What is an Arc Flash
An arc flash is the light and heat that is produced as part of an arc fault, which is a type of electrical explosion or discharge that results from a low-impedance connection or another voltage phase in an electrical system. SEAM Group offers a service called arc flash hazard analysis, where our engineering professionals determine the amount of energy generated in an arc flash incident and provide information to keep employees safe at work.
Jay Smith, Director of Electrical Safety Services at SEAM Group, joined us during our recent webinar to dive into the details when it comes to arc flashes and what organizations can do in order to comply with current regulations.
What to Know About Arc Flash Hazards
Complying with NFPA 70E
Regardless of the industry you work in, if you have employees that are exposed to or work around energized, electrical equipment, it’s important that you implement NFPA 70E — an industry-recognized safety standard of the National Fire Protection Association that covers electrical safety requirements for employers and employees in compliance with the Occupational Safety and Health Administration (OSHA).
There are an estimated 30,000 arc flash incidents per year, resulting in an estimated 7,000 burn injuries and 400 fatalities annually. More than 80% of these fatalities are due to burns and not electrocution. NFPA 70E is revised every three years in order to further reduce these incidents as it’s impossible to predict how an arc flash will behave.
Difficulties of Implementing NFPA 70E
The most difficult part of implementing NFPA 70E to protect personnel from arc flash dangers is the culture change required — whether that’s the culture of your management or your end-users, such as electricians or maintenance staff.
Culture change is difficult to achieve because it’s time-consuming and can be quite difficult. Everyone throughout your facility and at all levels has to understand and be willing to change. The most difficult part about culture change is that you can’t pay someone to do it for you — it will take time for everyone to buy-in.
When it comes to changing your culture, you’ll have to involve the key people in your company. This may include individuals from safety management, engineering, maintenance, and maybe even your end-users. Getting your key people on board early in the process will make it easier to bring everyone else on board later.
One of your key people might be an employee with more than 30 years of experience, who has an in-depth understanding of arc flash dangers and electrical systems. This is an example of someone you’ll want to get involved in the culture change process. If you get him or her on board, everyone under them is more likely to follow suit.
It’s important to make sure your people understand why you’re doing this. Training will be key to the process. Be sure to document that they know what they’re doing, the policies they should be following, the gear they’re wearing, etc. Everything needs to be verifiable. If an incident occurs, you want to be able to look back and say that all your employees were qualified to do the work and provide their qualifications.
Having a lockout/tagout procedure in place does not exempt you from NFPA 70E. The actual process of performing an electrical lock-out is considered hazardous by both OSHA and NFPA 70E.
In order to perform a lock-out, a meter is tested on a known live circuit to make sure it’s functioning properly. Once it’s been de-energized, it is then tested again to make sure it has been de-energized properly and that no other power source is feeding it. The meter is then tested on another live circuit to ensure that it didn’t malfunction during verification. This test exposes you to hazardous energy, which is why even though you’ve taken the important step of implementing a lockout/tag-out procedure, you’re still not exempt from the law.
Incident Energy Analysis
An incident energy analysis is a newer term for an arc flash hazard assessment. The primary goal of an incident energy analysis is to identify the hazards you’re potentially facing and engineer them out of your system. If they’re unable to be removed, then the goal is to get them to a point where they’re safely manageable.
The Three Phases of Incident Energy Analysis
1. Data Collection
Data collection is the first step in the incident energy analysis process. A team must come into your facility to gather information. Data collection is a full autopsy of every fuse, breaker, and wire in the building. It is not enough to work with someone who tells you to send them your current drawings and that they’ll send you corresponding labels in return. An incident energy analysis cannot be done without a team collecting data at the site. There is also a false notion that you need pre-existing drawings in order to have an arc flash conducted.
By taking the information recorded in the data collection step, an electrical snapshot of your facility is created. This electrical snapshot is used to find solutions during the engineering phase. During this phase, new and updated drawings of your facility are created. A short-circuit analysis is also conducted, as well as a coordination analysis, where all the fuses and breakers in your facility are verified to be doing what they’re supposed to be doing and in the right order.
Next in the engineering phase, the short circuit analysis of the system will then derive the arcing fault current at each point in the circuit. This arcing fault current along with the protective device tripping curves will be used to determine the incident. The protective device that reacts the quickest to the fault is determined from the system coordination and final incident energy for each point in the circuit is calculated.
Finally, mitigation recommendations can be provided. The information combined during the previous steps allows for the problem to be identified and then fixed. Mitigation can sometimes be very simple, with a single mitigation done upstream being able to affect 50–100 downstream hazards.
During this final phase, labels are applied to equipment and recommendations are categorized in order to get hazards removed.
Poor Arc Flash Information and Labels
There is a lot of bad information about arc flash hazards. Companies are promoting cheap analysis, do-it-yourself processes, and so on. Simple and generic warning labels saying “Potential Arc Flash Hazard: Can Shock, Burn or Cause Death” do not provide enough beneficial information in facilities.
An arc flash assessment is an in-depth, detailed process that can’t be done by simply going through the motions and putting generic labels on everything. Labels should provide detailed information that is specific to the fuse or circuit that is being labeled. This includes the calories at that point in the circuit, the distance of the boundary, the nominal system voltage, the shock boundaries, the equipment name/ID, the name/ID of protective device clearing the fault, and the date the analysis was completed.
Get Expert Assistance with Your Safety Needs
SEAM Group is a leading provider of arc flash hazard analysis and other electrical safety services. In addition to inspecting your equipment and sites for electrical hazards and assisting in their remediation, we provide an online results portal called ViewPoint that allows our clients to drill down into their inspection data, prioritize repairs, and more.