| Acronym | Meaning |
| OWIC | Open Water Instructor Course (BSAC) |
| BT | Bottom Time |
| SI | Surface Interval |
| DIR | Doing It Right |
| ITW | Instructor Training Workshop (BSAC) |
| MDL | No Decompression Limit |
| PDIC | Professional Diving Instructors Corporation International; Diving Instruction Organization. |
| IDEA | International Diving Educators Association; Diving Instruction Organization. |
| AD | Adventure Diver (PADI) Advanced Diver (BSAC) |
| RDP | Recreational Dive Planner |