Scuba

Front 1

An object is neutrally buoyant when it

Back 1

neither sinks nor floats

Front 2

An object that does not sink or float in fresh water will probably ____ in salt water

Back 2

float

Front 3

A diver is 20 meters/66 feet underwater. The water pressure at this depth would be ___ times greater than the pressure at the surface

Back 3

three

Front 4

I hold a glass upside down at the bottom of a swimming pool; I fill it completely with air from my scuba cylinder and then take it to the surface without tipping it. As I ascend (go up), the air in the glass will

Back 4

expand (air molecules will move further apart)

Front 5

What can happen if I do not follow the most important rule in scuba diving?

Back 5

my lungs can over-expand, which could cause serious injury

Front 6

What should I do if I have pain in one or both ears while I am descending (going down)?

Back 6

Ascend until the soreness or pain goes away; if I can't equalize, do not continue the dive

Front 7

I put air into a balloon at 10 meters/33 feet and then take it to the surface. The balloon will

Back 7

expand to twice the size it was at 10 meters/33 feet

Front 8

I want to look after all of my scuba equipment. One way to help prevent the inside of my cylinder from corroding is to

Back 8

never let it empty completely

Front 9

when rinsing a regulator, do not

Back 9

press the purge button if it is not attached to a cylinder with the air turned on

Front 10

What is the main reason I can't use swimmer's goggles for scuba diving?

Back 10

D. I can't equalize goggles

Front 11

When I look at objects through water and through a mask, they seem

Back 11

larger

Front 12

____ travels fast underwater and I may have difficulty telling where it came from

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sound

Front 13

If I get cold while scuba diving and I can't stop shivering (shaking), what should I do?

Back 13

stop diving immediately, get out of the water, dry off and change into something warm

Front 14

Being properly weighted, attaching hoses and gauges out of the way so I am streamlined and moving slowly and steadily

Back 14

is the best way to move underwater

Front 15

Wet suits keep me warm as long as the water is trapped between my skin and the suit. To cut down on the water moving in and out of my wet suit I should

Back 15

wear a suit that fits properly

Front 16

Proper airway control allows me to

Back 16

breathe past small amounts of water that may be in the snorkel or regulator

Front 17

While swimming against the current at the surface, I begin to feel fatigue, anxiety and weakness, and my breathing becomes labored. These are symptoms of

Back 17

overexertion

Front 18

My buddy and I should conduct the predate safety check

Back 18

after gearing up, but before entering the water

Front 19

When I practice the buddy system, my buddy and I will

Back 19

make predive safety checks

Front 20

Making a safety stop at the end of a dive helps me

Back 20

stabilize my ascent rate and gives my body tissues extra time to release

Front 21

For the most part, how far I can see underwater is determined by sunlight and _____

Back 21

suspended particles (floating silt) in the water

Front 22

Without a reference line, compass or depth gauge I am most likely to become disoriented on my dive

Back 22

in midwater

Front 23

I am diving from a boat and I am caught in a strong current at the surface and can't get back to the boat. I should

Back 23

float at the surface (become positively buoyant) and signal for help

Front 24

I am more likely to be injured by an aquatic animal if I

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touch animals, even if they look harmless

Front 25

Dive environments differ from each other. It is recommended that when I dive in a new or unfamiliar location that I

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get an area orientation

Front 26

I am helping a diver who is struggling at the surface. I should begin by

Back 26

establishing buoyancy for myself and the diver

Front 27

A non breathing diver at the surface requires immediate

Back 27

rescue breaths

Front 28

If I have a problem at the surface I should

Back 28

make myself float right away

Front 29

If available, give ____ to a diver who is breathing but unresponsive

Back 29

oxygen

Front 30

If I feel ill before a dive, I should

Back 30

cancel the dive

Front 31

To reduce the risk of contaminated air (bad air) problems, I should have my cylinders

Back 31

filled only by a reputable dive center

Front 32

T or F

Your dive log should contain information that will make planning subsequent dives easier

Back 32

TRUE

Front 33

bubbles blocking blood circulation (flow) in my body after a dive are caused by

Back 33

excess nitrogen gas coming out of solution

Front 34

Common signs and symptoms of decompression sickness (DCS) include

Back 34

pain, weakness, and inability to move arms and/or legs

Front 35

When using a dive computer, I should not ascend any faster than

Back 35

the rate specified by my computer

Front 36

To avoid oxygen toxicity when diving with air, I should

Back 36

not exceed the maximum depth for recreational diving

Front 37

to plan a dive with a computer, I typically start by

Back 37

activating the no stop scroll mode

Front 38

When diving with a computer

Back 38

each diver needs an individual computer

Front 39

Before I do anything else with my dive computer, I should

Back 39

read the manufacturer's instructions

Front 40

buoyant emergency ascent- dropping my weight system

Back 40

When my buddy is too far away and I'm deeper than 9 meters/30 feet

Front 41

buoyant emergency ascent - dropping my weight system

Back 41

When my buddy is too far away

Front 42

controlled emergency swimming ascent (CESA) - swimming up to the surface making a continuous sound (like ahhhh)

Back 42

When I am low on air and not out of air

Front 43

normal ascent - going up normally

Back 43

When my buddy is near

Front 44

As I descend, I need to equalize air spaces. Which of the following are accepted ways of equalizing my ears?

a. block my nose and attempt to gently blow through it

b. swallow and wiggle the jaw from side to side

c. block my nose and blow forcefully for an extended period of time

Back 44

a & b

Front 45

during a descent, I try to equalize, but discover I am having trouble doing so. What should I do?

Back 45

Stop my descent, signal my buddy, ascend slightly and try again

Front 46

I should equalize

Back 46

early and often, before I feel discomfort

Front 47

T or F

I should not dive with a cold, nor use medications to dive with a cold

Back 47

True

Front 48

the most important rule in scuba diving is

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breathe continuously and never hold my breath

Front 49

T or F

Failure to follow the most important rule in scuba diving can cause serious lung over expansion (lung rupture) injuries, which in turn can cause paralysis and death

Back 49

True

Front 50

If I feel discomfort in a body air space while ascending, the correct action is to

Back 50

stop, descend slightly and give trapped air time to work its way out

Front 51

My buddy and I are planning a dive to 18 meters/60 feet. We would expect our air supply to last ____ at 10 meters/33 feet, all else being the same

Back 51

shorter than

Front 52

During a dive, I swim hard to keep up with a fish that interests me, but shortly begin to feel like I can't get enough air. The correct action would be to:

Back 52

stop all activity and rest to restore proper deep, slow breathing

Front 53

T or F

The 3 overall benefits of the buddy system are practicality, safely, & fun

Back 53

True

Front 54

The primary considerations when choosing my scuba gear are:

Back 54

suitability, fit, & comfort

Front 55

I'm planning to dive the following week and am checking my gear. I put my kit together and notice that my regulator seems to breathe harder than I remember. The appropriate action would be to:

Back 55

Have it inspected and serviced as needed by a professional before using it

Front 56

T or F

there is no way to use a DIN regulator on a yoke cylinder valve

Back 56

false

Front 57

T or F

It is important to master buoyancy control because it allows me to control whether I descend, float, or am neutrally buoyant. I adjust my buoyancy frequently while diving.

Back 57

True

Front 58

While underwater, I want to move efficiently by

Back 58

being streamlined, swimming slowly & steadily, and maintaining proper trim

Front 59

If I am with one buddy, but can't see the other, What should I do?

Back 59

This is a buddy separation. Stay with the remaining buddy and search for no more than a minute, then reunite on the surface

Front 60

My buddy and I are planning a shore dive. We are descending onto a very gradual slope that begins at 5 meters/15 feet, so our descent and ascent will be a gradual part of swimming out and back underwater. We have similar cylinders filled to 200bar/3000 psi. We plan:

- 50 bar/500 psi reserve

- 20 bar/300 psi for our safety stop

- to turn the dive when we've used 1/3rd of the air available to use on the dive

This means we should head back when either of our SPG's read

Back 60

157 bar/2270 psi

Front 61

S.O.R.T.D.

Back 61

Signal

Orient

Regulator

Time

Descend

Front 62

My buddies and I are wearing wet suits for exposure protection. As I descend, my buoyancy will ____, so I should ____ to control my buoyancy

Back 62

decrease, add air frequently to my BCD in small amounts

Front 63

I should never descend or ascend without a reference that I can follow or make contact with

Back 63

false

Front 64

While boat diving, my buddy and I finish our safety stop and ascend to the surface. When I reach the surface, I should

Back 64

inflate my BCD, switch to my snorkel & signal okay to the divemaster

Front 65

One way to avoid disorientation while descending and ascending is to

Back 65

follow a reference

Front 66

My buddy and I are diving from a boat and there's a mild current. In most circumstances, we would ____ for the first part of the dive

Back 66

swim into a current

Front 67

My buddy and I accidentally find ourselves in a rip current. There are no special, local procedures so we should

Back 67

inflate our BCD's and swimming parallel to shore

Front 68

T or F

Depending upon my location, tides can cause significant changes to depth, currents and visibility, or they may have hardly any effect

Back 68

True

Front 69

T or F

I should stay well away from the boat propeller at all times, even when the engine isn't running

Back 69

true

Front 70

On a dive at 10 meters/30 feet, I fail to watch my sPG and run out of air. My buddy is 12 meters/40 feet away and has an alternate second stage. My best option is to probably

Back 70

make a controlled emergency swimming ascent

Front 71

** Knowledge Review 4

Back 71

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