Revision and assessment
0 of 3 hands-on
01 Introduction
This lesson brings the course together. Use the tables and cards to check what you remember, try the review questions, and then take the final exam when you feel ready.
Objectives
- Recall the main ideas about training, planning, checks, buddies, signals, gas, conditions and aftercare
- Apply them to short dive scenarios
- Prepare for the final exam
02 Watch
A dive from start to finish
4 min · Video in production
- 1
A whole dive assembled step by step: plan, check, entry, descent, dive, ascent, exit and log.
- 2
A quick recap of each lesson in a single picture and sentence.
- 3
A pair of divers deciding to cancel a dive because the conditions are too rough.
- 4
A preview of the exam format and pass mark.
03 Learn
The course at a glance
| Topic | Key idea | Habit |
|---|---|---|
| Training | Knowledge, confined water and open water, with an instructor | Dive within your training, and get a medical check if in doubt |
| Planning | Depth, time, gas, signals and what-ifs, agreed with your buddy | Plan the dive and dive the plan. Deepest dive first |
| Pre-dive checks | BCD, weights, releases, air and final check | Check yourself and your buddy, in the same order every time |
| Entries, descents and ascents | Equalise early. Never hold your breath on ascent | Slow and controlled, with a safety stop |
| Buddies | A buddy is help, a second set of eyes and a second source of gas | Stay close. If lost, search, then ascend and meet at the surface |
| Communication | A small set of standard signals | Always answer a signal |
| Gas | Depth makes gas go faster. Plan a turn pressure and reserve | Check your gauge often and end early if needed |
| Conditions | Current, waves, visibility, temperature and site type | Ask locally and say no when in doubt |
| Marine life | Look, do not touch | Good buoyancy prevents most injuries |
| Problems | They grow from small ones | Stop, breathe, think, act |
| After the dive | Rest, hydrate, log, wait before flying | Report any unusual symptoms at once |
A dive in ten steps
- 1.Check conditions, and agree the plan with your buddy.
- 2.Assemble your kit and check it, then check each other's.
- 3.Enter the water, regroup and check in at the surface.
- 4.Descend slowly, equalising early and often.
- 5.Dive within the plan, checking gas and your buddy regularly.
- 6.Turn at the agreed pressure, or sooner if anyone wants to.
- 7.Ascend slowly, breathing continuously, and make a safety stop.
- 8.Exit, check in and tell the crew how you feel.
- 9.Rest, hydrate and log the dive.
- 10.Rinse and dry your equipment.
Quick numbers
- Pressure rises by about 1 bar every 10 metres, so gas is used at twice the surface rate at 10 metres and three times at 20 metres.
- A typical ascent rate is no more than about 9 to 10 metres a minute, with a safety stop of about three minutes at 5 metres.
- A common turn pressure is about half of a full cylinder, with a reserve of at least about 50 bar.
- A typical minimum wait before flying is 12 hours after a single dive, and 18 hours or more after repeated or multi-day diving.
- A 1 knot current moves at about 30 metres a minute, faster than most divers can swim.
Take a guess first
A diver starts with 200 bar, turns at half, and wants to keep a 50 bar reserve. If they use gas evenly, how many bar do they have to spend on the return from the turn to the surface, before touching the reserve?
04 Explore
Try it yourself
Test yourself: flip each card to check the answer.
Flip each card to check your answer.
Tap a card to flip it.
05 Apply
Scenario
You and your buddy plan a boat dive to 18 metres. At the surface, the current is stronger than the briefing suggested, and the guide says that it is still within limits for experienced divers. You have 15 dives. You feel a little uneasy, and your buddy is keen.
What is the sensible way to approach it?
06 Check
07 Summary
Key points
- Dive within your training, plan with your buddy and check your kit and each other.
- Descend slowly and equalise, never hold your breath on ascent, and make a safety stop.
- Manage gas with a turn pressure and reserve, and respect the conditions.
- Look after yourself after the dive, and report any unusual symptoms at once. When you are ready, take the final exam.
Before you apply this in the water
- Have I been trained by a qualified instructor for this?
- Am I medically fit to dive?
- Do I have a buddy and a plan?
- Am I diving within my training and limits?
Answer every question in the Check section to mark this lesson complete.