Tex. Utilities Code § 55.003: RULE OR STANDARD.

(a) A public utility may not impose a rule except as provided by this title.

(b) A public utility may file with the commission a standard, classification, rule, or practice the utility follows.

(c) The standard, classification, rule, or practice continues in force until:

(1) amended by the utility; or

(2) changed by the commission as provided by this subtitle.

Acts 1997, 75th Leg., ch. 166, Sec. 1, eff. Sept. 1, 1997.