(1)    Limitations.

      (a)    Persons licensed as master plumbers (restricted), journeyman plumbers (restricted) or registered learners shall be classified by the department under sub. (2) and shall be restricted to the type of work for which they have been classified and to the requirements indicated in this section.

      (b)    Persons licensed as journeyman plumbers (restricted) or registered learners shall work under the supervision of a master plumber or a master plumber (restricted). A master plumber (restricted) may also work as a journeyman plumber (restricted). No journeyman plumber (restricted) or registered learner shall contract for work, advertise or do anything which would lead others to believe him to be qualified as a master plumber (restricted) in his classification.

      (c)    All persons licensed as master plumbers (restricted), journeyman plumbers (restricted) or registered learners shall be subject to all laws and rules governing plumbers. If qualified, persons may be licensed under any number of classifications under sub. (2). Separate licenses shall be issued under sub. (2) (a) and (b), but licenses issued under sub. (2) (b) may extend to any number of items under that paragraph.

   (2)   Classifications. The classifications which the department shall use are a sewer services classification and an “appliances, equipment and devices” classification. Persons so classified may engage in the following types of work:

      (a)    Systems or services. Persons classified under this paragraph may install septic tanks for private on-site wastewater treatment systems, may install drain fields designed to serve such septic tanks, and may install sewer service from the septic tank or sewer extensions from mains to the immediate inside or proposed inside foundation wall of the building. Such persons may also install water services, stormwater use systems, and reclaimed water systems if the services or systems are to be located outside the foundation wall of the building.

      (b)    Appliances, equipment or devices. Under this paragraph persons installing a water treatment device, a water heater, or any other item in connection with a water distribution system, including a stormwater use or reclaimed water system, which does not require a direct connection to a drain system are limited to making connections to existing installations. There shall be no drilling, tapping, or direct connection made to any waste or drain pipe to serve items installed under this section. The maximum length of water piping permitted to be installed under this section shall be the minimum required to connect the item to the system.