Must the conductor be grounded for AC premises wiring?

For AC premises wiring systems the identified conductor must be grounded.

[WSR 97-09-013, recodified as § 296-307-36621, filed 4/7/97, effective 4/7/97. Statutory Authority: RCW 49.17.040, [49.17.]050 and [49.17.]060. WSR 96-22-048, § 296-306A-36621, filed 10/31/96, effective 12/1/96.]

PDFWAC 296-307-36621

Must the conductor be grounded for AC premises wiring?