| Acronym | Meaning |
| DCS | Decompression Sickness |
| OW(D) | Open Water (Diver) (PADI) |
| OWIC | Open Water Instructor Course (BSAC) |
| OD | Ocean Diver (BSAC) |
| PDIC | Professional Diving Instructors Corporation International; Diving Instruction Organization. |
| AA | Assisted Ascent |
| NI | National Instructor (BSAC) |
| BCD | Buoyancy Control Device |
| EFR | Emergency First Response |
| AIC | Advanced Instructor Course (BSAC) |