Army · MOS history

54B4 Chemical Operations Specialist

Converted to 74D, dated September 1, 2004 by the source.

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74DChemical, Biological, Radiological, and Nuclear (CBRN) Specialist

Documented history

Chemical Operations Specialist

DA Pam 611-21 Table 10-4 maps predecessor MOSC 54B4 to 74D; source successor entries: 74D CHEMICAL, BIOLOGICAL, RADIOLOGICAL AND NUCLEAR (CBRN) SPECIALIST; conversion effective 01 Sep 2004.

Source documents (1)

DA Pam 611-21, chapter 10, Table 10-4, Enlisted MOS Conversion Listing
1. Table 10-4, PDF p. 269 · source dated 2025
PDF page 269 (opens in a new tab)

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