# Massachusetts — US boiler and pressure vessel inspection requirements by state

For Massachusetts, governing body is Department of Fire Services, Chief of Engineering Inspections; statute citation is The General Laws of Massachusetts, Part I. Administration of the Government, Title 20. Public Safety and Good Order, Chapter 146. Inspection of Boilers, Air Tanks, etc; power boiler inspection interval is One annual internal inspection; One annual external inspection with boiler in service at approximately a six-month interval from the internal inspection; low-pressure boiler inspection interval is Hot-water heating and hot-water supply boilers: One inspection annually; One internal inspection every three years where construction permits; pressure vessel inspection interval is Air tanks: one internal inspection every two years, recorded from its source on 2026-08-05.

- **State:** Massachusetts _(verified: appears in the quote below)_
- **Governing body:** Department of Fire Services, Chief of Engineering Inspections
- **Statute citation:** The General Laws of Massachusetts, Part I. Administration of the Government, Title 20. Public Safety and Good Order, Chapter 146. Inspection of Boilers, Air Tanks, etc. _(verified: appears in the quote below)_
- **Power boiler inspection interval:** One annual internal inspection; One annual external inspection with boiler in service at approximately a six-month interval from the internal inspection.
- **Low-pressure boiler inspection interval:** Hot-water heating and hot-water supply boilers: One inspection annually; One internal inspection every three years where construction permits.
- **Pressure vessel inspection interval:** Air tanks: one internal inspection every two years.
- **Accepted inspector types:** Inspections, except first inspections, made by inspectors employed by Authorized Inspection Agencies and commissioned by the department are accepted in lieu of inspections made by a department inspector.
- **Exemptions:** All boilers, refrigeration and air conditioning systems, except when under the jurisdiction of the federal government. Heating boilers having less than 4 square feet grate surface; having a steam capacity less than 104 pounds per hour; used as a hot-water heating boiler with an output capacity less than 200,000 BTU per hour; used as a hot-water (or other liquid) supply boiler, having a heat input less than 200,000 BTU per hour, a water (or other liquid) temperature less than 200°F or a nominal water-containing capacity less than 120 gallons. Air tanks with inside diameter less than 6 inches; operating pressure less than 50 psi; or capacity less than 1 cubic foot.

## What the source says

> The General Laws of Massachusetts, Part I. Administration of the Government, Title 20. Public Safety and Good Order, Chapter 146. Inspection of Boilers, Air Tanks, etc. RULES FOR CONSTRUCTION AND STAMPING Construction:

## Source

- https://www.nationalboard.org/PrintAllSynopsis.aspx?Jurisdiction=Select

Last verified: 2026-08-05. Review by: 2027-08-05.
Part of [US boiler and pressure vessel inspection requirements by state](https://referencesource.org/boiler-inspection-requirements-by-state/).