Tex. Health & Safety Code § 752.004
(a) Unless a person, firm, corporation, or association effectively guards against danger by contact with the line as prescribed by Section 752.003, the person, firm, corporation, or association, either individually or through an agent or employee, may not perform a function or activity on land, a building, a highway, or other premises if at any time it is possible that the person performing the function or activity may:
Acts 1989, 71st Leg., ch. 678, Sec. 1, eff. Sept. 1, 1989.