Del. Code Ann. tit. 24, § 6118
Nothing in this chapter shall be construed to prevent the performance of service and repair of any elevator in any structure by individuals working in a manufacturing or industrial facility, who are all of the following:
83 Del. Laws, c. 469, § 1; 70 Del. Laws, c. 186, § 1; 84 Del. Laws, c. 493, § 1