| Abbreviation | Definition |
|---|---|
| OTCS | Ocean Systems Technician Senior Chief Petty Officer |
| OTM1 | ean Systems Technician (manual) Chief Petty Officer |
| OTM1 | Ocean Systems Technician (manual) Chief Petty Officer |
| OTM2 | ean Systems Technician (manual) Petty Officer 1st Class |
| OTM2 | ean Systems Technician (manual) Petty Officer 2nd Class |
| OTM2 | Ocean Systems Technician (manual) Petty Officer 1st Class |
| OTM2 | Ocean Systems Technician (manual) Petty Officer 2nd Class |
| OTM3 | ean Systems Technician (manual) Petty Officer 3rd Class |
| OTM3 | Ocean Systems Technician (manual) Petty Officer 3rd Class |
| OTMSA | ean Systems Technician (manual) Seaman Apprentice |
| OTMSA | Ocean Systems Technician (manual) Seaman Apprentice |
| OTMSN | ean Systems Technician (manual) Seaman |
| OTMSN | Ocean Systems Technician (manual) Seaman |
| OTMSR | ean Systems Technician (manual) Seaman Recruit |
| OTMSR | Ocean Systems Technician (manual) Seaman Recruit |
| OTSA | Ocean Systems Technician Seaman Apprentice |
| OTSN | Ocean Systems Technician Seaman |
| OTSR | ean Systems Technician Seaman Recruit |
| OTSR | Ocean Systems Technician Seaman Recruit |
| P&F | Plumber & Fitter 1st Class Petty Officer |