PowerTest 2012
by James R. White, Shermco Industries, Inc.
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flash. No guidance for this type of equipment was provided in previous editions of NFPA 70E.
Table 130.7(C)(11) was eliminated, as it was rendered redundant by changes made in the 2009 edition to Table 130.7(C)(10). Table 130.7(C)(16) [formerly 130.7(C)(10)] eliminate HRC 2*. All HRC 2 tasks will now require the use of a balaclava under an arc-rated face shield, or the use of an arc-rated hood. There was concern, based on substantiation provided with the original proposal, that the sharp edge of the face shield could create a vacuum as the heat flux flows past it, causing the heat to be pulled in towards the face. This could cause the unprotected face to suffer serious burn injuries, even though it is covered by the face shield.
Annex H has been renamed “Guidance on Selection of Protective Clothing and Other Personal Protective Equipment”
and contains new Table H.3(a), which is an easy method to locate references to PPE contained within NFPA 70E. New Table H.3(b) contains guidance on arc flash protective clothing and PPE when an Incident Energy Analysis is performed. Table H.3(b) shows the required arc flash protective clothing at three levels:
• Less than or equal to 1.2 cal/cm2
• Greater than 1.2 cal/cm2 up to 12 cal/cm2
• Greater than 12 cal/cm2
Previously, the only guidance for arc-rated PPE was in Table 130.9(C)(10), and its use was discouraged by the 70E when an Incident Energy Analysis had been performed. There’s also new Table H.4, titled, “Two-Level Clothing Approach for Use with known Short Circuit Currents and Device Clearing Times.”
There are actually two tables, H.4(a) for low-voltage systems and H.4(b) for high-voltage systems. These tables provide guidance for using 8cal/cm2 and 40cal/cm2 arc-rated clothing and PPE and should add clarity as to when the two-category method would be appropriate to use.
GLOBAL CHANGES TO ENTIRE DOCUMENT The phrase Fine Print Notes (FPN) will not be used in the 2012 edition. They will now be referred to as “Informational Notes”
(IN) in order to conform to the NEC Manual of Style.
Arc-rated will be used instead of FR. It was noted that all arc-rated clothing is FR, while not all FR is arc-arc-rated. This change ensures that arc flash protective clothing and PPE is designed and rated for electrical hazards.
Calories/cm2 is now the preferred rating for arc-rated clothing and PPE. The use of Joules/cm2 is not used in the main body of the standard (one exception – 130.5(A) Arc Flash Boundary). The committee consensus was that all arc-rated clothing and PPE used cal/cm2 and any other term would only add confusion.
Hazard/Risk Analysis has been changed to Hazard Identification and Risk Assessment. This was done to differentiate between the two steps required. Some people confused the hazard with the risk and were not completing both parts as required by the standard.
ARTICLE 100, “DEFINITIONS”
Arc Rating – This definition was expanded upon with two new Informational Notes. One provides the ASTM F1959 definition of ATPV and the other is the ASTM definition of EBT or breakopen threshold.
Boundary, Arc Flash – The word “Protection” was dropped, as it did not add clarity and did not appear in the shock boundaries.
A new Informational Note was added that defined when a person could receive a second-degree burn on bare skin (1.2cal/cm2).
NEW ARTICLE 105, “APPLICATION OF SAFETY-RELATED WORK PRACTICES”
This new article relocated 110.1, “Scope” through 110.4,
“Organization” and used them to make Article 105. The information contained in them is unchanged.
ARTICLE 110, “GENERAL REQUIREMENT FOR ELECTRICAL SAFETY RELATED WORK PRAC-TICES”
This article now begins with “Relationships with Outside Contractors,” since the previous paragraphs were used to make new Article 105.
110.1 now requires that the meeting between a host employer and contractor be documented. This was required in the 2004 edition, was deleted in 2009 and is now back in the 2012 edition.
Place your bets on the 2015 edition.
110.2(C) (formerly 110.6), “Emergency Procedures” has added the requirement for AED training annually. There was some concern about requiring training if the facility does not have AED’s, but the general feeling was that if no AED’s are present, no training is required.
110.2(D), “Employee Training” adds a new requirement that an annual inspection be performed verifying that each employee is complying with the safety-related work practices in NFPA 70E. The wording closely mimics wording in 1910.269. Also, in 110.2 retraining of employees is required every three years. The committee felt that safety training is needed to refresh worker’s awareness and that the three year maximum was not overly burdensome and coincided with the release of the new editions of NFPA 70E. If a company wanted to conduct the training annually there is nothing to restrict that, either.
110.2(E), “Training Documentation” now requires that the content of the training be documented. There was some discussion concerning whether the wording should be “content”
or “description”. “Description” was considered to be too vague.
110.3(E), “Electrical Safety Program Procedures” now includes the wording, “An electrical safety program shall identify the procedures for working within the Limited Approach Boundary and for working within the arc flash boundary before work is started”. Since there are tasks that could create an arc flash hazard Arc-Flash Handbook 37
when there is no shock hazard (racking of breakers and similar tasks) this wording change made sense.
110.3(H), “Electrical Safety Auditing” includes a requirement that field safety audits be conducted to ensure procedures and principles of the electrical safety program are still compliant with the latest standards and regulations. This audit is required no more than every three years. NFPA 70E also requires a field safety audit to be performed to ensure workers are following those standards and regulations.
ARTICLE 120, “ESTABLISHING AN ELECTRI-CALLY SAFE WORK CONDITION”
The provision for Individual Control was eliminated from this article. This allowed a worker to work within a MCC or other such equipment without locking it out. OSHA stated they would find that in violation of their regulations.
ARTICLE 130, “WORK INVOLVING ELECTRICAL HAZARDS”
130.5, “Arc Flash Hazard Analysis,” The erroneous wording of the exception for electrical systems fed by one transformer
<125kVA and <240V in the 2009 edition has been modified to just state that an arc flash hazard analysis may not be needed for three-phase systems <240V and refers the reader to IEEE 1584.
This is now contained in an information note and not an exception in 130.3.
130.5(A), “Arc Flash Boundary” eliminates the 4’
“precalculated” Arc Flash Boundary. There never was a default boundary, but people acted like there was, so the committee felt it best to remove this provision.
130.5(C), “Equipment Labeling” has been reworded to reflect Article 110.16 of the NEC, which is what the committee intended last cycle. It was never the intent to require all electrical equipment to have labels, so this corrects a big misunderstanding. Also, each label must contain the incident energy at working distance or the arc rating of the required PPE or the maximum HRC for that type of equipment. Also required will be the Arc Flash Boundary. A grandfather clause was implemented so companies won’t have to change out their labels every time a new 70E is published.
130.7(A), “Personal and Other Protective Equipment” adds an exception below Informational Note 2 that reads, “It is the collective experience of the Technical Committee on Electrical Safety in the Workplace that normal operation of enclosed electrical equipment, operating at 600 volts or less, that has been properly installed and maintained by qualified persons is not likely to expose the employee to an electrical hazard.” This statement is significant in that many of the users of the 70E believe arc flash PPE may be required to enter equipment rooms that contain normally-operating electrical equipment. That is not the case. It is also the collective opinion of the committee that there is very little risk in performing normal operations of electrical equipment and devices, such as
opening and closing circuit breakers, MCCs or starters. When the committee stated that “interacting with equipment in a manner that could cause an arc flash hazard” constitutes a possible hazard, it was referring to operations such as racking circuit breakers or installing or removing MCC buckets; tasks that involve making and breaking energized electrical connections that are not made for switching.
130.7(C)(9)(a), “Layering” states that clothing that is not arc rated cannot be used to increase the arc rating of a clothing system.
ASTM 1959 does allow this practice, but it only pertains to the manufacture of specific clothing, such as parkas or cold weather gear that has cotton or wool linings. If underlayers are tested as a system, those exact underlayers are the only ones acceptable. The committee did not think there was enough clarity in this to allow it for everyday use.
130.7(C)(10)(b)(2), “Arc Flash Protective Equipment” requires the use of an arc rated hood if the incident energy exceeds 12cal/
cm2.
130.7(C)(11), “Clothing Material Characteristics” clarifies that all materials used in arc-rated clothing is to be arc-rated. Some low-cost manufacturers are using flammable or even melting materials in the construction of arc-rated clothing, which could put the worker at risk.
Article 300, “Safety Requirements Related to Batteries and Battery Rooms.” Deleted all portions of Article 320 dealing with installation requirement. Since NFPA 70E is a work practices standard, the consensus was that installation requirements belonged in the NEC.
Annex D, “Incident Energy and Arc Flash Boundary Calculations.” Informational notes were added to clarify that when the operating time of an OCPD exceeds two seconds how long the person may be exposed must be considered. Two seconds is considered adequate for a person working on the ground, but may not be if a person is working from an elevated platform or bucket truck.
Proposed Annex Q (not the real number) for samples of equipment labels was not accepted by the committee. It was determined that there are too many variations that could be in service and that the annex generally did not add anything to the standard. It was also the feeling of the committee that annexes needed to bring real value to the standard, not just information.
SUMMARY
As a point of clarification, I cannot speak for the 70E committee, nor can I provide official interpretations to the standard. Only the NFPA staff can do that. Any place that I refer to what the committee thought, believed or felt is my personal assessment only.
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There are many more changes that cannot be addressed in this paper due to time limitations. Some may be important to some companies, while others have little consequence to them. It is not the intent of this paper to cover all changes. It is recommended that each reader of this paper purchase a copy of the 2012 NFPA 70E and familiarize themselves with the specifics of that document, as opposed to relying on someone else’s judgment.
James R. White is nationally recognized for technical skills and safety training in the electrical power systems industry.
He is currently the Training Director for Shermco Industries, a NETA Accredited Company. Jim has spent the last twenty years directly involved in technical skills and safety training for electrical power system technicians.
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