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Skills and Environment

Scubacat IDCWaves

1.Capillary waves – very small.
2. Storm waves – large – 30 m +.
3. Wind causes waves.
4. Only the wave shape or energy moves.
5. The effects of the wave stops at a depth of 45m.
6. Waves are measured by height and length.
7. When a wave is as deep as its height, bottom friction slows the forward speed, it bunches up becomes higher / steeper then breaks.
8. They cause a ripple affect on the sand running parallel to the shore (handy for natural navigation)


1. Twice daily.
2. Tides result from gravitational interaction between the earth, sun and moon.  Also topographical features.
3. The moon has most effect.
4. Tidal wave results from seismic activity.


1.Coriolis effect – Northern Hemisphere – deflections to the right.
2.As a result water piles up in the middle of the pacific ocean.
3.Northern hemisphere trade winds blow from the NE to SW.
4.Currents negligible at depths of 190m.
5.Wind energy and the coriolis effect drives the ocean currents.
6. Northern hemisphere major ocean currents flow clockwise.
7.Southern hemisphere major ocean currents flow counter-clockwise.
8. The major current in the southern hemisphere turn: counterclockwise
9. Best time to diving: slack tide when high tides peaks
10. Currents are caused by wind and the earth’s rotation
11. Tides are caused by: the gravitational interaction of the earth, moon and sun


1. Trust your compass: even if you think you are going to the wrong direction
2. Triangle: 120 degrees for each corner
3. Reciprocal heading on a compass means: 180 degrees from the initial heading
* Natural navigation, directional information: plants, animals, bottom composition (rocks, sand ripples…), light and shadow

Altitude Diving

1. RDP can be used using the Theoretical Depth at Altitude Chart from: 300 meters to 3000 meters
2. Ascent rate when diving in Altitude is: 9 meters per minute
3. If you want to do two dives in different altitude: the first must be in the highest altitude.
4. To use the RDP: only with special procedures
5. Altitude Diving: Capillary depth gauge
6. Planning an altitude dive: actual depths must converted to theoretical depths to find the pressure group
7. Special procedures:
– Nitrogen narcosis may occur at shallower depth
– The ambient atmospheric pressure at altitude is less than at sea level
– Actual depths must be converted to theoretical depths to find no decompression limits on the RDP

General information

1 CPR compression ratio for Adult, child and infant: 30/2
2 Use a lifting device, weight recommended: 4-7 kilos
3 Maximum depth for recreational diving is: 40m
4 CESA: must keep all the equipment in place, surfacing while emitting a continuous AHH sound
5 Recommendation for Safety Stops: at the end of every dives
6 Night Dives: one dive light but recommended that each divers 2 lights
7 Marine life injuries includes: respiratory depression or arrest, local swelling,
inflammation, severe pain, numbness, paralysis, cardiac arrest
8 Alternate air source: should be placed between the chin and the corners of your rib cage
9 Difference between DCS and Lung overexpansion is: DCS tends to appear a few hours after, Lung overexpansion upon surfacing

Boat Terminology


Front of the Boat is called the Bow
Back of the boat is called the Stern
Left is Port
Right is Starboard
Head is the Toilets
Galley is the Kitchen


Winward is towards the boat
Leeward is away from the boat (so if your feeling a bit unwell best stand Leeward)


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