An arc flash risk assessment should be done to:
- identify arc flash hazards
- determine the likelihood of an arc flash, and the injuries it may cause
- determine the severity of the injuries
- determine what protective measures are needed, including personal protective equipment (PPE)
Full Answer
What is an arc flash hazard analysis?
An arc flash study is the evaluation of a workplace facility by an electrical safety expert to determine hazards and risks in relation to electrical systems. The on-site study results in arc flash equipment labeling, fault current and coordination analysis, recommendations for improvements and requirements for proper personal protective ...
Is an arc flash hazard analysis required?
While OSHA doesn’t specifically state that you must perform an arc flash analysis, they do make it clear that electrical safety is required. Under Section 5 of the OSHA Act, it is clear that an employer has a duty to provide employees with a workplace that is ‘free from recognized hazards.’
What information should be included in arc flash study report?
This report will include the following information: A complete description of the study’s results as well as the methodology they used. A breakdown of short-circuit equipment that your company utilizes beyond its ratings and alternatives for the equipment or operations. A list of any equipment that has considerable arc flash hazards.
How often should an arc flash analysis survey be updated?
YES, there is more work that needs to be done. The Standard for Electrical Safety in the Workplace, NFPA 70E states in Article 130.5 that an arc flash study needs to be reviewed every five years or whenever there is a significant change in the electrical system. The five year interval is straight-forward requirement.
Which 3 factors does an arc flash risk assessment determine?
NFPA 70E states that the goal of an arc flash risk assessment is a three-step process: Identify a Hazard. Estimate the Likelihood of Occurrence and the Potential Severity of Injury. Determine If Additional Protective Measures are Needed.
What does an arc flash hazard assessment determine?
An Arc-Flash Hazard Assessment determines the degree to which a worker may be exposed to potential Arc-Flash Hazards and what kind of Personal Protective Equipment (PPE) is required to protect workers from the heat, light, and blast associated with an Arc-Flash accident.
What are the two main types of risk assessments conducted under NFPA 70E?
The severity of an injury also depends on multiple factors and conditions, which is why it's critical to follow proper procedures and conduct an assessment in the first place. The NFPA 70E requires a risk assessment for two types of hazards: shock and arc flash.
What are the two methods stated in NFPA 70E 130.5 for determining the proper arc flash PPE?
To select arc flash PPE, NFPA 70E 130.5(F) lists two methods that may be used incident- energy analysis and arc flash PPE category method. Proper selection of the arc flash PPE requires having an arc rating sufficient for protection from the hazard.
What are the common safety hazards related to arc flash?
The most common injury is a burn from the initial flash or subsequent flame from ignition of clothing. At several feet, burns can be fatal and at 10 feet, serious burns are not uncommon. Heated air and molten metal from arcs can cause ordinary clothing to burst into flame, even if not directly in contact with the arc.
How do you do an arc flash assessment?
The 7 Steps to Complete an Arc Flash AnalysisSTEP 1: Acquire existing as-built documentation. ... STEP 2: Field verification. ... STEP 3: Loading Information. ... STEP 4: Run a Short Circuit Study. ... STEP 5: Selective coordination. ... STEP 6: Arc Flash Evaluation. ... STEP 7: System Evaluation.
What two primary factors determine the available arc flash incident energy?
Although many variables need to be considered when performing incident-energy calculations, two important ones include the arcing short-circuit current (discussed in part 2 of this series) and the arcing time, which defines the duration of the arc flash.
What two things determine according to the NFPA 70E the type of PPE required?
To determine the right PPE, you must pick one of two methods, according to Grainger: an incident energy analysis method or an arc flash PPE category method. You can't use both. The incident energy analysis method calculates “the incident energy and flash boundary” based on tables within the NFPA 70E guidelines.
How are arc flash boundaries determined?
The arc flash boundary is calculated to 1.2 calories/cm2 of incident energy. That's the distance where a worker without appropriate PPE would receive second-degree burns. Sometimes this boundary is the furthest one from the exposed equipment, other times the limited approach boundary is the furthest out.
How is arc flash PPE category determined?
The Arc Flash Personal Protective Equipment (PPE) Category is determined by consulting the PPE tables in article 130.7 of the NFPA 70E standard. PPE categories range from 1 to 4 (with four having the highest incident energy rating and requiring the most protective gear).
What does the NFPA 70E standard now consider first priority when it comes to electrical hazards?
The standard now explicitly states that the first priority must be the elimination of the hazard; each method that follows it is considered less effective than the one before it.
What are the arc flash PPE categories?
Four Categories of Arc Flash PPEPPE Category 1: Minimum Arc Rating 4 cal/cm2PPE Category 2: Minimum Arc Rating 8 cal/cm. ... PPE Category 3: Minimum Arc Rating 25 cal/cm. ... PPE Category 4: Minimum Arc Rating 40 cal/cm.
What is arc flash compliance?
ARC FLASH COMPLIANCE OSHA mandates that employers identify electrical hazards, warn employees about the hazards and provide the proper protection and training regarding the hazards.
What is NFPA 70E arc flash?
NFPA 70E (Arc Flash) requires that only trained and qualified employees can work on or near exposed energized electrical parts and supervise unqualified persons in the vicinity of the hazard. Another requirement of NFPA 70E (Arc Flash) is the implementation of an overall electrical safety program.
How often is arc flash testing required?
every five yearsNFPA 70E states that arc flash hazard calculations need to be reviewed every five years or whenever there is a significant change in the electrical system.
Why is a shock risk assessment performed?
The shock risk assessment must determine the voltage, the shock boundaries, and the required PPE to protect employees from the shock hazard. The arc flash risk assessment first determines if an arc flash hazard exists.
Current
Traditionally, we think of current rating as the rating on the nameplate. For example, a 400-amp panelboard is rated to handle 400 amps of current, the full-load current rating of the equipment. When it comes to arc flash severity, however, the concern is not with the full-load current rating, but with the short-circuit current rating.
Time
Time is another major factor in arc flash severity. The old saying, “Time is of the Essence”, is true with arc flash severity. The longer the fault continues, the more severe the arc flash.
Distance
The third major factor determining arc flash severity is the distance of the worker from ground zero. When an arc flash risk assessment is performed, an arc flash label is placed on the equipment with a value for incident energy. Incident energy determines the severity of an arc flash. The higher the incident energy, the more severe the event.
Take-aways
Arc flash events can be dangerous and deadly. Many factors determine the severity of the event, but three values—current, time, and distance—largely determine the severity.
What is the purpose of reading arc flash labels?
Reading all arc flash labels to determine the level of PPE required and boundary distances.
What is the flash boundary?
Flash Protection (outer boundary): The flash boundary is the farthest established boundary from the energy source. If an arc flash occurred, this boundary is where an employee would be exposed to heat that may cause curable second-degree burns (1.2 calories/cm2). The hazard in this boundary is the heat generated from a flash.
How to eliminate the risk of electrical shock?
Remember: The most effective way to eliminate the risk of electrical shock or arc flash is to de-energize the equipment and not work on equipment that is “live.”
Why are overloaded wires dangerous?
Overloads in an electrical system are hazardous because they can produce heat or an arc. Wires and other components in a system or circuit have a maximum amount of current that they can carry safely. If too many devices are plugged into a circuit, the electrical current will heat the wires to a very high temperature.
Is flash protection the same for all equipment?
Note: These distances are not the same for all types of equipment. Some equipment will have a larger flash protection boundary, while others will have a lesser boundary. Refer to NFPA 70E for boundary distances at given voltage ranges.
When the employee is at the restricted approach boundary, the employee or their tools could touch live parts?
When the employee is at the restricted approach boundary, the employee or their tools could touch live parts if the employee is careless with their movements.
Do you have to wear PPE for arc flash?
Employees must follow the PPE requirements established on arc flash labels. Remember, PPE does not eliminate the electrical hazard or arc flash risk. However, it can help to reduce the severity of an injury.
How to assess arc flash risk?
One method for assessing arc flash risk is to complete an incident energy analysis. This analysis takes into consideration the technical details of the equipment in order to calculate the expected incident energy at a various distances.
How often should arc flash assessments be completed?
These assessments should be completed every five years or any time a major modification is made to the facility that may result in increased risk or severity in the event of an incident. Today, we will explore the basics of arc flash risk assessments as part of a much larger electrical safety initiative.
How many PPE categories are there in NFPA 70E?
NFPA 70E (2018) reduced the number of PPE Categories from five to four, a topic we discussed in our recent blog. Learn more about the four PPE Categories here.
What is the second step in hazard identification?
While hazard identification is one part of the equation, the second step is to identify the likelihood that an adverse event may occur and the severity of injury if it does. Known as assessing risks, this process involves determining how much energy would be released in an arc flash and understanding the severity of injury in such an event.
What is the most important process to recognize, measure, and mitigate?
One of the most important processes to recognize, measure, and mitigate is to complete an Arc Flash Risk Assessment.
What is the first step in risk assessment?
Step 1: Identify Hazards. The first step in a risk assessment is to identify a hazard. Hazards differ from risks; a hazard is a source of potential injury or damage to health while a risk represents the likelihood and severity of injury. Step 1 pertains to the hazard identification (i.e. determining if something may pose a risk when ...
What is incident energy analysis?
Often incident energy analysis is a much more complex way of identifying the potential for risk and severity of injury and is used to determine labeling for the equipment. Completing an incident energy analysis can be completed in multiple ways and a recent article on OHS Online looked at the steps to complete such an analysis, noting the following:
What is the third step of arc flash risk assessment?
The third step of our arc flash risk assessment includes a return trip to your facility for the installation of arc flash labels and four hours of NFPA 70E awareness training. Our installation process is thorough and complete; we will not leave your team with any arc flash labels to apply yourself. We do this to ensure all electrical points are properly labeled. This also allows our team to complete a quality check on the original data collection.
What is the ESS number for arc flash?
ESS offers arc flash risk assessments as well as a variety of training and services anywhere in the United States. For more information, call at (816) 925-0443 or click here to request a quote.
What is step 3 in arc flash?
ESS is the only arc flash provider in the industry that uses step 3 as an opportunity to update your report and single line drawings per the findings during delivery of arc flash labels. In doing this, our field technician will report any changes/updates back to our engineers upon completion of step 3, allowing the engineer time to update your report and drawings as necessary. If needed, new labels can also be created during this phase. Once all reports and drawings are confirmed to be fully accurate, the report and drawings will be provided to your team.
What is the goal of an arc flash assessment?
The goal of an arc flash assessment is to: 1) identify arc flash hazards, 2) estimate the likelihood of occurrence and the potential severity of injury or damage to health and 3) determine if additional protective measures are required.
How often should arc flash studies be done?
In accordance with NFPA 70E standards, arc flash studies should be conducted every five years or whenever a major modification is made to the facility. Keep in mind, even if you haven’t had a major change to your facility within the prescribed five-year window, the energy levels could still change.
How long does it take to complete an arc flash study?
Completing an arc flash study may take about four to six weeks depending on the size of the facility. The governing standard for performing the study is the Institute of Electrical and Electronics Engineers (IEEE) 1584. It provides techniques and calculations for engineers to apply when determining the arc flash hazard distance and the incident energy to which employees could be exposed. The calculations enable facility operators to determine the necessary personal protective equipment (PPE) to address the arc flash hazard.
Why can different engineers evaluate the same system and receive vastly different results?
The likely reason for this is that the engineers did not use the same initial set up and assumptions. To avoid this, the consultant conducting the study should address the specifications with the facility engineer at the onset of the study so the engineer understands the assumptions made by the consultant and why.
Why do utilities need to ramp service?
For instance, if a new development or large industrial park with a huge energy demand is built adjacent to your facility, the utility may need to ramp service to provide power to its new customers. In doing so, the amount of fault current delivered to your facility can change. It’s important to consider external factors such as this to determine how often you need to revisit.
Is arc flash a national standard?
Arc flash and arc blast hazards have been around since electrical power has existed, but they have only recently been addressed in national standards. The National Fire Protection Association’s Standard for Electrical Safety in the Workplace (NFPA70E) states that all facilities must perform an arc flash risk assessment to determine the present degree of hazards, and then apply appropriate equipment labeling.
Is an arc flash risk assessment a living document?
At the end of the day, a successful arc flash risk assessment should be a living document. It is an important part of a facility’s ESWP that should be constantly revisited over time, not just a document that sits on the shelf.
When a review of the Arc Flash Hazard Assessment identifies a change that renders the label inaccurate,?
Note: Where a review of the Arc Flash Hazard Assessment identifies a change that renders the label inaccurate, the label shall be updated.
What is an arc flash?
An Arc Flash is an electrical explosion due to a fault condition or short circuit when either a phase to ground or phase to phase conductor is connected and current flows through the air.
What is the role of OSHA in Arc Flash?
While OSHA tells you "what to do" for Arc Flash, they don't tell you “how to do it”. The role of NFPA 70E, IEEE 1584 and NFPA 70 (NEC) is to provide guidance on "how" to properly implement the OSHA regulations.
What happens when an arc flash happens?
When an Arc Flash happens, it does so without warning and is lightning quick. The result of this violent event is usually destruction of the equipment involved, fire, and severe injury or death to any nearby people. Proper safety and protection measures must be taken to limit the damage from an Arc Flash, which include; conducting an Arc Flash Incident Energy Analysis, Short Circuit Study, Protective Device Coordination Study, Equipment Maintenance, and NFPA 70E required Electrical Safety Training.
Who should be trained to use Arc Flash?
Although the NFPA standard only mentions employees as needing training, Arc Flash Safety Training should be provided to anyone else who may be exposed to an Arc Flash Hazard, including vendors, contractors, or anyone else who may come in contact or close proximity to potentially hazardous electrical equipment.
What is the temperature of an arc blast?
Arc Flashes cause electrical equipment to explode, resulting in an arc-plasma fireball. Temperatures may exceed 35,000° F (the surface of the sun is 9,000° F). These high temperatures cause rapid heating of surrounding air and extreme pressures, resulting in an arc blast. The Arc Flash / Blast will likely vaporize all solid copper conductors which will expand up to 67,000 times its original volume when it is vaporized. The Arc Flash / Blast produces fire, intense light, pressure waves and flying shrapnel.
Why are there misconceptions about arc flash?
There are some common misconceptions about Arc-Flash Hazard Assessments which reduce the effectiveness of the Assessments and can increase electrical hazards . These misconceptions exist because of the confusion about the laws and standards that apply regarding Arc-Flash Hazard Assessments. It is important to note that OSHA (Occupational Safety and Health Administration) may rely on numerous consensus standards to enforce their regulations, and this may vary by state. Further confusion is caused by the various methods used to calculate and quantify Arc-Flash hazards. When deciding to do an Arc-Flash assessment, it is vital to determine what is being offered by a service company and what is required to be OSHA compliant. The goal of this paper is to discuss some of the common misconceptions regarding Arc-Flash Hazard Assessments and clarify what OSHA and NFPA®, the National Fire Protection Association®, actually require.
Is an arc flash required by OSHA?
It is important to remember that performing an Arc-Flash Hazard Assessment is not an option. Arc-Flash Hazard Assessments are required by OSHA and NFPA 70E as a part of an Electrical Hazard Assessment. Arc-Flash Assessments are a serious life safety issue and essential part of a safe and comprehensive electrical safety program. OSHA and NFPA require employers to identify all potential electrical hazards in the workplace such as shock and Arc-Flash Hazards, reduce or eliminate the hazards, train and qualify their employees, and provide them with PPE that will protect them from all hazards. Knowing what OSHA requires and how NFPA 70E can help meet the requirements will not only keep workers safe, but will also increase productivity and profitability for employers.