PADI IDC Exam Example Questions and Answers

Note these are not official PADI questions but are similar to the ones that you would be expected to know, they have been created by myself when Staffing IDCs to give to give to students when they wanted more example / sample exam and test questions. There are plenty of multiple choice test questions in your open water manuals and in the Knowledge Development Workbooks if you have a copy of them. I would also recommend looking at the dive master exams again.

Here is a selection of exam questions and answers that you should tackle in exam conditions to test your dive knowledge. Remember dive theory wont take up 100% of your time when you are a PADI Dive Instructor (OWSI) but you need to know it 100% and actively encourage people to learn more about it.

A good teaching tip is to reference what your students have learned in class when they are in the water, for example when you talk about descending, say something like "remember we learned about water pressure and the effects it has on our body today in the classroom? well when we descent the increasing weight of the water will have the following effects on us...............".

Example PADI IDC and IE Exam Questions

Some are common dive knowledge and some are multiple choice questions (Metric and Imperial). Use either metric or imperial numbers when figuring out your answers. Some RDP questions are listed twice (metric and imperial versions).

How many confined water sessions and open water sessions are there in an Open Water course? 
5 and 4

To Participate in DLD experience the participant must do what ?
Read / Sign a Liability release and assumption of risk form
What is the normal full pressure of a recreational scuba tank ?
200 bar / 3000 PSI (there are 15 psi per bar) 
For your information: Most countries apart from the US use Bar as a measurement of pressure for tanks

What is the pressure of a tank that began with 200 Bar and was slowly opened and left for hours until it was empty ?  
1 Bar (most people think 0 Bar, but unless you live in a vacuum it's the normal atmospheric pressure at sea level which is 1 Bar)

 Which program has a Open water Dive Ration of 10:1   ? 
Skin Diver

According to Henry's law, what causes something to absorb more gases into solution?
Salty water
PressureDensity
Lung Capacity

What are the two basic parts of a regulator called?
The two basic parts of a regulator are called the first and second stage.

According to Charles' law, what increases as the temperature of a gas increases?
Density
Speed 
Pressure
Volume

At what depth will you reach 2ATM of pressure?
33ft or 10m

To reduce the risk of decompression sickness (DCS – nitrogen bubbles blocking blood circulation/flow in your body after a dive):
a) ascend (go up) to a shallower depth if you feel dizzy and thirsty
b) have your tank filled only at a dive center you trust.
c) breathe more slowly than normal using Nitrox
d) make a safety stop at 5 metres (15 feet) at the end of each dive.e) use Nitrox / Enriched Air on every dive

You make two dives in one day and you are flying home on a commercial plane. What is the minimum time you have to wait before you can go on the plane?
a) 36 hours
b) 24 hours
c) You do not have to wait.
d) 18 hours

Certified DMs must complete how many DSD Internships to be qualified to conduct them ?  
4 DSD Programs
What is Confined water ?
look this one up but its basically a pool or a body of water with pool like conditions
Underwater most sounds seem to come from where ? 
overhead

In the unlikely event that you are in an out-of-air situation (OOA), and you are close to your dive buddy, the best thing to do is to:
a) make a controlled emergency swimming ascent (CESA – swim up to the surface saying the ah-h-h sound).
b) buddy breathe (share a single regulator with your buddy).
c) switch to your buddy's alternate air source - Remember to do the out of air sign.
d) panic and rush to the surface 
e) use the air in your BCD.

note: if you answered d then this is obviously wrong and dangerous

How do you avoid CNS Oxygen Toxicity
Don't exceed an oxygen PP of 1.4 ata

What percentage of Air is Oxygen ?
21%

What are Heat Exhaustion Signs & Symptoms?
Weak, rapid breathing, weak rapid pulse, profuse sweating, skin cool and clammy, nausea

What is a Visual Inspection  ?
Checks for damage and wear / allows for maintenance and lubrication – is a dive industry standard

How does a  transducer work and where would you find one?’
Varying an electrical current depending on the pressure exerted on it – Dive Computers have transducers in them

When do waves break ?
Waves Break when approaching the shore – When the depth is the same height as the wave

What is the most common reason for Cylinders slipping in nylon tank bands?
Due to adjusting the band while it was dry

The rate at which a theoretical tissue absorbs and releases nitrogen is called its?
Halftime.

Can you can rely on a Haldanean Deco model?
Only as far as it has been shown to work in test and by field experience

What are waves caused by?
Wind

What causes currents in the bodies of water around the world?
Wind and the earth's rotation.

What causes Tides?
Gravitational pull of the Earth and the Moon.

did you know that - Pressure Gradient is greater at Altitude that's why different procedures must be adopted over 300m.

What are the Signs and Symptoms of Oxygen Toxicity?
VENTID - Don't know what that means ? carry on reading your books :)
Once you get your Instructor Manual look through the Standards section (at the front) and familiarise yourself with its layout and content, look up stuff like ages for courses, depths etc

Imagine you were diving from a dive boat (common in most dive resorts) and get caught in a strong current at the surface. Should you?
a) Descend (go down) and try to swim against the current near the bottom.
b) Make yourself buoyant / float, then signal the boat for help, and try to swim against the current.
c) Make yourself positively buoyant and float, signal for help, rest and wait for the boat to pick you up.d) Try to swim against the current by staying just below the surface.

Most scuba diving injuries caused by fish and aquatic animals happen because:
a) the marine animal is trying to protect itself and is scared of you
b) the animal is aggressive and wants to hurt you.
c) the animal wants to mate with you.
d) the animal thinks you are dinner!

Decompression Sickness types and general areas affected?
DCS1 Pain Only 
DCS2 Nervous System

Divers who act strangely or foolishly at depth may start acting normal again if they:
a) breathe slowly and deeply.
b) ascend (go up) to a shallower depth.
c) signal their buddy for help.
d) All of the above.

You are likely to increase the risk of decompression sickness (DCS) if:
a) you do not look after your equipment.
b) you are tired, cold, sick, thirsty or overweight.
c) you dive in poor visibility, strong moving water, and rough seas.
d) All of the above.
e) a and c only

 
METRIC — RDP table or eRDP: You dive to 17 metres for 23 minutes. After a 30 minute surface interval, you plan to dive to 16 metres. What is the maximum allowable time for the second dive?
a) 10 minutes
b) 61 minutes
c) 51 minutes
d) 27 minutes

METRIC — RDP table or eRDP: You are a newly qualified instructor and you are planning to make two dives. The first dive is to 21 metres for 30 minutes, and the second dive is to 15 metres for 36 minutes. How long would you have to stay on the surface between dives (minimum surface interval) to do these two dives safely?
a) 9 minutes
b) 1 hour and 4 minutes
c) 29 minutes
d) Instructors do not need to wait between dives

METRIC — RDP table or eRDP: You dive to 17 metres for 44 minutes. After a one hour surface interval you do a second dive to 17 metres. Losing track of time, you notice your bottom time is now 37 minutes. What should you do?
a) Ascend (go up) right away to 5 metres and stay there for 8 minutes before going to the surface.
b) Go to the surface right away and contact the nearest recompression chamber.
c) Ascend (go up) right away to 5 metres and stay there for 3 minutes before going to the surface then drink lots of fizzy drinks on the boat.
d) Ascend (go up) to 3 metres and stay there until you use up your air.

IMPERIAL — RDP table or eRDP: You dive to 59 feet for 22 minutes. After a 30 minute surface interval, you plan to dive to 50 feet. What is the maximum allowable time for the second dive?
a) 10 minutes
b) 61 minutes
c) 29 minutes
d) 59 minutes

IMPERIAL — RDP table or eRDP: You are a newly qualified instructor and you are planning to make two dives. The first dive is to 21 metres for 30 minutes, and the second dive is to 15 metres for 36 minutes. How long would you have to stay on the surface between dives (minimum surface interval) to do these two dives safely?
a) 49 minutes
b) 1 hour and 4 minutes
c) 2 hour and 32 minutes
d) Instructors do not need to wait between dives

IMPERIAL — RDP table or eRDP: You dive to 17 metres for 44 minutes. After a one hour surface interval you do a second dive to 17 metres. Losing track of time, you notice your bottom time is now 37 minutes. What should you do?
a) Ascend (go up) right away to 5 metres and stay there for 8 minutes before going to the surface.
b) Go to the surface right away and contact the nearest recompression chamber.
c) Ascend (go up) right away to 5 metres and stay there for 3 minutes before going to the surface then drink lots of fizzy drinks on the boat
d) Ascend (go up) to 3 metres and stay there until you use up your air.

If you descend and then you find your ears or sinuses hurt while you are going down, it normally means:
a) your air spaces are equalized (cleared).
b) your mask strap is too tight.
c) you are feeling a squeeze and need to equalize.
d) your mask is too small.
e) hurting ears are fine and you should get used to it as a diver.

You should not even consider diving if you currently have a cold or are suffering from any allergies because:
a) you will get your Doctor in trouble for clearing you to dive.
b) you may become tired or seasick easily.
c) you may not be able to equalize pressure in your body air spaces.
d) you will use your air up too fast.
e) you may become unconscious (dazed, out cold) without warning.

If you hold your breath while scuba diving can:
a) damage your lungs
b) preserve your air so you can dive for longer
c) push air into the blood stream and chest area.
d) give yourself life threatening injuries.
e) a, c and d

You should skip breath when
a) you want to preserve your air
b) your buddy is better at preserving his or her air
c) tank refils are expensive in your area
d) never

Heat Stroke –What do you do ?  
Cool diver and get him to medical aid station

What are the conditions caused by the failure of body's temp maintenance systems?
Hypothermia and heat stroke

A forceful Valsalva and delayed middle ear equalisation can cause what ? 
Ear - Round window rupture

What is the most important rule in scuba diving? - if you don't know this give up now :)
a) diving is great at getting rid of hangovers
b) Always perform a pre dive safety check.
c) Establish positive buoyancy and relax when at the surface.
d) Never dive alone.
e) Breathe continuously and never hold your breath.f) find cool people to dive with.

If you are having to work too hard and find it difficult to breathe underwater, you should:
a) get to the surface quickly by inflating your BCD.
b) stop your diving and rest, hold onto something for support if possible.
c) swim right away to your buddy and signal for help.
d) do a controlled emergency swimming ascent (CESA - swimming up to the surface giving it the the ahhhh sound).
e) try a different hobby like ping pong
f) dont let anyone see as its embarrasing to suck at diving

  Divers are most affected by CONDUCTION. Least affected by RADIATION.

You know you are properly weighted for diving if you:
a) are the first to the reef from the boat.
b) sink slowly holding a normal breath of air and an empty BCD.
c) float at eye level holding a normal breath of air with an empty BCD.
d) float at neck level with your BCD about half full and you are holding a normal breath of air.
e) desend as slowly as the largest person in your dive party. 

If you and your dive buddy were separated / couldn't find each other underwater what would you generally do?
a) Check your air and tailor your search pattern depending on how much you have left.
b) Find your buddy's bubbles and follow the bubbles to find your buddy.
c) Go up right away, wait a minute and then go back down underwater.
d) Search for a minute underwater and then go up to find your buddy.
e) Go to the surface right away and get out of the water. 

Imagine you feel a mild current at the start of your dive. How should you begin this dive?
a) Drink lots of coffee and fluids as your in for a tough dive
b) Dive against or into the current.
c) Never dive with a current.
d) Dive in the direction of the current (taking it easy :) )e) Dive across the current. 

 Shallow Water Blackout caused by Hypocapnia due to a falling oxygen partial pressure.

Best time to dive ? 
Slack tide after a high tide

 Eustachian tube leads to the middle ear (from the throat)

What is the water pressure at 34m in Fresh water (.97) ? 
Absolute and Ambient  4.3 ATA / Gauge 3.3 ATM

You should be able to answer these simple open water questions without the answers, if you cannot then re-read the open water manual, you should also be able to explain why the wrong answers are not correct to someone that thinks that they are correct!

Still want more questions? good, have a look here for more general knowledge and some sample PADI IDC / IE quiz / exam questions and answers

I am a great believer on the fact that you don't really know something until you can teach someone else about that subject, think about describing water pressure on ears or air consumption at depth to a student. Practice this often with fellow students, start by saying ‘teach me about…………' and then ask each other questions, it's the best way to learn.

Now you are at the end, hopefully you will have a better understanding of Dive Theory, if you can answer all your PADI quizzes and exams and complete the Knowledge development workbooks and your ‘mock' exams in the Instructor Manual then you will be fine on the theory, if you are worried about the practical skills and demonstrations / teaching presentations then get help from your local dive center and perhaps you want to consider doing a pre-idc preparation courses that most Course Directors offer.

 

Good Luck, Dive safe and look after yourself and your future divers, you always remember your first certification and I hope you get as much out of it as we did.