- OIL & GAS
- New PPE Category tables
- Eliminating HRC 0
- Eliminating the Prohibited Approach Boundary
There are many more changes than can be covered in this article. Only a few of the more significant changes are covered due to space constraints, although I will be revising my pocket guide, “Significant Changes to NFPA 70E – 2015 Edition” published by American Technical Publishers (go2ATP.com). This article does not attempt to provide a formal interpretation of NFPA 70E. To receive a formal interpretation, please contact NFPA directly.
In order to clarify the question of wearing arc-rated PPE and clothing to operate a <600V device, the technical committee stated in the 2012 edition of NFPA 70E in Section 130.(7)(a) IN No. 2, “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 Informational Note explains that normal operation of equipment that has been properly installed and maintained is not likely to pose an increased arc flash risk. The key to this statement is “not likely”. “Not likely” does not mean “never”, nor does it imply that PPE is not required under all circumstances. Qualified persons will still have to assess the risks involved in performing any task and dress out accordingly. This is true whether the PPE Category Tables are used or Arc Flash Hazard Warning Labels. Turn the autopilot to the OFF position.
That being said, there was still confusion in the industry. In an attempt to bring more clarity to the committee’s intent, 130.2.(A)(4) was added, “Normaloperation of electric equipment is permitted when all of the following conditions are satisfied:
o The equipment is properly installed;
o The equipment is properly maintained;
o All equipment doors are closed and secured;
o All equipment covers are in place and secured; and
o There is no evidence of impending failure.”
The inclusion of 130.2(A)(4) should make clear that it is not the intent of the Technical Committee to force the wearing of arc-rated clothing and PPE to operate an electrical device in the manner specified by the manufacturer. That being said, the Technical Committee would encourage workers to wear such PPE and clothing whenever that worker believes it might be needed or is more comfortable wearing such equipment. As an example, if I were about to operate a 480 V circuit breaker with a continuous current rating above ~1,000A I would dress out on HRC 2 PPE and arc-rated clothing. It should also be noted that “normal operation” means to operate the equipment in the manner specified by the manufacturer. If the manufacturer states that a push button must be used to operate the equipment, operation by any other means would be outside the scope of this statement and it would not apply.
Section 130.2(A)(4) includes an Informational Note that explains what is meant by “properly installed” and “properly maintained”. “Informational Note: The phrase "properly installed" means that the equipment is installed in accordance with applicable industry codes and standards and the manufacturer's recommendations. The phrase "properly maintained" means that the equipment has been maintained in accordance with the manufacturer's recommendations and applicable industry codes and standards. The phrase "evidence of impending failure" means that there is evidence such as arcing, overheating, loose or bound equipment parts, visible damage, or deterioration.” This is the first time these terms have been defined in NFPA 70E and provides a basis for determining equipment condition.
The Second Draft of this section eliminates the Prohibited Approach Boundary for the shock hazard. This is an attempt to clarify the 70E and make it easier for field workers to use. The Limited Approach and Restricted Approach Boundaries both are triggers for certain actions. The Limited Approach Boundary is the closest an unqualified person can approach exposed energized conductors or circuit parts and the Restricted Approach Boundary is the point at which a qualified person must wear insulating rubber gloves or take other action to protect themselves from the shock hazard. The Prohibited Approach Boundary contained no such trigger and people in general seemed to be confused as to its purpose.
This section requires that arc flash hazard analysis (now called risk assessments) be updated when a major renovation or modification to the electrical system occurs. Actually, anything that could cause a change in the available short circuit current or operating time of OCPDs requires an update. There is also a requirement for a periodic review (no more than five years) to determine if any changes have occurred that could change the assessment.
Changes might include, but would not be limited to an increase in transformer capacity, a transformer with lower impedance, installing larger power cable in a circuit or changing OCPD settings.
The requirements for labeling of electrical equipment have been a point of confusion for the last cycle or two. Part of the reason was the 2009 edition of NFPA 70E only stated that electrical equipment had to be labeled. This led some to believe that anything electrical had to be labeled. The wording in the 2015 edition should clarify exactly what the intent is. It states, “Electrical equipment such as switchboards, panelboards, industrial control panels, meter socket enclosures, and motor control centers that are in other than dwelling units and that are likely to require examination, adjustment, servicing, or maintenance while energized shall be field-marked with a label containing all the following information:
(1) Nominal system voltage
(2) Arc flash boundary
(3) At least one of the following:
a. Available incident energy and the corresponding working distance
b. Minimum arc rating of clothing
c. Site—specific level of PPE
d. PPE category in 130.7(C)(15)(b) or130.7(C)(15)(d) for the equipment.”
Only equipment that may require inspections, adjustment, servicing or maintenance while energized are required to have the field marking (label) in place. If the equipment does not require inspection, adjustment, servicing or maintenance while energized, it does not require the label.
Section 130.5(B) also states, “Exception: Labels applied prior to September 30, 2011, are acceptable if they contain the available incident energy or required level of PPE.”
“The method of calculating and the data to support the information for the label shall be documented.
Where the review of the arc flash hazard risk assessment identifies a change that renders the label inaccurate, the label shall be updated.”
“The owner of the electrical equipment shall be responsible for the documentation, installation, and maintenance of the field-marked label.”
The underlined portions of the above two paragraphs show the added requirements for 2015. If the label becomes inaccurate for any reason, it must be updated to reflect the current requirements for that piece of equipment. It also states that the equipment owner is the person responsible for the required labels. The owner does not have to personally install or maintain the labels, but he is responsible to see that it is done.
Section 130.6(H) states, “Clear Spaces. Working space in front of electrical equipment required by other codes and standards shall not be used for storage.” This section is to meet requirements of various fire codes, which forbid storing anything, even temporarily, in the working space of electrical equipment. That working space changes with the nominal voltage of the equipment and can be found in the National Electrical Code. If there is a problem where the equipment must be shut down or operated, materials storage could interfere.
New Arc Flash PPE Tables 130.7(C)(15)(a) and (b)
The NFPA 70E technical committee has agreed to a new format for choosing arc-rated clothing and PPE. Table 130.7(C)(15)(a) will be split into two tables. The first table is used to determine if an arc flash hazard exists. One of the complaints about the current table method is that tasks that do not pose an arc flash hazard are listed in the table, such as operating a panelboard meter. If no arc flash hazard exists, why have that task in the table? The answer is that in using the old table method, all tasks common to that equipment were listed to ensure workers knew that some tasks were not an arc flash hazard. It is somewhat clumsy and confusing. The HRC for a category of equipment could be down-rated by 1, 2 or even 3 numbers, based on perceived risk. Under the new table method, no such reduction is used. If there is an arc flash hazard, you must wear all the required PPE and clothing.
Figure 1shows a portion of the proposed table for the 2015 NFPA 70E. No arc flash hazard means nothing further is required. If there is an arc flash hazard, then you would move to the second (new) table and choose the arc flash category of the recommended clothing and PPE. This is based on the same limits as the current table and the categories remain the same. The difference is that there is no risk factored in. Risk is still a factor, but now the level of risk is determined by conducting a risk assessment for that specific task on that specific piece of equipment, but only for tasks that pose an arc flash hazard.
Note that in this new table there is no perceived arc flash hazard if the equipment is properly installed, properly maintained and there is no evidence of impending failure on some of the listed tasks. This is critical, as these factors have to be part of the risk assessment required by NFPA 70E. If a worker is troubleshooting electrical equipment, it is no longer normally operating; it is in distress and arc flash protective equipment must be worn to operate it or perform any other task on or with it. If an arc flash hazard is present, the second new table is used to determine arc-rated clothing and PPE. Figure 2 shows a portion of the new proposed table.
HRC 0 was eliminated, as the committee felt that this table should only show requirements where arc-rated clothing was required. HRC 0 would mean the worker was outside the arc flash boundary and did not need arc-rated PPE or clothing. Section 130.7(C)(11) states, “Clothing consisting of fabrics, zipper tapes, and findings made from flammable synthetic materials that melt at temperatures below 315°C (600°F), such as acetate, acrylic, nylon, polyester, polyethylene, polypropylene, and spandex, either alone or in blends, shall not be used.” This section as well as section 130.7(C)(12) prohibit the wearing of meltable fabrics, but was not clear that such fabrics cannot be worn for any electrically-related task. One of the concerns voiced during balloting of the tables is the concern that workers would wear permanent press of other melting-type clothing because HRC 0 was removed. The Correlating Committee (the oversight committee for the 70E) formed a task group to make recommendations on this concern. The result is a proposed TIA (Tentative Interim Amendment) will be circulated that adds a statement that noting that clothing shall meet the non-melting requirements of 130.7(C)11 and 130.7(C)12 when this table indicates arc flash PPE is not required
The category of the arc-rated clothing and PPE is still determined by the type of equipment and has the same limits, but is no longer task-based. The arc flash boundaries (AFB) are rounded up to the nearest foot (except for PPE Category 1) and working distances are the same as in the current table. Risk is removed as a determining factor in the table, although risk must be determined by the user. PPE Category 1 was stated in inches, as rounding up caused a conflict with the requirement that “all parts of the body inside the Arc Flash Boundary (AFB) must be protected”. At 24” the back of the head would probably be within the AFB and the worker would have to wear an arc-rated balaclava. This is not the intent of the committee and additional wording was added so that the trigger for an arc-rated balaclava would be above 4 cal/cm2. That being said, there is a proposed TIA on this subject that is being circulated for voting. That proposed TIA has not yet been sent to the committee members, so I don’t know what its exact content is, but the Correlating Committee believes there is a conflict that must be resolved.
Chapter 2 of NFPA 70E
Chapter 2 is like the greatest book no one bothers to read. It is one of the foundations of NFPA 70E, though and if the requirements given in Chapter 2 are not met, then Chapter 1 really cannot be not valid. If the requirements of Chapter 2 are not met, then that expensive arc flash hazard study that cost so much is of very limited value. If the electrical power system equipment is not maintained, there is no method to determine what protective clothing or procedures are to be followed. Another concern raised about the new tables was that the average technician would not be able to determine the condition of maintenance for equipment. This was a problem voiced about the current tables, also, but became more of an issue during balloting for the Second Draft.
This concern was addressed by the addition of one of the new Informational Notes in Section 200.1. It provides a method to determine if electrical equipment has been properly maintained. It’s a labeling method that would alert a worker who may not be familiar with the equipment as to its current maintenance status. 205.4 IN states, “Informational Note: Common industry practice is to apply local indication as to the date and overall condition of specific devices that have been tested and maintained in the field. The local indication provides the employee immediate indication of last maintenance date and if the tested device or system was found acceptable on the date of test. This local information can assist the employee in the assessment of overall electrical equipment maintenance status.” This section refers to NFPA 70B, Recommended Practice for Electrical Equipment Maintenance, which has Service Classification Labels to identify equipment as “Nonserviceable,” “Limited Service” and “Serviceable.”
Section 205.3, General Maintenance Requirements has been modified to state, “Electrical equipment shall be maintained in accordance with manufacturers’ instructions or industry consensus standards to reduce the risk of failure and the subsequent exposure of employees to electrical hazards associated with failure. The equipment owner shall be responsible for maintenance of the electrical equipment and documentation.” The underlined portion of the text indicates where the change is proposed. Note that the equipment owner is also responsible for maintaining the equipment in a safe condition.
There are three industry consensus standards that cover maintenance of electrical power systems and devices; NFPA 70B, Recommended Practice for Electrical Equipment Maintenance, and ANSI/NETA MTS-2011,Standard for Maintenance Testing Specifications for Electrical Power Distribution Equipment and Systems, and IEEE Std 3007.2
IEEE Recommended Practice for the Maintenance of Industrial and Commercial Power Systems. Each of these have differing types of information and each are valuable resources for companies to evaluate and improve their maintenance programs.
Section 205.14 Flexible Cords and Cables has wording that reflects the Technical Committees concern that extension cords and other electrical cables are being repaired or modified by unqualified persons. It states, “(3) Repair and Replacement. Cords and cord caps for portable electrical equipment shall be repaired and replaced by qualified personnel and checked for proper polarity, grounding and continuity prior to returning to service.”
NFPA 70E is far from the perfect document everyone would like to have. It is a work in progress, with each edition refining and improving on the last. The Technical Committee wants to have a standard that is usable, easy to interpret and will provide a means to guide technicians and electricians to establishing a safe work environment. There is some disagreement within the committee about how the 70E should fulfill that role. Should it represent “best safe work practices” or should it provide “minimum acceptable guidelines”? I fall into the “minimum acceptable guidelines” group. A qualified person should be able to assess the hazards and risks involved in performing the task at hand and also be able to assess equipment condition. If they are unable to perform those requirements, they should not be considered a qualified person and require additional training. I don’t believe the 70E should attempt to provide “best safety work practices”, because it is not practical for the committee to properly evaluate and establish specific when there are so many variables. I believe the committee members who believe the 70E should provide best safe work practices have workers best interests in mind, but trying to do so could cause the opposite effect. I don’t believe we want a standard that people use as the only means to determine safe work practices, regardless of the actual site conditions. Qualified persons must be able to perform their personal evaluations based on site and equipment conditions at the time of the task being performed. A standard cannot address that and should not attempt to. That’s my thought, anyways.