"Plumbing Contractor" means a contractor whose contracting business consists of the execution of contracts requiring the experience, financial means, knowledge, and skill to install, maintain, repair, alter, extend, or, when not prohibited by law, design plumbing. A plumbing contractor may install, maintain, repair, alter, extend, or, when not prohibited by law, design the following without obtaining any additional local regulatory license, certificate, or registration: sanitary drainage or storm drainage facilities; venting systems; public or private water supply systems; septic tanks; drainage and supply wells; swimming pool piping; irrigation systems; or solar heating water systems and all appurtenances, apparatus, or equipment used in connection therewith, including boilers and pressure process piping and including the installation of water, natural gas (excluding liquid petroleum gases), and storm and sanitary sewer lines; and water and sewer plants and substations. The scope of work of the plumbing contractor also includes the design, when not prohibited by law, and installation, maintenance, repair, alteration, or extension of airpiping, vacuum line piping, oxygen line piping, nitrous oxide piping, and all related medical gas systems; fire line standpipes and fire sprinklers to the extent authorized by law; ink and chemical lines; fuel oil and gasoline piping and tank and pump installation, except bulk storage plants; and pneumatic control piping systems, all in such a manner as to comply with all plans, specifications, codes, laws, and regulations applicable. The scope of work of the plumbing contractor shall apply to private property and public property, shall include any excavation work incidental thereto, and shall include the work of the specialty plumbing contractor. Such contractor shall subcontract, with a qualified contractor in the field concerned, all other work incidental to the work but which is specified herein as being the work of a trade other than that of a plumbing contractor. Nothing in this definition shall be construed to limit the scope of work of any specialty contractor certified pursuant to s.489.113(6).