National Electrical Code (NEC) is a set of regularly updated standards for the safe installation of electric wiring in the United States. First published in 1897, the NEC is updated once every three years.
The NEC provides guidelines for electrical installation in order to prevent fires and other electrical accidents. Electricians and contractors need to be aware of NEC where applicable to ensure that installations are safe, legal and up to code. The codes are a part of the National Fire Protection Association, a private trade association.
Despite its authoritative positioning and national title, NEC standards are not federal law. Instead, NEC standards are either adopted by local governments or local governments create and enforce their own electric code. The differing codes in various states are therefore something for contractors and electricians to remain aware of.
A major consideration in the design of a data center is whether the Information Technology Equipment (ITE) space will comply with Article 645 of the National Electrical Code. Article 645 covers equipment, power supply wiring, equipment interconnecting wiring, and grounding of information technology equipment and systems. NEC articles can be a controversial issue when it comes to the data center because certain articles of code such as the requirement for multiple E-Stops (also known as emergency power off buttons or EPOs) have been the cause of accidental downtime.