Where Do We Start?
When I talk to maintenance managers, electricians, and safety leads, there are a couple of questions that always surface: “Where do we start?” and “How often should we be doing maintenance procedures?”
The answer to both questions can be found by taking an in-depth look at your electrical system. Under the 2023 NFPA® 70B® standard, the process starts with the Equipment Condition Assessment. Understanding the condition of the electrical system is the foundation for determining maintenance intervals and prioritizing efforts.
In this post, we’ll walk through which conditions NFPA 70B mandates assessing and how those feed into interval decisions. Future blogs will dig into each condition (physical, criticality, environment) and how to assign them in practice.
NFPA 70B’s Three Dimensions of Equipment Condition Assessment
The structure of this assessment is rather straightforward and simple. NFPA 70B requires that you evaluate each piece of electrical gear across three distinct equipment condition parameters:
- Physical Condition
- Criticality Condition
- Operating Environment Condition
Each condition gets ranked on whether it meets the parameters of Condition 1, Condition 2, or Condition 3. The highest of those three becomes the “governing condition” for that equipment. For example, if both physical and operating environment are Condition 1, but Criticality is Condition 2, then you will use the intervals for Condition 2 equipment across the board.
Let’s take a high-level look at what NFPA 70B says about each condition type.
Physical Condition Assessment
This assessment examines the inherent state of the equipment based on visual inspection, previous maintenance/test results, continuous monitoring, and maintenance interval compliance.
Condition 1 is for equipment that “appears in like-new condition,” with a clean, dry, tight enclosure; no unaddressed continuous monitoring alerts; no outstanding predictive maintenance recommendations; and a history of maintenance consistent with your electrical maintenance plan.
Condition 2 applies when one or more warning signs emerge: deviations in test results indicate the need for more frequent maintenance, notifications or alerts flagged by continuous monitoring systems, active predictive maintenance recommendations, or prior maintenance cycles that revealed issues requiring major component replacements or repairs.
Condition 3 is the “red flag” state: previous two maintenance cycles were missed or both cycles revealed issues or failures requiring major repairs, urgent predictive alerts, or unresolved continuous monitoring alarms.
While many folks might be resistant to labeling equipment “Condition 3” because it means performing maintenance more often, that designation is invaluable—it triggers more frequent oversight and signals risk to management and safety teams.
Criticality Condition Assessment
In addition to looking at the current physical condition of the electrical equipment, NFPA 70B also wants us to account for the critical nature of each piece of equipment. This is both from the aspect of criticality to safety and criticality to system reliability.
However, the way the standard lays this out is that the criticality decision is up to the equipment owner unless failure of the equipment poses a risk to personnel.
Condition 1 can be assigned to equipment whose failure would not pose a risk to safety, nor would it have a major impact on operations. Think of this condition being reserved for equipment that is okay to run to failure and be replaced when it breaks, such as a light bulb.
Condition 2 is something an equipment owner might want to use if the failure of the equipment doesn’t present a major safety risk to personnel but is critical to the operation of the facility, i.e., a motor control center feeding several industrial machines that manufacture automotive parts. If the MCC fails, the machines shut down and stop manufacturing but don’t pose a safety risk.
Condition 3 must be applied, however, whenever there is a safety risk to personnel due to equipment failure. A great example would be an electric motor-driven fire pump, which has much more stringent maintenance requirements than what NFPA 70B requires for other motors because of the safety impact of a failure.
Criticality of electrical equipment needs to be a big part of the conversation since the purpose of NFPA 70B found in section 1.2 is to provide for the practical safeguarding of persons, property, and processes from the risks associated with failure, breakdown, or malfunction, and a means to establish a condition of maintenance of electrical equipment and systems for safety and reliability.
Operating Environment Condition Assessment
This dimension accounts for external stressors on electrical equipment: temperature, humidity, dust, chemical exposure, vibration, etc. Even well-maintained equipment in a harsh environment may need more frequent attention.
Condition 1 can be assigned to equipment that is appropriately rated for the environment in which it is installed. Outdoor equipment is used in outdoor locations, corrosion-resistant materials are used in corrosive environments, etc. However, it is highly recommended that Condition 1 only be applied when the operating environment is fairly calm and clean.
Condition 2 can be applied to equipment that is rated for the environment but maybe the environment is harsh, extremely corrosive, dirty and dusty, etc. This allows for more frequent check-ups on equipment to ensure that the environment is not having an impact.
Condition 3 must be applied when the equipment is installed in an environment that it is not rated for, i.e., an indoor panelboard installed in an outdoor location or EMT raceways installed in corrosive environments without corrosion protection.
The operating environment can have a major impact on the safety and reliability of an electrical system. Keeping a close eye on equipment installed in harsh environments or in an environment for which it is not rated can keep us on top of issues before they become a problem. Of course, if the equipment isn’t rated for the environment, the approach should always be to replace it with equipment that is rated for the environment.
Determining the Maintenance Task Intervals
Once the three assessments have been made, the job then becomes to assign a condition to the equipment for the purpose of determining maintenance task intervals.
NFPA 70B makes this simple. Whichever score is the highest drives the interval decisions. For example, if the physical and operating environments are both Condition 1 but the criticality is a Condition 3, then maintenance tasks must be performed at the frequency timeframe for the Condition 3 column in Table 9.2.2. This keeps maintenance in the proactive realm for equipment that has the potential to cause injury to personnel should it fail, which, in my opinion, seems like a reasonable and logical approach.
The Foundation Is Laid
This is the foundation of building a written electrical maintenance plan. Once we understand the equipment we are working with, we can formalize an approach that is based both on safety and reliability that is customized for the equipment we have and how we use it.
In upcoming blogs, we’ll unpack each condition dimension in depth—how to evaluate equipment for physical condition, how to determine criticality, and how environment should guide your classification.
Until next time, stay safe and always remember to test before you touch.
NFPA 70®, National Electrical Code®, NEC® , 70E®, and Standard for Electrical Safety in the Workplace® are registered trademarks of the National Fire Protection Association, Quincy, MA.
