc flash injuries do not occur in the presence of high-voltage (above 600 volts) electrical currents. Low voltage equipment sources (under 600 volts) account for most electrical arc flash occurrences. However, high-voltage incidents can be the most catastrophic.
In an arc flash incident, an enormous amount of concentrated radiant energy emanates outward from the source of the arc, along with extremely hot gases (arc plasma).
A high-intensity flash is produced that can be bright enough to damage your eyesight.
An instantaneous and powerful pressure wave that radiates from the source of the arc flash is also produced. The wave can cover several feet in half a second.
The blast can send loose material like pieces of damaged equipment, tools, molten metal, and other objects flying through the air.
The thermal blast generates a superheated ball of gas that can severely burn the human body and even melt metal.

4. Arc Flash Effects Severe burns Hearing loss
Fireball destroys skin and tissue
Heat blast can extend several feet from source
Burns from hot surfaces, projectiles, and fireball
Hearing loss
Extensive damage to equipment
Punctures and lacerations
Electrical burns, often severe, are a common injury from arc flash incidents.
The flash itself can reach 35,000 degrees Fahrenheit, and the resultant fireball will severely burn skin and underlying tissue.
The heat blast can cause severe burns several feet from the source.
Severe burns can also occur from contacting surfaces or being hit by super-heated projectiles or when clothing or equipment catches fire from the thermal blast.
The arc blast pressure wave can damage your hearing.
Equipment that is part of or exposed to the arc blast is often severely damaged.
Also, flying debris can puncture or lacerate the skin.

5. Causes of Arc Flash Dropped tools
Accidental contact with electrical systems
Improper work procedures
Insulation failure
Voltage testing with inappropriate instrument
Inattentiveness
You can be severely injured from an arc flash without touching the energized equipment! Workers have been injured while they were several feet away from the arc flash. The causes of an arc flash include:
Tools dropped on conductors, circuit breakers, or other energized parts, which can cause a short-circuit;
Accidental contact with electrical systems, such as a worker accidentally touching an energized conductor thought to be de-energized;
Improper work procedures, such as working on energized equipment when it should have been de-energized or locked out;
Insulation failure where the fault current’s magnetic effect causes conductors to separate, producing an arc;
Testing electrical equipment with inappropriate instruments; and
Inattentiveness to the risks posed by energized equipment.

6. Causes of Arc Flash (cont.)
Buildup of dust, impurities, and corrosion on insulating surfaces
Sparks produced during racking of breakers, replacement of fuses, and closing into faulted lines
Birds or rodents that break leads at connections
Here are some additional causes of arc flash:
Buildup of dust, impurities, and corrosion on insulating surfaces, which can provide a path for current;
Sparks produced during racking of breakers, replacement of fuses, and closing into faulted lines; and
Birds or rodents that snap leads at connections.

7. Arc Flash Exposure Risk
Workers are at higher risk when:
Exposed to energized parts often
Required to perform multiple tasks
Poorly trained
Concentration is broken
The risk of an arc flash and your exposure to it depends on many factors.
There is a higher risk of an arc flash incident when workers are:
Exposed to energized parts repeatedly or for extended periods;
Required to perform several tasks in the same work area during the same operation;
Poorly trained in the specific tasks they must perform; or
Diverted from paying attention to the task at hand.

8. Arc Flash Exposure Risk (cont.)
Risk is lower when:
Clear work practices are established
Training is thorough and up to date
Proper PPE is worn
Equipment is routinely maintained
Workers are alert
The risk of an arc flash is lower when:
Clear work practices are established, such as written procedures and/or hot work permits;
Training is thorough and up to date;
The right PPE is worn at all times that it is required;
Electrical equipment is routinely maintained and inspected; and
Workers are alert to the risks of their tasks.

9. Exercise—Hazards and Risks List 4 arc flash effects
Severe Burns
Hearing Loss
Excessive Damage to Equipment
In this exercise, see if you can remember four arc flash effects. Four effects of arc flash are:
Severe burns,
Hearing loss,
Excessive damage to equipment; and
Puncture wounds and lacerations.
Puncture Wounds and Lacerations

10. Exercise (cont.) List at least 3 causes of arc flash
Dropped Tools
Accidental contact with electrical systems
Improper work procedures
Insulation failure
Voltage testing with inappropriate tool
Buildup of dust, impurities and corrosion
Now, see if you can remember at least three causes of arc flash. The causes of arc flash are:
Dropped tools;
Accidental contact with electrical systems;
Improper work procedures;
Insulation failure;
Voltage testing with inappropriate instrument;
Buildup of dust, impurities, and corrosion on insulating surfaces;
Sparks produced during racking of breakers, replacement of fuses, and closing into faulted lines;
Birds or rodents that break leads at connections; and finally
Worker inattentiveness.
Sparks produced during maintenance
Birds or rodents that break connection leads
Worker Inattentiveness

11. Arc Flash Prevention Allow only qualified persons
De-energize equipment whenever possible
Create safe work conditions
Use proper equipment
The best way to prevent arc flash incidents from occurring is to:
Allow only qualified persons to work on electrical equipment. A qualified person is one who has received documented training in the hazards of working on energized equipment in general and has been trained in the hazards of the particular equipment to be serviced, and the use and proper application of PPE. Again, only a qualified person is permitted to work on live electrical equipment.
De-energize all equipment, if possible, before beginning work.
Create an electrically safe work condition. This is done with engineering controls (such as equipment upgrades) and by following safe work procedures.
And finally, use only equipment that has been designed and certified for the task

12. Safe Work on Energized Parts
Never work on live equipment, except when:
De-energizing introduces additional or increased hazards
It is not feasible to de-energize
The proper training and safety equipment is provided
Never work on live equipment greater than 50 volts except when:
De-energizing or shutdown introduces additional or increased hazards such as cutting ventilation to a workplace with a hazardous atmosphere;
It is not feasible to de-energize because of equipment design or operational limitations, such as when voltage testing is required for diagnostic purposes; or when
The proper training of personnel and personnel protective equipment is provided.

13. 3. Determine and implement protective measures 4. Wear appropriate PPE
Safe Work Practices
1. Review the operation
2. Determine the hazards
3. Determine and implement protective
measures
4. Wear appropriate PPE
5. Know how to respond to an arc flash
incident
Follow these basic safe work practice steps before starting work in a work area with live or energized equipment. Before performing work on live electrical systems or systems where arc flash is a risk, it is recommended that a meeting take place to go over all of these items. Each of these steps will be discussed in following slides:
Review the work operation;
Determine the hazards;
Determine and implement protective measures;
Wear appropriate PPE; and
Know how to respond to an arc flash incident.

14. Safe Work Practices— Review the Operation
Read all warning signs
Read the hot work permit
Match the tools to the operation
Take whatever readings are necessary to quantify the system’s operation
Before starting any work in areas with energized parts, make sure you understand and follow safe work practice procedures. Every electrical operation is a little different. Even if you work in a familiar area, someone else working in the same area may have changed something that affects your safety. So:
Read all the warning signs in the work area about electrical hazards and instructions for protecting yourself from them.
Read all of the requirements of any hot work permit issued for your work on or around live electrical parts and equipment. It may seem tedious, but it could save your life or many years of pain and suffering.
Do an inventory of all tools that will be needed for each operation, and ensure that they are rated for the specified use and in good working condition.
And finally, before wiring on an energized system, take whatever measurements are necessary to ensure the system is operating normally.

15. Safe Work Practices— Determine the Hazards
Identify and inspect energized parts
Respect the flash protection boundary
Identify sharp objects and other obstructions
Identify all environmental hazards
Before starting any work in areas with energized parts, follow these safe work practice procedures:
Identify and inspect all of the energized parts and equipment in your work area, regardless of whether you plan to work on them. Many arc flash incidents occur when tools touch or fall on live electrical equipment adjacent to or below the parts being serviced. In other cases, the cause is faulty or old circuits and connections that were not inspected.
Do not cross an arc flash boundary without wearing all appropriate PPE.
Check your work area for sharp objects and other obstructions that could cause injury or hinder escape and rescue if an arc flash or other electrical accident takes place.
And finally, identify all environmental hazards such as water on the floor, which can create a ground, or oil on the floor, which can ignite or indicate a leak in a oil filled breaker or transformer.

16. Safe Work Practices —The Flash Protection Boundary
Limited approach boundary
Restricted approach boundary
Prohibited approach boundary
The flash protection boundary is the distance from a potential arc source within which the potential incident heat energy could cause at least a second-degree burn.
The limited approach boundary defines a boundary around exposed live parts that may not be crossed by “unqualified” persons unless accompanied by “qualified” persons;
The restricted approach boundary is the area near the exposed live parts that may be crossed only by “qualified” persons using appropriate shock prevention techniques and equipment; and
The prohibited approach boundary is the area near exposed live parts that may be crossed only by “qualified” persons using the same protection as if direct contact with live parts is planned. This is defined by the nominal voltage (standard 120V, 240V, 480V, etc.).

17. Safe Work Practices— Deenergizing and Lockout
Identify all possible sources of energy supply
Open disconnecting device(s)
Verify device is open
Apply lockout/tagout devices
Test voltage—double check instrument rating
Apply grounding devices
Some operations will require certain equipment to be de-energized and locked out before starting any work with energized parts. Follow these general procedures, and the specific procedures of the lockout/tagout program:
Find all possible sources of energy supply.
Open disconnecting device(s).
Verify device is open.
Apply lockout/tagout devices wherever required.
Test the voltage using only testing equipment that is in perfect working condition and that is rated for the equipment testing being performed.
And apply appropriate grounding devices.

18. Safe Work Practices— Wear Appropriate PPE
Helmet or headgear
Arc-rated face shield
Safety glasses
Rated gloves
Rated shoes/boots
Rated flame-resistant clothing
No metal button, clasps, or zippers!
Helmet or headgear
Arc-rated face shield
Safety glasses
Rated gloves
Rated shoes/boots
Rated flame-resistant clothing
No metal button, clasps, or zippers!

19. Explosion Response Procedure
Turn off the power
Extinguish flames
Call for help
Begin CPR and first aid, if trained
If there is an arc flash incident and you are uninjured and able to respond, take the following measures to minimize further damage or injury:
Turn off the power supply if you are trained and able to do so.
Extinguish flames on a person first, then on equipment if the fire is incipient (early stages and small).
Call for help—sound the alarm.
And finally, begin CPR immediately if a co-worker is injured and is not breathing, and administer first aid if you are trained to do so. Before beginning CPR, be sure there are no serious burn injuries to the chest region.

20. Take Other Precautions
Only qualified persons
Wear only nonconductive apparel—no jewelry
Work area must be illuminated
No conductive liquids near electrical work or equipment
Do not defeat electrical interlocks
Double-check for the right tools
Follow safe work practices for working around electricity.
Only qualified persons are allowed to work on or near exposed electrical equipment or wiring.
Wear the right protective equipment. Don’t wear any clothing that can conduct electricity. This includes anything with metal, such as metal-rimmed glasses, jewelry, or wire-mesh gloves.
The work area should be well-illuminated so that you can see if there are any electrical hazards present.
Don’t use conductive liquids such as water—or for that matter, any conductive items—anywhere near exposed electrical equipment.
Do not defeat or try to circumvent electrical interlock devices.
And finally, double check to make sure you are using the right tools rated for the job you are doing.

21. Warning Labels Placed on all equipment with potential arc flash hazard
Warning labels are placed on all equipment that poses a potential arc flash hazard. The current standard requires only that the label state the existence of an arc flash hazard.

22. Report—and Don’t Use— Damaged Equipment
Stop using and report:
Broken or missing covers
Damaged tools
Damaged equipment
Improper equipment placement
Damaged equipment can result in serious electrical hazards. Stop using, and report to your supervisor:
Any damaged electrical covers on electrical panels, junction boxes, and other equipment where live electrical parts and wiring may be exposed;
Damaged tools that may expose live electrical parts and wiring to a person;
Damaged equipment, such as circuit breakers, connectors, switches; or
Improper equipment placement such as an extension cord over energized equipment.

23. What are the 5 steps to safe work practices?1
Review the operation Determine the hazards Determine and implement protective measures Wear appropriate PPE Know how to respond to an arc flash incident 2 3 4
In this exercise, see if you can remember the 5 steps to safe work practices. They are:
Review the work operation;
Determine the hazards;
Determine and implement protective measures.
Wear appropriate PPE; and
Know how to respond to an arc flash incident. 5

24. Inspect equipment and work areas for arc flash hazards and risks
Human error a common cause of arc flash
De-energize whenever possible
Follow safe work practices
Wear all required PPE
Report—and don’t use—damaged equipment and tools
Never underestimate the risks and hazards of an arc flash associated with working on energized equipment. The long-term physical and emotional costs of ignoring the hazards and not following safe work practices are high and often permanent.
Here are a few key points to remember when working with energized electrical equipment.
Always inspect equipment and work areas for arc flash hazards and risks each time you enter an area with live electrical equipment. Keep an eye out for arc flash warning labels.
Human error is a major cause of arc flash incidents, such as:
Dropped tools, contact with an electrical part, wrong test equipment, and improper work practices.
To prevent arc flash, always de-energize and lock out equipment whenever possible.
Follow safe work practices without fail, and do not deviate from them at all. They could save your life, and years of pain and suffering.
Wear all required PPE—make sure it is in excellent working condition and rated for the specific use that your work calls for.
And finally, always report—and don’t use—damaged electrical equipment, testing equipment, and other tools.
Give trainees the quiz.