OCEAN DIVER KNOWLEDGE REVIEW OT4 PLANNING TO GO DIVING

OCEAN DIVER KNOWLEDGE REVIEW
OT4 PLANNING TO GO DIVING

Multiple-choice exercise

What useful purpose does nitrogen fulfil in the human body? See Student Workbook p38.
1. It carries oxygen to the tissues
2. It removes carbon dioxide from the tissues
3. None
4. It transports food to the tissues
5. It removes waste from the tissues
In a normal state our bodies are saturated with nitrogen, and when diving, increasing ambient pressure results in -------- nitrogen absorption. See Student Workbook p38.
1. More
2. Less
3. The same amount of
On ascent the ambient pressure falls and this causes the tissues to -------- nitrogen. See Student Workbook pp38-39.
1. absorb more
2. release
3. expand with
4. dissolve
5. neutralise
A sudden drop in pressure (a fast ascent) may not give enough time for a safe release of nitrogen.This can result in a medical condition called _____. See Student Workbook p39.
1. Nitrogen narcosis
2. HPNS
3. Hypercapnia
4. Decompression Illness
5. Nitrogen poisoning
Nitrogen will be released during an ascent, and at what other time? See Student Workbook p39.
1. At the deepest part of the dive
2. During the descent
3. After the dive, on the surface
Which of the following tissue types releases nitrogen quickly? See Student Workbook p38.
1. fat
2. cartilage
3. heart
4. tendons
5. bones
If you dive to one of the following depths, you will not be at risk from DCI, no matter how long you dive. See BSAC 88 Tables
1. 5m
2. 10m
3. 15m
4. 20m
5. 25m
A dive for which the table indicates no need for a decompression stop or stops during the ascent is called a _____. See Student Workbook p41.
1. wall dive
2. safe dive
3. rectangular dive
4. no stop dive
5. decompression dive
You can find no stop times for given dive depths by looking in _____. See Student Workbook p41.
1. the Ocean Diver Student Workbook
2. Your log book
3. A set of tide tables
4. BSAC '88 Decompression Tables
5. Safe Diving
An Ocean Diver is qualified to use the BSAC '88 Decompression Tables to _________. See Student Workbook p41.
1. Eliminate the possibility of getting DCI
2. Plan decompression stop dives
3. Plan dives to 25m
4. Plan no-stop dives to a maximum of 20m only
5. Plan extended range diving
The correct rate of ascent to 6m is ________ . See Student Workbook p40.
1. 18 metres per minute
2. 10 metres per minute
3. 20 metres per minute
4. 3 metres per minute
5. 15 metres per minute
Arriving at 6m during the ascent you should ________. See Student Workbook p40.
1. Descend
2. Ascend immediately
3. Pause then take 1 minute to ascend
4. Pause then ascend to 3m
5. Ascend to 3m and then pause
If you dive to a maximum depth of 6m, what is your no stop time? See BSAC 88 Tables
1. 243 minutes
2. 376 minutes
3. 479 minutes
4. 480 minutes
5. Unlimited
Dive time is _____. See Student Workbook p40.
1. The total elapsed time of the dive
2. The time between the start of descent and the start of ascent
3. The time between the start of descent and reaching 6m on the ascent
4. The time between the start of descent and the deepest point of the dive
5. The time between the end of the descent and the start of the ascent
What does the Surfacing Code describe? See Student Workbook p40.
1. The length of the dive
2. The depth of the dive
3. The length of the decompression stop
4. The diver's tissue saturation level (nitrogen) on surfacing from the dive
5. The time till flying in an aeroplane is allowed
What is the Surface Interval? See Student Workbook pp41-42.
1. The time between the start of one dive and the start of the next
2. The time between surfacing from one dive and descending on the next
3. The distance between two dive sites
4. The distance necessary to swim out to start a descent
5. The time necessary to wait before flying in an aeroplane after diving.
The Current Tissue Code indicates: See Student Workbook pp41-42.
1. Which Table the diver can now use to make a dive
2. The level of nitrogen saturation at the end of the previous dive
3. The length of time necessary for the Surface Interval
4. The depth of the current dive
What is the ascent check depth for a no stop dive? See Student Workbook p40.
1. The depth at the end of the dive before ascending
2. The depth at the level of your first decompression stop
3. 9m
4. 6m
5. Surface
No stop dive times are coloured ______ on the BSAC '88 Tables? See Student Workbook p41.
1. pale yellow
2. pale blue
3. white
4. pale green
5. grey
When calculating decompression, if you are in doubt about the exact depth, you should _____. See Student Workbook p41.
1. Use the shallower increment
2. Use the deeper increment
3. Add 3m as a safety precaution
4. Add 6m as a safety precaution
5. Round up to the next even number
You should always plan to surface with ------ still in your cylinder. See Student Workbook p49.
1. 25% of your breathing gas
2. 50% of your breathing gas
3. 33% of your breathing gas
When using decompression tables you need _____. See Student Workbook p43.
1. A Dive Computer
2. Accurate counting of fin strokes
3. Ascent in line with your small exhaust bubbles
4. A depth gauge and watch
5. A high level of physical fitness
Enjoyable and trouble free dives are dives which are _____. See Student Workbook p50.
1. shallow
2. local
3. deep
4. planned
5. abroad
Which of the following points will NOT contribute to the avoidance of a diving incident? See Student Workbook pp37-50.
1. Practice of personal skills
2. Buying the most expensive equipment
3. Planning the dive
4. Buddy and self monitoring
5. Diving with an experienced buddy
Plan the dive and __________ See Student Workbook p43.
1. Plan the lunch
2. Dive the plan
3. Dive the wreck
4. Plan to dive
5. Dive the dive
Which of the following statements about safe decompression is correct? See Student Workbook pp45-46
1. In a series of dives do the deepest one at the end
2. Dehydration is only a problem in hot climates
3. Avoid saw tooth dive profiles
4. Diving with a hangover is uncomfortable but harmless
5. If you are cold you are less likely to get DCI
6. You can get DCI even if you stick rigidly to your tables/computer
You fly into your dive destination. How long should you wait before diving? See Student Workbook p42.
1. 1 hour
2. 16 hours
3. 8 hours
4. 24 hours
5. 10 hours
You have been on a diving holiday. How long should elapse from the end of your last dive to the flight? See Student Workbook p43.
1. 1 hour
2. 16 hours
3. 8 hours
4. 24 hours
5. 12 hours
Which of the following is the basic function which enables a dive computer to perform decompression calculations? See Student Workbook pp43-44.
1. Water temperature
2. Age of diver
3. Fitness of diver
4. Exertion of diver
5. Mathematical model of nitrogen uptake in the tissues
The advantage to the diver of a multi level dive computer in comparison to decompression tables is that the computer takes into account _____. See Student Workbook pp44-45.
1. The physical condition of the diver
2. The water conditions on the dive
3. The actual dive profile
4. The actual exertion used during the dive
5. The individual characteristics of the diver
What Nitrox mixes can an Ocean Diver use? See Student Workbook p46
1. 21%
2. 27%
3. 32%
4. 36%
5. 40%
Which decompression tables can an Ocean Diver use when using Nitrox? See Student Workbook pp46-47.
1. BSAC Nitrox Tables Air (21% Oxygen) set
2. BSAC 88 Tables Level 1
3. BSAC Nitrox Tables 32% Oxygen set
4. BSAC Nitrox Tables 36% Oxygen) set
5. BSAC 88 Tables Levels 2-4
What is the advantage to an Ocean Diver of using Nitrox as a breathing gas? See Student Workbook p46.
1. Longer no-stop times
2. Reduced equipment servicing costs
3. No need to worry about equipment contaminants
4. Greater safety factor against DCI
5. Cheaper gas fills
Just before diving with a cylinder of Nitrox you should always ________. See Student Workbook p48.
1. hyperventilate
2. purge your demand valve
3. analyse the mix
4. take an aspirin
5. wash your hands
Nitrox cylinders require special materials and greases, and periodic cleaning in order to minimse the _________. See Student Workbook pp47-48.
1. cost of servicing
2. risk of fire and explosion
3. risk of bacteria growth inside
4. weight of the cylinder
5. need for special labelling
Nitrox cylinders must be marked with the _______? See Student Workbook p48.
1. Owner’s name
2. Gas blender’s name
3. Pressure of the current fill
4. Percentage of oxygen
5. Percentage of nitrogen
You should ________ your gas supply throughout a dive. See Student Workbook p50.
1. monitor
2. conserve
3. share
4. ignore
5. breathe
Which of the following statements about using an oxygen analyser is correct? See Student Workbook pp48-49.
1. always calibrate in air first
2. keep the flow rate high
3. erratic readings are normal: use best of 3, best of 5, etc
4. analysis should be within +/- 1% of the target mix
5. analysers are robust and generally unaffected by adverse conditions
6. read the manual