Arc Flash Assessment
The Importance of an Arc Flash Assessment
By Steve Hudgik
An arc flash assessment determines the potential for an arc flash (electrical arc) and the possible intensity of that arc flash. This is critical information needed by anyone who will be working on or near energized electrical parts, switches, breakers or equipment.
In what is known as the General Duty Clause OSHA requires all employers to "furnish to each of his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees."
To do this the employer needs to know if a hazard exists and the extent of that hazard. An arc flash assessment provides this information.
NESC rule 410A3 states: "Effective January 1, 2009, the employer shall ensure that an assessment is performed to determine potential exposure to an electric arc for employees who work on or near energized parts or equipment. If the assessment determines a potential employee exposure greater than 2 cal/cm2 exists, the employer shall require the employee to wear clothing or a clothing system that has an effective rating at least equal to the anticipated level of arc energy."
Although OSHA has not adopted this rule, the General Duty Clause results in compliance with 410A3 being required by OSHA. To comply with this rule an arc flash assessment is needed to determine the potential level of exposure, and thus the required PPE.
In addition, the latest version of NFPA 70E (2012) requires that exposure or PPE information be posted as a part of the arc flash label. An arc flash assessment is required in order to determine this information.
The arc flash assessment is also the source of the information you'll need to provide proper arc flash safety training, as well as for selecting the right tools for safely working on electrical equipment.
Real-world advice and insight into preventing arc flash accidents.
To summarize the reasons for doing an arc flash assessment:
- Comply with NESC 410A3 and the OSHA General Duty Clause
- Provides information required to be on arc flash labels
- Provides for the correct selection of (PPE)
- Allows complete and appropriate training to be provided
- Identifies the appropriate tools needed for working on energized equipment
DuraLabel printers work with all of the software packages used to conduct an arc flash assessment. With a DuraLabel printer you'll easily be able to make fully compliant arc flash labels. Plus DuraLabel is the only printer supplier that has over-sized arc flash die-cuts, giving you the ability to make highly visible arc flash labels. Call 1-888-326-9244 today and ask about DuraLabel Arc Flash Labeling Kits.
Arc Flash Assessment Methods
Some companies have the expertise in-house to conduct an arc flash assessment. In-house engineers familiar with the IEEE 1584-2002 & 1584a 2004 standards can perform the necessary calculations themselves or use arc flash calculation software.
Free tools such as the Duke Power Heat Flux Calculator are available to perform the calculations. There are also a number of commercial software packages that are available. These are more sophisticated than the free Duke Power software, and in some circumstances they better correlate with the real world, and they will provide more information as well as providing one-line diagrams. Just search Google for "arc flash software."
The NFPA 70E code provides for a table method of determining the arc flash hazard level. Use Table130.7(C)(11) from NFPA 70E. However, be aware that there are some limitations to the tables. There are some circumstances in which the tables may not be applicable.
The easiest way to conduct an arc flash assessment is to hire an outside service. Consultants offer Arc Flash Assessment Services in which they will take care of everything from conducting the arc flash analysis to applying the arc flash labels. In addition to determining the status of electrical equipment, most will also make recommendations for modifications to mitigate arc flash. Many consultants can even provide the training your staff will need.
However your arc flash assessment is conducted, one of the end results is the printing and application of arc flash labels. Many arc flash consultants and service providers use DuraLabel printers. Whether your arc flash labels are printed bv an outside service or in-house, for duability, clarity and long-life effectiveness, be sure your arc flash labels are made with a DuraLabel printer. For more information about DuraLabel printers and arc flash labeling supplies, call 1-888-326-9244. Ask about the advanced technology DuraLabel TORO printer (the only four inch, standalone, fully portable arc flash label printer) and request a set of free sample labels. Call today, you'll be glad you did.