NEC and Worker Safety Nov/Dec 16

Posted in: Safety Corner, November/December 2016

The National Electrical Code (NEC) is a document that seeks the practical safeguarding of persons and property from hazards arising from the use of electricity. We all too often forget about how important the NEC is to those working on, in, or around electrical equipment. Some State Code adoption hearings include discussions of delaying adoption of the NEC due to cost of the provisions within these requirements or even the cost of buying new books and conducting training. The most disappointing experiences in my book are the discussions that never happen as states drag their feet and take a casual approach to NEC adoption; yet another way to indirectly achieve a delayed adoption of requirements that are there to save lives and property.

The NEC is more than the benefits of the solutions contained within the document, such as Arc Fault Circuit Interrupters (AFCI), Ground Fault Circuit Interrupters (GFCI), Tamper Resistant Receptacles, and labeling. Often, we overlook examples where the NEC works to ensure safety for those who work in or around electrical equipment. Many of these requirements are not product specific but rather address such relatively simple steps that need to be taken for safety, including but not limited to the layout of a room for emergency egress and ensuring panic hardware on doors for exit. The NEC offers a lot more than reduced property damage and safety for those that reside in a structure; the NEC offers value to those who work on electrical systems.

INSTALLATION CODE VS. WORK PRACTICE

NFPA 70 (NEC) and NFPA 70E, “Standard for Electrical Safety in the Workplace,” differ but complement each other well.

NFPA 70E speaks to electrical safety-related work practices for employee workplaces that are necessary for the practical safeguarding of employees relative to the hazards associated with electrical energy during specific activities, which include but are not limited to installation, inspection, operation, maintenance, and demolition of electrical conductors and equipment. This is not an installation requirement. NFPA 70E is not enforced by the electrical inspection community but is often enforced by the Occupational Safety and Health Administration (OSHA).

The NEC is an installation “Code” that is enforced in the design and installation phases of the structure. The NEC seeks to provide the practical safeguarding of persons and property from hazards arising from the use of electricity through provisions that are considered necessary for safety. As noted earlier, the Code is enforced at the time of installation; a fact very important to grasp.

Lockout/tagout is a good area to explore to illustrate the potential of how these two documents work together. NFPA 70E includes practices around lockout/ tagout with great detail necessary to help the worker ensure equipment is de-energized before work is conducted and assure it remains in that state while work is being conducted. The NEC complements this practice with installation requirements providing for hardware that is ready to receive lockout/tagout equipment, such as locks. The requirements here ensure that the provision on the disconnecting means is present even when the lock is not in place.

The following list are general topics where the NEC works to provide safety for those who work in or around electrical equipment. This list is offered as discussion points with examples to help in the understanding of this important relationship between the NEC and NFPA 70E.

  • Working Space and Guarding
  • Signs, Labels, and Markings
  • Make It Safe
  • Arc Flash and Shock Protection

WORKING SPACE AND GUARDING

Having space to perform work is fundamental when it comes to safety. The NEC recognizes this as part of the requirements found in Article 110, “Requirements for Electrical Installations:”

  • 110.26 “Spaces About Electrical Equipment”
  • 110.32 “Work Space About Equipment”
  • 110.34 “Work Space and Guarding”
  • 110.72 “Cabling Work Space”
  • 110.73 “Equipment Work Space”
  • 110.75 “Access to Manholes”
  • 110.76 “Access to Vaults and Tunnels”

These sections have seen changes over the years and will continue to see changes in the years to come. Section 110.26 includes personnel door requirements. When an emergency occurs and the electrical worker must exit the work area, it is important that he/she is afforded the ability to do so.

A few other sections that arguably fall under this category of working space and guarding can be found in Article 225, “Outside Branch Circuits and Feeders,” where clearances are addressed for overhead conductors and cables and from buildings:

  • 225.18 “Clearance for Overhead Conductors and Cables”
  • 225.19 “Clearances From Buildings for Conductors of Not over 1000 Volts, Nominal”

Addressing working space when equipment is first installed and in the design phases of every project is important for those who come years later to service the electrical equipment.

SIGNS, LABELS, AND MARKINGS

The NEC incorporates many places where signs, labels, and markings are required. In addition to UL standards that products must adhere to, the NEC works to ensure consistency in this area. Section 110.21(B), “Field-Applied Hazard Markings,” references ANSI Z535.4- 2011, “Product Safety Signs and Labels,” which provides guidelines for suitable font sizes, words, colors, symbols, and location requirements for labels.

The NEC includes requirements for arc flash hazard warning labels on equipment as part of Section 110.16, “Arc-Flash Hazard Warning;” cable tray labels in 230.44, “Cable Trays;” and the cables themselves in 210.5(C), “Identification of Ungrounded Conductors.” These are merely examples as there are many more. Hazards that you may not be aware of are brought to light as demonstrated in Section 404.6, “Position and Connection of Switches,” raising awareness that load side terminals may be energized is brought forth through the requirement for a label with the following language, “WARNING — LOAD SIDE TERMINALS MAY BE ENERGIZED BY BACKFEED.”

MAKE IT SAFE

As with any electrical project, ensuring a safe work condition is essential; working de-energized should be priority one. The NEC includes important provisions to help you increase safety on the job site through requirements for disconnecting means to be made available when needed as well as help ensure all conductors are de-energized when the circuit is turned off. The NEC caps off the installation with provisions around illumination.

Notable sections include 110.25, where the NEC puts in place the provisions to affix the lockout/tagout tools highlighted by NFPA 70E. This section requires that where a disconnecting means is required, it must be lockable in the open position. An example of a disconnecting mean provisions is found in Article 430, where a disconnecting means must be provided for motors as part of Section 430.102(B).

Section 110.26, where spaces about electrical equipment are discussed, or more specifically 110.26(D), “Illumination,” requires that illumination be provided for all working spaces around service equipment, switchboards, switchgear, panelboards, or motor control centers installed indoors. This section also requires that this lighting is NOT controlled by automatic means only. You must be able to ensure the light does not automatically turn off just when you need it the most. Another area of the code that expands on this requirement includes battery locations. Section 480.9(G), “Illumination,” includes similar provisions to that in 110.26 to ensure working spaces where battery systems are located are illuminated.

ARC FLASH AND SHOCK PROTECTION

Incident energy and electric currents can kill. The NEC includes provisions to help mitigate the effects of both for the electrical worker. Section 240.87 provides methods to reduce the level of incident energy.

Shock protection has been a part of the NEC for quite some time in the form of GFCIs. One example is found in Article 590, where shock protection provisions are included as part of Section 590.6, “Ground-Fault Protection for Personnel.”

CLOSING REMARKS

Electrical safety is more than just applying a product or sitting through a training class; it’s a regimen of training and procedures implemented in combination with technology that saves lives. The NEC and NFPA 70E work together to help you in your quest for safety. Be an advocate of safety by at least doing the bare minimum – share your knowledge with those around you. Spread your knowledge; it just may save a life or keep someone out of the hospital.

As always, keep safety at the top of your list and ensure you and those around you live to see another day. If you have any tips or ideas you would like to share, please feel free to send them to me at thomasadomitrovich@eaton.com. I look forward to your input to these articles and guidance for future articles.

Thomas Domitrovich, P.E., is a National Application Engineer with IEC Platinum Partner Eaton Corporation in Pittsburgh, PA. He has more than 20 years of experience as an Electrical Engineer and is a LEED Accredited Professional. Domitrovich is active in various trade organizations on various levels with IEC, International Association of Electrical Inspectors, Institute of Electrical and Electronic Engineers (IEEE), National Electrical Manufacturer’s Association (NEMA), and the National Fire Protection Association (NFPA). He is involved with and chairs various committees for NEMA and IEEE and is an alternate member on NFPA 73. He is very active in the state-by-state adoption process of NFPA 70, working closely with review committees and other key organizations.