This subtitle does not apply to:
(1) persons employed by a public utility or by the United States government, while those persons are performing work on installations or systems on or within buildings or structures owned or occupied by a public utility or by the United States government; or
(2) a person, firm, or corporation engaged in the installation, maintenance, repair, or replacement of refrigeration, air conditioning or heating equipment in motor vehicles or railroad rolling stock.
(1985 Code, Art. 20, § 5-102) (Bill No. 1-12)