Some people may not consider Article 90 of NFPA 70®, National Electrical Code® (NEC®), to be a backbone of electrical inspector knowledge. But a familiarity with Article 90 is crucial for electrical inspectors. The sections found within Article 90 provide a comprehensive overview of when the NEC applies and when it doesn’t, how the code is arranged, and how enforcement works—all information that is valuable to any electrical inspector. In this blog, we’ll go over some of the information in Article 90 that is important for electrical inspectors to know. What does the NEC cover? Section 90.2(C) lists areas covered by the NEC, and they are: 1.     Public and private premises, including buildings, structures, mobile homes, recreational vehicles, and floating buildings 2.     Yards, lots, parking lots, carnivals, and industrial substations 3.     Installation of conductors and equipment connecting to the supply of electricity 4.     Installations used by electric utility, such as office buildings, warehouses, garages, machine shops, and recreational buildings, that are not an integral part of a generating plant, substation, or control center 5.     Installations supplying shore power to ships and watercraft in marinas and boatyards, including monitoring of leakage current 6.     Installations used to export power from vehicles to premises wiring or for bidirectional current flow As you can see, the NEC addresses installations and methods of accomplishing those installations in its areas of coverage. The fifth item was added in the 2020 edition of the NEC to address installations of shore power and associated receptacles in marinas and boatyards, which may help lower the risk of exposure to electric shock drowning (ESD) through specific changes made in Article 555. The sixth item was also added in the 2020 NEC to deal with new technology around electric vehicles (EVs) and their ability to provide power to premises electrical systems through the EV charging equipment. The changes are reflected in Article 625. What doesn’t the NEC cover? Just as important as knowing what the NEC covers is knowing what it doesn’t. Section 90.2(D) lists the areas that are not under the purview of the NEC, which helps electrical inspectors navigate the out-of-bounds line. This is not to say there are no electrical inspections happening in those areas—just that if there are any, they are likely done using a code or standard other than the NEC for determining compliance. For example, utility-owned service or transmission line installations are covered by the National Electrical Safety Code (NESC) and not the NEC. How is the NEC arranged? The NEC arrangement is outlined in Section 90.3. The NEC is organized so that the requirements found in Chapters 1 through 4 apply generally to all electrical installations referenced in the code, except those referenced in Chapter 8, where the code language must have specific references to the first four chapters. This arrangement helps consolidate general requirements into a few chapters so that they’re not repeated elsewhere in the NEC, which makes it easier for electrical inspectors and installers to locate. Enforcement Information for electrical inspectors around enforcement, interpretations, specific requirements, and what to do with new products, constructions, or materials is found in Section 90.4. According to 90.4(A), the NEC is suitable for mandatory application by governmental bodies that have legal jurisdiction of electrical installations. These bodies are usually state, county, or city governments that incorporate the NEC by reference into their rules or laws. In most instances, electrical inspectors must be working under the authority of an enforcing agency or for an authority having jurisdiction (AHJ) to have any enforcement powers over permitted electrical installations within those jurisdictional boundaries. AHJs have the responsibility for making interpretations of the rules and for deciding on the approval or rejection of equipment or materials used in electrical installations. They may also grant special permission in certain circumstances as they deem necessary. There are two types of rules in the NEC: mandatory and permissive. They are expressed very differently. Mandatory rules are the shall or shall not rules. For example, a mandatory rule would be “the electrical connection of conductors to terminal parts shall ensure a mechanically secure connection without damaging the conductors,” whereas a permissive rule would be “reconditioned equipment shall be permitted except where prohibited elsewhere in the NEC.” As a former AHJ, I frequently would tell electrical inspectors that the code isn’t what you THINK it says; it is what it SAYS it is, so go read the code section before writing a violation or approving an installation. Understanding the difference between mandatory and permissive rules can help the enforcer-installer relationship by having a more accurate inspection. Where to go for more information Electrical inspectors, you are not alone in what you do. NFPA® has an Electrical Inspection Section membership just for you, where you can network with other electrical inspector members. Inspectors can share ideas, talk code, and collaborate on interpretations of the code through NFPA XchangeTM. Having these tools will help create a more consistent enforcement of the NEC.

NFPA 70E®, Standard for Electrical Safety in the Workplace® Section 110.5(M)(1) requires auditing of your electrical safety program (ESP) to determine if the ESP continues to comply with current NFPA 70E requirements. Section 110.5(F) requires that the ESP identify the controls by which it is measured and monitored. Electrically safety in the workplace will stagnate without this step where improvements for safety are implemented. Controls are the electrical safety metrics for determining if an ESP is effective and efficient. To evaluate a system, you need to know where you started and how far you have come. Controls must be both measurable and actionable. Metrics are measurable points to determine performance. They are used to determine if improvements to the safety program are required and, if so, what needs to be changed. NFPA 70E requires controls but it is the documented ESP that details what they are and how they are used. It is necessary to identify who is responsible for analyzing the data and incorporating necessary changes. There are two common metrics used to determine the effectiveness of something: lagging and leading. Lagging metrics provide a reactive view of an ESP. Lagging metrics might include the time lost to injuries, the money spent on worker compensation, or the amount of training an employee has received. Under this metric, an injury occurs, and the ESP is changed to address it. A shock is reported, and a change is made. Leading metrics identify and correct contributing factors before an incident occurs. Leading metrics might include the number of hazards identified and eliminated, the reduction in the number of authorized energized work permits, or the number of work procedures altered for de-energized work. Under this metric, a decrease in electricity injuries might be evident after hazard elimination was instituted or after every employee had been trained on the proper use of with extension cords. A combination of these metrics can enhance a safe work program. The next step is determining where further improvements could be made to the system. The ESP must detail what controls are implemented, how they are evaluated, how data is collected, how changes are incorporated, and who is responsible for maintaining the control system. The process should address how much change may occur at one time. Incremental steps are easier to monitor than whole scale changes. If the system heads in the wrong direction it is easier to correct its course, then try something else. Make sure that your ESP has appropriate controls to keep electrical safety progressing in your workplace. This concludes the 12-part series on an ESP. NFPA 70E requirements cannot be used as appropriate procedures or for training for any specific task. A well-developed ESP is critical to achieving electrical safety in the workplace as well as for complying with NFPA 70E and OSHA regulations. Without it there are no policies and procedures available for employee training and there can be no qualified persons without proper training. Review your ESP to make sure all requirements and safety issues are properly addressed.

January 2023 was a significant month in the evolution of NFPA 70B as it transitioned from the Recommended Practice for Electrical Equipment Maintenance to the Standard for Electrical Equipment Maintenance. Issued by the NFPA® Standards Council on December 27, 2022, the 2023 edition of NFPA 70B, Standard for Electrical Equipment Maintenance, became effective on January 16, 2023, when it was approved as an American National Standard by the American National Standards Institute (ANSI).   It has been 50 years since the first version of NFPA 70B was issued in 1973 as a recommended practice, which provided recommendations on what should be done. Now, the move to a standard provides more enforceability for what must be done when it comes to electrical equipment maintenance. That is a win-win for both the reliability of electrical equipment and the overall safety of the electrical systems and those individuals tasked with working on them.     Why is electrical equipment maintenance important?   Unexpected shutdowns can be detrimental to companies, yet they happen every day due to equipment failure. Just as vehicles require regular upkeep to remain reliable as usage and aging persist, maintenance is also vital for electrical systems to stay dependable when they are needed.   Even more critical than the safety of the electrical system itself is the safety of those responsible for working on those systems. Equipment can be replaced; lives cannot. In part, the defined purpose of NFPA 70B is “to provide for the practical safeguarding of persons, property, and processes from the risks associated with failure, breakdown, or malfunction” of electrical equipment. An additional part of the scope also serves to provide “a means to establish a condition of maintenance of electrical equipment and systems for safety and reliability.”   A key term within the defined purpose of NFPA 70B is condition of maintenance. If you work regularly with electrical codes and standards, that term may be familiar to you. According to a quick search using NFPA LiNK®, the term condition of maintenance is used 59 times in the 2023 edition of NFPA 70®, National Electrical Code® (NEC®), and six times in the 2021 edition of NFPA 70E®, Standard for Electrical Safety in the Workplace®.   While the term is mentioned fewer times in NFPA 70E, establishing a condition of maintenance is paramount in being able to accomplish the requirements outlined within the pages of the document to help keep workers safe. As an example, NFPA 70E, Section 110.5(A), requires employers to implement and document an electrical safety program (ESP) that directs activity appropriate to the risk associated with electrical hazards. Additionally, the ESP is required to include elements that consider the condition of maintenance of electrical equipment and systems.   Without question, electrical equipment that has not been maintained properly or is not functioning properly poses a significant additional risk to those who are working on that equipment and its associated systems. NFPA 70E states that we must address and consider conditions of maintenance for applications—for example, estimating the likelihood of severity in both shock risk and arc flash risk assessments.   NFPA 70B is the standard that can now be both utilized and enforced, to ensure that the proper conditions of maintenance have been established.     Along with NFPA 70B and NFPA 70E, it is also important to keep in mind that the NEC is an important part of this conversation. A code-compliant installation that has been designed, installed, and inspected in accordance with NEC requirements is foundational in being able to incorporate the other standards. Once installation has taken place, NFPA 70B can assist in the maintenance aspect, while NFPA 70E can provide the work practices necessary to keep employees safe, while also meeting Occupational Safety and Health Administration (OSHA) requirements. The NEC, NFPA 70B, and NFPA 70E all become critical components, one just as important as the others, in order to achieve the electrical cycle of safety.   While it may take some time for jurisdictions to determine how to best utilize and enforce NFPA 70B, the NFPA Standards Council’s recent decision to make the document a standard opens the door to that possibility. Because proper maintenance is critical to achieving reliability and safety of electrical equipment and systems—and, more importantly, the safety of workers that interact with them—it is well worth the effort to enforce NFPA 70B as a standard, making it another tool to assist in achieving overall electrical safety in the world.   Find out more information and gain free access to the standard by visiting the NFPA 70B  document information page.

Mobile energy storage systems are being deployed in jurisdictions around the world, and—as demonstrated by a 2023 New Year’s Day mobile energy storage system fire—accidents can happen. We want to make sure communities are prepared for when these systems are deployed in their backyard. This blog will outline key considerations for mobile energy storage systems. To see the full requirements, check out the latest edition of NFPA 855, Standard for the Installation of Stationary Energy Storage Systems. What is a mobile energy storage system?   An energy storage system (ESS) is a group of devices assembled together that is capable of storing energy in order to supply electrical energy at a later time. A mobile energy storage system is one of these systems that is capable of being moved and typically utilized as a temporary source of electrical power. In practice, this is often a battery storage array about the size of a semi-trailer. Mobile energy storage systems can be deployed to provide backup power for emergencies or to supplement electric vehicle charging stations during high demand, or used for any other application where electrical power is needed. While there are various types of ESS and many battery technologies, this blog will focus on the most prevalent type—lithium-ion battery energy storage systems. Many of these requirements apply to any type of mobile energy storage system; see NFPA 855 requirements for details on other technologies. When does NFPA 855 apply to mobile energy storage systems? The scope of NFPA 855 states that it applies to “mobile and portable energy storage systems installed in a stationary situation.” It also goes on to mention that the storage of lithium-ion batteries is included in the scope of the document. The application section then limits the application of the standard to certain-sized mobile energy storage systems. For all types of lithium-ion batteries, the threshold is 20 kWh (72 MJ) before the requirements of NFPA 855 apply. For batteries in one- and two-family dwellings and townhouse units, that threshold is reduced to 1 kWh (3.6 MJ). For more information on residential ESS requirements, check out our previous blog on that topic. When looking at how a mobile energy storage system works, we break its use down into three phases: the charging and storage phase, the in-transit phase, and the deployed stage. This is how I’ll break down the requirements as well. Charging and storage When charging and storing a mobile energy storage system, the requirements are relatively straightforward. The system should be treated as a stationary system as far as the requirements of NFPA 855 go. These requirements will vary based on whether the system is being stored indoors, outdoors, on a rooftop, or in a parking garage. In-transit While a mobile energy storage system is in transit from its normal charging and storage location to its deployment location, it typically travels on roads that are governed by the governmental transportation authority (in the US, that would the Department of Transportation). However, when the mobile energy storage system needs to be parked for more than an hour, it needs to be parked more than 100 ft (30.5 m) away from any occupied building, unless the authority having jurisdiction (AHJ) approves an alternative in advance.  Deployment documents Before a mobile energy storage system is deployed, it needs to be approved by the AHJ, and a permit must be obtained for the specific use case. The permit application must include the following items: Mobile Energy Storage System Permit Application Checklist o Information for the mobile energy storage system equipment and protection measures in the construction documents o Location and layout diagram of the area in which the mobile energy storage system is to be deployed, including a scale diagram of all nearby exposures o Location and content of signage o Description of fencing to be provided around the energy storage system and locking methods o Details on fire protection systems o The intended duration of operation, including connection and disconnection times and dates o Description of the temporary wiring, including connection methods, conductor type and size, and circuit overcurrent protection to be provided o Description how fire suppression system supply connections (water or another extinguishing agent) o Maintenance, service, and emergency response contact information. Deployed There are restrictions on where mobile energy storage systems can be deployed. For example, they are not allowed to be deployed indoors, in covered parking garages, on rooftops, below grade, or under building overhangs. There is also a restriction on how long mobile energy storage systems can be deployed before they need to be treated as a permanent energy storage system installation, and that threshold is 30 days. Additional limitations for where a mobile energy storage system can be deployed include a 10 ft (3 m) limitation on how close it can be to various exposures and a 50 ft (15.3 m) limitation on how close it can be to specific structures with an occupant load of 30 or greater. See NFPA 855 or the image above for more details on the exposures and occupancies. An energy storage system contains a large amount of energy stored in a small space, which may make it the target for those who look to cause harm. For this reason, a deployed mobile energy storage system is required to be provided with a fence with a locked gate that keeps the public at least 5 ft (1.5 m) away from the ESS. Conclusion There are many applications where mobile energy storage systems can play a pivotal role in helping deliver electricity to where it is needed. While this technology has great practical applications and even more potential, it’s important to recognize that it also brings unique hazards. Adherence to the requirements of NFPA 855 can help keep our communities safe while embracing current technology. Here are some additional NFPA® resources related to ESS safety: -       Energy storage system landing page -       Energy Storage and Solar Systems Safety Online Training -       Energy Storage Systems Safety Fact Sheet

If chickens don’t fly, then how can egg prices continue to soar? Poor attempts at dad jokes aside, record-high egg prices are something we are all facing at the moment and, frankly, don’t find all that funny. According to data from the US Bureau of Labor Statistics, the average price of eggs more than doubled between January 2022 and December 2022, from $1.93 per dozen to $4.25 per dozen. Since January 2021, when egg prices were on average $1.47 per dozen, the price has nearly tripled. While many individuals had previously chosen to raise chickens at their residence for access to fresh eggs, elevated egg prices now have many contemplating doing the same to save money.   RELATED STORY  After a large chicken farm fire in Connecticut, some people are questioning whether something suspicious is going on. The truth is there’s nothing unusual about fires at livestock storage and production facilities. Read more.   One of the most critical components in raising chickens is having a structure to provide nesting areas for egg laying and safe shelter from predators such hawks, coyotes, and foxes. Creating structures, such as chicken coops, can often become do-it-yourself (DIY) projects for homeowners. Communication between the local jurisdiction and homeowners about the safe building, and upkeep, of residential DIY chicken coops is key. Below you will find some information on some potential dangers and guidelines to help mitigate the associated risk, as well as a simple tip sheet to that can be shared with others in your community.   The danger of DIY   While it is always recommended that people reach out to the local building department to determine whether or not a chicken coop would need any permits or inspections, the reality is that in many cases these structures are not inspected. In some areas, jurisdictions have excluded permitting and inspections for structures used in private agricultural applications like chicken coops. In other cases, the homeowner may simply not be aware of the potential risks they are exposing themselves to by doing the work themselves and not having adequate inspections performed.   Bad information can also increase risk. An internet search for “raising chickens” led me to a popular DIY site that many homeowners are familiar with. In reviewing the step-by-step process that was provided for raising chickens, it did not take very long before I became astounded at some of the recommendations.   As part of the step for setting up a brooder, which is a heated nesting place for chicks, it was recommended to get a cardboard or plastic box, place it in your house, put pine shavings in the bottom of the box, and place a heat lamp on the side of the box. So, a homeowner is being advised to take a flammable box, add additional flammable material (pine shavings), attach a heat source to the flammable box, and place that box within their home. The immense risk associated with this advice may be caught easily by a cautious homeowner, but there are likely many individuals who would just follow the step-by-step instructions, putting themselves in unnecessary danger.   " A homeowner is being advised to take a flammable box, add additional flammable material, attach a heat source to the flammable box, and place that box within their home.     Other risks and what the codes say   From a codes and standards perspective, it is difficult to find requirements that are specific to residential chicken coops. Paragraph 17.1.3.3 of the 2022 edition of NFPA 150, Fire and Life Safety in Animal Housing Facilities Code, defines facilities where agricultural animals are housed in private, residential-type animal housing as Category 7 Class B. Yet when we look at 17.1.1.3, it states that Category 7 Class B facilities are exempt from the requirements of NFPA 150. Considering this information, we cannot look to NFPA 150 for requirements when building a residential chicken coop.   When we begin to analyze the genuine danger that can be present within chicken coops, two of the most prevalent arise when dealing with sources of electricity and heat. Let’s focus on electricity for the moment. To start, electrical work should always be performed by a qualified electrician who is versed in the requirements of NFPA 70®, National Electrical Code® (NEC®).   Electrical receptacle needs for the chicken coops should be well thought out to avoid the need to use extension cords. Because of the outdoor location and moisture associated with that environment, which can even become an issue inside of the chicken coop, all receptacles should be provided with ground-fault circuit interrupter (GFCI) protection. Poultry dust buildup is a concern for the electrical system as well. To help avoid contact with ignition sources such as the internal components of receptacles and switches, dust-resistant boxes and covers should be utilized as well as implementing light fixtures with fully enclosed lamps. Any dust buildup on electrical components should be cleaned regularly. All electrical equipment that is used in chicken coops, such as heat lamps and electrically heated poultry waterers, should be listed by a qualified testing laboratory. For safety reasons, listed electrical equipment should only be used based on its listing instructions, and non-listed and makeshift equipment should be avoided. Heated waterers, heat lamps, and space heaters might be utilized in chicken coops to keep water from freezing during the winter months, as well as within brooders to keep chicks warm. Because chicks cannot regulate their body temperature for the first few weeks of life, supplemental heat is necessary. Temperatures as high as 95 degrees Fahrenheit are needed during their first week of life, then the temperature gradually descends to about 65 degrees over the next several weeks until chicks can regulate their own body temperature. Hay, bedding, and other combustible materials close to heat sources can become a significant fire hazard within chicken coops and brooders.   NFPA® offers a helpful “Backyard Chicken Coop Safety” tip sheet for the general public that touches on many of these topics and more. Please feel free to share with your community through social media and outreach events.   Chicken coop fires are very real, as evidenced by a recent fire at Hillandale Farms in Bozrah, Connecticut, which killed over 100,000 chickens. While a backyard residential chicken coop may not be anywhere near the scale of this facility, the same potential for electrical and fire hazards still exists. Ensuring that all involved are aware of those risks, and know how to mitigate them, is a critical component to maintaining the safety of people, the flock, the chicken coop, and any surrounding buildings on the property. Don’t put any, let alone all, of the eggs in an unsafe basket.

This is the last in a three-part series on electrical rooms. Read Part 1 here and Part 2 here. Working space about electrical equipment is covered in Article 110 of the NEC.  Up to this point, we have discussed electrical rooms and how the National Electrical Code® (NEC®)—specifically, 110.26—helps ensure there is enough space, especially working space, in those rooms or areas. In Part 2, we observed that changing the voltage alters some of the clearance requirements for the equipment in electrical rooms (see 110.32 and 110.34 of the NEC). Now, we will look at an electrical enclosure, vault, or tunnel that is being used as a method for guarding electrical equipment and see how it affects clearances for working space about electrical equipment. What is an electrical enclosure?  First, let’s look in Article 100 to see if there is a definition for a vault or tunnel. We find there isn’t one, but we do find a definition for enclosure. Enclosure is defined as “the case, housing of an apparatus, or the fence or walls surrounding an installation to prevent personnel from accidentally contacting energized parts, or to protect the equipment from physical damage.” So, does this definition cover an electrical room or vault? I think it could, because the vaults are areas typically surrounded by walls and frequently some form of lockable entrance. Does a vault or enclosure still require working space for electrical equipment? Yes, Parts II and III of Article 110 cover these requirements. For voltages of 50 to 1000 volts, nominal, 110.27(A)(1) would address the use of a room, vault, or similar enclosure that is accessible only to qualified persons, as a means of protection against accidental contact with live parts. For the over 1000 volts, nominal, installations, 110.31(A)—which deals with electrical vaults, including their construction requirements—would apply. Often, we see vaults being utilized as electrical rooms for installations over 1000 volts versus the under-1000-volt installations. This is in part due to electrical installations using exposed terminations or the use of larger substations and switches, which could increase the risk of accidental contact with live parts, depending on the type of equipment. Construction of enclosures  Construction of the vault roof and walls must not be made from studs or wall board, but instead from construction materials that will provide adequate structural strength for the conditions and possess at minimum a 3-hour fire rating. This is usually accomplished using materials that are made from or contain concrete, like a masonry block wall with pre-cast concrete planks for the roof and floor, or a complete pre-cast concrete unit. Where the floor is in contact with earth it must not be less than 4-inch-thick concrete. However, where vacant space or stories are below the floor, it may need to be engineered to be able to structurally withstand the loads imposed on the floor. A vault will normally have access doors as well, which are required to be tight-fitting and have a 3-hour fire rating, unless the vault has an approved fire suppression system installed, in which case the doors can be 1-hour fire rated. These doors must also be lockable, to restrict access to unqualified persons. To allow safe egress in the event of an electrical injury, the doors must be equipped with panic hardware and open 90 degrees in the direction of egress. Don’t forget the signage that must be on the doors (See Part 2 in this blog series for more on signage). Should an electrical catastrophic failure occur, the vault’s robust construction will help mitigate damage to other portions of the building, which could ultimately save lives. This type of heavy-duty construction requires detailed planning from the electrical contractor and design professional for all electrical equipment locations and the penetrations into the vault from feeders, branch circuits, or raceways that will be connecting to that electrical equipment. These penetrations must not reduce the rating of the vault. The electrical equipment contained in the vault, such as the switchgear, transformers/substations, and motor control centers (MCC), must meet the working space requirements found in 110.26, 110.32, and 110.34 of the NEC. The applicable NEC section is determined by the highest nominal voltage for the equipment in a particular area, since there may be more than one voltage within a vault. Where high-voltage equipment is contained within the same vault as equipment 1000 volts or less, there may need to be some separation in accordance with 110.34(B). If the separation is accomplished with a fence controlled by locks, then 110.31 would apply. Table 110.31 contains distance values for the required space between the equipment and the separating fence. Note that the fence cannot be within the working space measurements found in Table 110.34(A). Adding electrical equipment in a vault does not reduce the working space requirements found in 110.26 or 110.34. It just adds some additional items to work around. Whether your electrical equipment is in an electrical room or a vault, you must maintain proper clearances for worker safety. A great way to learn more about working space about electrical equipment is to register for the NFPA online training series on the 2023 edition of the NEC. Working space about electrical equipment is covered in the General Equipment Installation Practices section of this training. Learn more about this comprehensive, self-paced training.