Is Chapter 1 of the NEC important? It has only two Articles. The first one is (yawn) definitions. Nobody has time to sit around reading dictionaries, so you can’t seriously be expected to read this, right? If you come across a word you don’t know, you can always look it up, right?
The problem with that mindset is many of these definitions impart important concepts. Take, for example, the ongoing confusion over grounding and bonding. In installations where grounding is done instead of the required bonding, dangerous differences of potential exist. These errors are responsible for costly power quality problems, equipment reliability issues, premature motor failures, nuisance breaker trips, “annoyance” electrical shocks, flashovers, and, in severe cases, electrocution.
Yet all this can be avoided by simply understanding (and being able to recall while on the job) the definitions of grounding (basically, connecting to the earth) and bonding (basically, creating a metallic path). Other examples of “you really need to understand Article 100 definitions” abound. There’s a very good reason these appear in the very first Article rather than in a glossary in the back of the NEC.
The second Article, 110, provides a bunch of general requirements. Aren’t these already accounted for in your drawings and procedures? Maybe, maybe not. You could take Art. 110 into almost any manufacturing facility or commercial building and walk out with a list of violations.
Try this at your facility, and see what you come up with. For starters, look for enclosures that have unused openings that aren’t closed [110.12(A)]. There are many more specifics. Being unfamiliar with Chapter 1 just sets you up for “code confusion” and all the problems that entails.
Studying Chapter 1 a little bit each week is one way to become familiar with it.