=jwelectric,
Welcome to The Building Codes Forum!
From the `08 NEC, Article 90.4:
This Code is intended to be suitable for mandatory application
by governmental bodies that exercise legal jurisdiction over
electrical installations, including signaling and communications
systems, and for use by insurance inspectors.....The authority
having jurisdiction for enforcement of the Code has the
responsibility for making interpretations of the rules, for
deciding on the approval of equipment and materials, and
for granting the special permission contemplated in a number
of the rules......By special permission, the authority having
jurisdiction may waive specific requirements in this Code
or permit alternative methods where it is assured that
equivalent objectives can be achieved by establishing and
maintaining effective safety........This Code may require
new products, constructions, or materials that may not
yet be available at the time of the Code is adopted.....In
such event, the authority having jurisdiction may
permit the use of products, constructions, or materials
that comply with the most recent previous edition of
this Code.
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