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Navy · RATING history

BT Boiler Technician

The Navy's Boiler Technician (BT) rating merged into the Machinist's Mate (MM) rating effective October 1, 1996.

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Documented history

Boiler Technician

October 1, 1996 is the merger's effective date. August 1998 is the publication date of the GAO report documenting it.

  • The GAO report confirms the merger and date, but the implementing personnel directive is not available here to establish any detailed transition rules.
Source extraction notes

GAO footnote 13 states that the Boiler Technician rating merged with the Machinist's Mate rating as of 1 Oct 1996. This is an official reproduction, not the unrecovered implementing personnel directive.

Source documents (1)

Reviewed September 23, 2026 against reference 1.

Boilerman

In 1964, Boilerman (BT) and MM were combined at pay grade E-9 to form Master Chief Steam Propulsionman (SPCM). This does not establish that the BT rating ended at lower pay grades.

The combination is dated to 1964; no month or day is given.

  • The Master Chief Steam Propulsionman rating was disestablished in 1968; no month or day is given.
Source extraction notes

Malin/BUPERS source assertion: Established 1964; combination of BT and MM ratings at E-9. Normalized as merged/included. The source explicitly limits this combination to pay grade E-9; it does not assert that lower-pay-grade use of the predecessor rating ended.

Source documents (2)

Reviewed September 23, 2026 against references 1, 2 and 4.

Historical information is drawn from the sources linked above. Classification dates are not personal service dates. Spot an error? Let us know.