MASSACHUSETTS
MA Sheet Metal Master: 9
MA Sheet Metal Instructor: 2181
MA Sheet Metal Business: 814
MA Refrigeration Contractor: RC-148026
MA Master Electrician: 10192
MA Master Plumber/Corp: 3003
MA Master Gasfitter: MPL 13469
MA Master Plumber: MPL 13469
MA Oilburner Tech: BU-062081
MA Pipefitting PHCP-W: PM-023745
MA Master PP: PM-297362
MA Construction Supervisor (CSL): CS-103116
NEW HAMPSHIRE
NH Business Mechanical: MBE1000460
NH Master Gasfitter: GFE0801176
NH Master & Elec Corp: 7163M
NH Master Plumber: 4231
RHODE ISLAND
RI Refrigeration Master: 5047
RI RI EL master and Corp: A-0055238 B-015099
RI RI EL Contractor: A-005238
RI Master Plumber: MP007614
RI Pipefitter/Master 1: PM 00008914
CONNECTICUT
CT Master Electrician: ELC.0208749-E1
CT S1: HTG.0408438-S1
CT Master Plumber P1: PLM.0282498-P1
MAINE
ME Master Plumber: MS90012474
ME Gas Fitter: PNT10472
ME Master Electrician: 16437
Updated as of February 2026