(a) Persons holding a Restricted Gas Fitter Plumber's License for the particular phase of gas fitting shall not perform any plumbing service other than the restricted phase for which he is licensed.

(b) Persons holding a Restricted Gas Fitters Plumber's License shall not be eligible to use experience gained under such license to obtained credit toward other forms of licenses issued by the Department.

(c) Persons holding a Restricted Gas Fitter Plumber's License shall not transfer a license from one phase of plumbing to any other phase or move from one area of restriction to another without first submitting a new application to the Department.

(d) The Gas Utility License shall cover all of the utility's gas serviceperson for installation and service by the utility, providing that the utility requires each such serviceperson be specially trained for such service. The Utility shall be responsible to the Department for each serviceperson and shall provide an identification card showing the utility license name, utility license number and the restricted service of the serviceperson. The Utility shall register each serviceperson and their serial numbers with the Department. Such servicepersons are expressly not eligible for any gas work or service for other than the utility and in the name of the utility.