SCUBA Chapter 1

a depth change of 10 metres/33 feet causes a pressure change of

1 bart/ata

If you take 6 litres of air from the surface to 29 metres/66 feet, the volume with be _______ litres.

2

Two basic fin styles are ________________fins.

Adjustable and full-foot

Which of the following are among the breathing rules I follow as a diver? Breathe continuously and never, ever, hold my breath. Breathe slowly and deeply. Do not allow myself to get winded or out-of-breath. If faced with a problem, stop, then maintain or restore slow, deep breathing.

All

To control my buoyancy, normally I will use my weight system and my

BCD

As a descend, I need to equalize air spaces. Which of the following are excepted ways of equalizing my ears? Block my nose and attempt to gently blow through it, swallow and wiggle the jaw from that side to side, block my nose and blow forcefully for an extended period

Block my nose and attempt to gently blow through it, swallow and wiggle the jaw from that side to side,

The most important rule in Scubadiving is:

Breathe continuously and never hold my breath

The ____________ is a safety device that relieves accidental over pressure by releasing air before reaching the pressure at which the cylinder would fail.

Burst disk

Complete the following depth-pressure-air volume-air density table: Depth pressure volume density 0 m/0 feet 1 bar/ETA 1 ×1 10 m/33 feet ______________ 1/2 ___ 30 m/99 feet ______________ 1/4 ___ 40 m/132 feet 5 bar/88 ______ ×5

Depth pressure volume density 0 m/0 feet 1 bar/ETA 1 ×1 10 m/33 feet 2 bar/ATA 1/2 ×2 30 m/99 feet 4 bar/ATA 1/4 ×4 40 m/132 feet 5 bar/88 1/5 ×5

I should equalize

Early and often, before I feel discomfort

The most important consideration when choosing a regulator is

Ease of breathing

T/F: There is no way to use a DIN regulator on a yoke cylinder valve.

False

T/F: There's no real benefit to choosing the components of my school packet as an integrated package.

False. Although the components are generally interchangeable, choosing your scuba kit as a package helps you best meet your preferences.

T/F: From among masks that fit me, I should choose a mask that fits as far away from my face as possible.

False. Choose a low profile that's as close to your face as possible.

T/F: Salt water causes more buoyancy than fresh water because it is less dense and weighs less

False. Salt water causes more buoyancy because it is more dense and weighs more; buoyancy results from the weight of the water displaced.

My SPG is always part of my dive computer

False. Your SPG may be independent instrument or it may be integrated into your dive computer.

An object that is neutrally buoyant in freshwater will ______________ in salt water.

Float

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

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

I'm renting a Scuba cylinder at a dive resort. Among the cylinders for hire, some have green and yellow bands that read night trucks. As a PADI open water diver with no other training or instructor supervision, am I qualified to use one of these cylinders?

No

My sunglasses case falls out of my pocket into the water, but fortunately, it floats so I retrieve it. I would say my sunglasses case is ______ buoyant

Positively

Most important feature in my weight system is its

Quick release

I bring a cylinder aboard a dive boat in preparation for a trip out to a nearby reef. The normal procedure would be to

Secure the cylinder in a rack

When setting up and wearing my kit, the alternate air source

Secures in the triangle formed by my hips and chin

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

Shorter than

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

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

During a descent, I try to equalize but discover I'm having trouble doing so. Which of the following is correct? Slow my dissent, signal my body to slow down, and equalize more forcefully. Stop my descent, signal my buddy, ascend slightly and try again. Continue my descent while equalizing repeatedly. Signal my buddy, ascend to the service and start my descent over.

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

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

Stop, descend slightly and give trapped air time to work it's way out.

The primary considerations when choosing any piece of scuba gear are:

Suitability, fit, and comfort

T/F: A cylinder with a higher working pressure always holds more air than a cylinder with a lower working pressure.

True

T/F: Buoyancy is a force that pushes an object in water upward

True

T/F: Failure to follow the most important rule in scuba diving can cause serious lung overexpansion (lung rupture) injuries, and which in turn can cause paralysis and death.

True

T/F: Failure to follow the most important rule in scuba diving can cause severe lung overexpansion injuries, which can result in paralysis or death.

True

T/F: Fins provide a large surface area so my legs can push against the water effectively.

True

T/F: Getting the service my gear needs may be a consideration when choosing equipment

True

T/F: I equalize gently because an extended, forceful equalization can cause permanent damage to my ears and hearing

True

T/F: I must be able to quickly release enough weight to float reliably in an emergency, but not necessarily all my weight.

True

T/F: I should not dive with a cold, or use medications to dive with a cold.

True

T/F: In recreational diving, the buddy system means diving with another diver or divers in a team that provides assistance and safety benefits.

True

T/F: It is important to master buoyancy control because it affects almost everything I do in and underwater.

True

T/F: It is important to master points the control because it allows me to control whether I just sent, float, or I'm neutrally buoyant. I just my buoyancy frequently well diving.

True

T/F: My BCD should have adequate capacity to easily float my equipment and me at the surface.

True

T/F: My LPI mechanism inflates the BCD with air from my scuba cylinder.

True

T/F: My body responds to anxiety with increased breathing, but slow breathing helps reduce anxiety.

True

T/F: My local dive pro will usually set up my regulator components

True

T/F: One reason for wearing more than one way system is that it is sometimes easier than handling a single, heavier one.

True

T/F: Regulators need periodic overhauls typically every year to two years

True

T/F: Snorkels our standard equipment for Scubadiving because they allow me to breathe with my face in the water, or in rough condition, without wasting my scuba air, especially when I have a little scuba air remaining.

True

T/F: Some scuba divers prefer a snorkel with a flexible lower portion so it drops out of the way when not in use.

True

T/F: The three overall benefits of the buddy system or practicality, safety, and fun.

True

T/F: To prepare adjustable fins, I should adjust the straps wearing my wetsuit boots.

True

T/F: When scuba diving, normal breathing keeps your lungs equalized to the surrounding pressure

True

My buddy is rinsing a BCD and partially filled the bladder with water. Is this consistent with recommended BCD care?

Yes

A squeeze is caused by

a pressure imbalance between the surrounding pressure and an air space

I want to adjust my mask so the strap rests

above my ears, over the crown of my head

Equalization is the process of

adding air to an air space

When choosing an alternate air source, a primary consideration involves deciding

between independence and simplicity

My primary considerations when choosing fins are fit and

blade size

A balloon fully inflated and sealed at 10 metres/33 feet, would probably ______ during ascent to the surface

burst

Accessory weights

can help you adjust your trim

On a day I plan to go diving, I wake up with my sinuses blocked due to a cold or allergy. I should

cancel the dive until I'm well

The three most important considerations in choosing scuba equipment are suitability, fit and ______________.

comfort

When I descend, my buoyancy tends to ________. When I ascend, it tends to _______.

decrease, increase

The most efficient way to breathe dense air underwater is to breathe

deeply and slowly

Trim means having the right ________ of weight

distribution

My mask encloses my nose so I can

equalize my mask

scuba cylinders require pressure testing _______, and visual inspection _________

every 2-5 years, annually

My buddy and I descend to 12 metres/40 feet. I would expect to use my air _______ at 6 metres/20 feet

faster than

My BCD should fit

fit snugly but not restrict breathing when fully inflated

As you descend in water the pressure

increases

Underwater when I inhale, my buoyancy

increases slightly

Before each use I should ________ my equipment

inspect

As I descend, increasing pressure affects my

mask, ears, sinuses

I need a mask because

my eyes must be in air to focus

I should have my scuba cylinder filled

only by reputable scuba air stations

When my snorkel is in my mouth, the tip should be

over the crown of my head

Overall benefits of the buddy system include

practicality, safety and fun

I'm descending and discover I can't equalize. The first thing I would do is

stop my descent and signal my buddy/the instructor

During ascent I feel discomfort in my ears. I should

stop, descend slightly and allow trapped air to work its way out.

The density of the air in the previous question would be ___________ the density at the surface.

three times