(2) When acting pursuant to subsection (1) of this section, the Public Utility Commission shall adopt by rule as the standard of such construction, operation and maintenance the 1973 edition of the American National Standard, National Electrical Safety Code, C2.
(3) In lieu of subsection (2) of this section, or in addition thereto, the commission may adopt by rule any revision or edition of or amendment to the National Electrical Safety Code approved by the American National Standards Institute after July 14, 1977, and in effect on the date of adoption by the commission. [Amended by 1969 c.530 §1; 1971 c.655 §68; 1975 c.658 §1; 1977 c.346 §1]