NATIONAL ELECTRICAL CODE NFPA 70
Article 90 is the Introduction to the National Electrical Code. As with most introductions, this article
is often skipped. To understand the NEC and its application better, it is very important that you
thoroughly read and review this article.
ARTICLE 90 INTRODUCTION
(a) Practical Safeguarding. The purpose of the NEC is the protection of persons and property by minimizing
the risks caused by the use of electricity. (b) Adequacy. The Code is intended for the application
of safety. When the rules of the NEC are complied with, an installation is expected to be essentially
free from hazards. However, installations complying with the NEC does not mean that the electrical
system will be efficient, convenient, adequate for good service, or that it will work.
(FPN, Fine Print Note) Hazards can occur because of overloading of circuits and improper installation
of equipment. These problems often arise because the original installation did not provide for future
expansion, which is not required by the Code.
CAUTION: The NEC does not contain any rule that requires consideration
for future expansion of electrical use. The NEC is concerned solely with safety: but, the electrical
designer must be concerned with safety, efficiency, convenience, good service, and future expansion.
Often, electrical systems are designed and installed that exceed NEC requirements. However, the inspector
does not have the authority to require installations to exceed the NEC requirements, unless adopted
by local ordinance. (c) Design or Instruction Manual. The Code is not a how-to book, it is not intended
as a design specification or an instruction manual for untrained persons.
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