Massachusetts Refrigeration License

When Massachusetts Requires a State Refrigeration License

Massachusetts does not require a state refrigeration license for every system. Outside the exemptions in 522 CMR 9.00, including private residences and apartment houses with fewer than five apartments, the threshold is aggregate capacity: if the refrigerant-containing systems you are working on total ten tons or more, you must hold a license issued by the Office of Public Safety and Inspections (OPSI) under 528 CMR. Below ten tons, a federal EPA Section 608 certification is sufficient for the refrigerant-handling side (though you still need other trade licenses for ductwork, gas, and electrical connections).

The "aggregate" part is critical. Multiple mini-split or VRF units in a single building connected through a communication port or building management system have their capacities combined. Four three-ton mini-splits linked to a common BMS equals twelve tons — and that pushes the project into OPSI territory.

The Three License Tiers

Refrigeration Apprentice. You must register your apprenticeship with the Division of Apprentice Standards (DAS) and simultaneously hold an active OPSI apprentice license. Both registrations must be concurrent — hours logged without an active OPSI apprentice license are void and will be rejected when you apply for the technician exam. Application fee: $40. Biennial renewal: $20, limited to two renewal cycles unless otherwise approved by the Bureau.

Refrigeration Technician. This lets you perform refrigeration work independently on systems of ten tons or greater. To qualify for the exam, you need documented apprentice OJT hours plus classroom instruction. For applications dated and received before November 9, 2026, candidates can choose from three pathways: 6,000 OJT hours with 250 classroom hours, 4,000 OJT with 500, or 2,000 OJT with 1,000. The exam is closed-book with a 70% passing score, administered after OPSI reviews your application (expect four to eight weeks). Application fee: $75. Biennial renewal: $50.

Refrigeration Contractor. Required to contract for refrigeration work, establish a business, and employ other technicians. You need at least 2,000 hours of journeyman experience plus 100 additional training hours beyond the technician level. Application fee: $150. Biennial renewal: $75.

The November 2026 Training Rule Change

Applications dated and received on or after November 9, 2026, must meet a single unified standard: 6,000 OJT hours and 450 classroom hours (300 refrigeration theory plus 150 Massachusetts electrical code). The flexible pathways — the 2,000-hour and 4,000-hour options — disappear for applications dated on or after that cutoff. A hardship exception exists at the Bureau's discretion but expires entirely on May 10, 2027.

If you are currently accumulating apprentice hours under one of the shorter pathways, the deadline matters. Get your application in before November 9, 2026.

Applying Through MyLicenseOne

All refrigeration license applications go through the OPSI MyLicenseOne portal at madpl.mylicenseone.com. You will need a high school diploma or equivalent, a 2x2 passport photo, a copy of your Universal EPA 608 card, and signed employer work verification forms. OPSI has moved to digital-only licenses — no more printed cards in the mail.

The Massachusetts HVAC License Guide walks through the complete application sequence, the concurrent-registration requirement, and how to avoid the most common documentation mistakes that delay OPSI approvals.

See more Massachusetts guides →