| Acronym | Meaning |
| C-CARD | Scuba Diving Certification Card. |
| ITW | Instructor Training Workshop (BSAC) |
| OW | Open Water Certification; First Certification Level. |
| PPB | Peak Performance Bouyancy |
| SAA | Sub-Aqua Association |
| PG | Pressure Group |
| RNT | Residual Nitrogen Time |
| AA | Assisted Ascent |
| ITS | Instructor Training Scheme (BSAC) |
| DIN | Deutsches Insitut Fuer Normung |