Section R. 339.5175 - Boiler repairers; classes of licensesRule 175.
(1) A class I license allows a licensee to repair a low-pressure boiler by means other than welding, riveting, or other fabrication process.(2) A class II license allows a licensee to do both of the following:(a) Repair a low-pressure boiler, a hot water supply boiler, and a fire tube boiler of any pressure.(b) Perform work covered by a class I license.(3) A class III license allows a licensee to do all of the following: (a) Repair a high-pressure boiler.(b) Repair or replace non-boiler external piping, as defined by ASME code B31.1 and R 339.5209.(c) Perform work covered by a class II license.(4) A class IV license allows a licensee to do both of the following: (a) Repair or field-erect a boiler of any pressure, except for a boiler that has a nuclear hear source.(b) Repair or replace non-boiler external piping as defined by ASME code B31.1 and R 339.5209.(5) A class V license allows a licensee to erect and repair a boiler or its parts that has a nuclear heat source, appurtenances, or system components, and also provides that the licensee may repair or replace non-boiler external piping, as defined by ASME code B31.1 and R 339.5209. Before a license is issued, an applicant for a class V license shall submit evidence of the following: (a) Familiarity with and knowledge of all federal rules and regulations regarding the construction of a boiler that has a nuclear heat source.(b) Employment by a company in possession of a valid ASME N-type symbol stamp applicable to the portions of any nuclear boiler system he or she proposes to repair.(6) A class P license qualifies a person to install or repair non-boiler external piping as defined by ASME code B31.1, 2018, and R 339.5209.Mich. Admin. Code R. 339.5175