Scuba Section 1
A depth change of 10 metres/33 feet causes a pressure change of
1 bara/ata
Buoyancy is
a force that pushes an object in water upward
I want to adjust my mask so that the strap rests
above my ears, over the crown of my head
My buddy and I descend to 12 metres/40 feet. I would expect to use my air _______6 metres / 20 feet
faster than
Although the components are generally interchangeable, choosing your scuba kits a package helps
you best meet your preferences
If you take 6 litres of air from the surface to 20 metres/66 feet, the volume will be ___ litres
2
To control my buoyancy, normally I will use my weight system and my
BCD
The LPI mechanism inflates the
BDC with air from my scuba cylinder
I should equalize
Before I feel pain or discomfort
Which are among the breathing rule I follow as a diver
Breathe continuously and never hold breath Breathe slowly and deeply Do not get winded or out of breath If face with a problem, stop, then maintain or restore slow, deep breathing
The most important rule in scuba diving is to
Breathe continuously and never hold your breath
My mask encloses my nose so I can
Equalize the mask
What are the parts of a regulator
First stage (where you breath from) Primary second stage Alternate air source SPG/computer low pressure inflator hose
I'm renting a scuba cylinder at a dive resort. Among the cylinders for hire, some have green and yellow bands that read "Nitrox". As a PADI Open Water Diver with no other training or instructor supervision, am I qualified to use one of these cylinders
No, until you are a PADI open water diver and a PADI enriched air diver
During descent I feel discomfort in my ears, I should
Stop, descend slightly and allow trapped air to work its way out
My buddy is rinsing a BCD and partially fills 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
Equalization is the process of
adding air to an air space
My BCD should have
adequate capacity to easily float my equipment and me to the surface
To prepare adjustable fins, I should
adjust the straps wearing my wet suit boots
The two basic fin styles are
adjustable and full-foot
Your SPG may be
an independent instrument or it may be integrated into your dive computer
From among masks that fit me I should choose a mask that fits
as a low profile and sits as close to my face as possible
When choosing an alternate air source, the primary consideration involves deciding
between independence and simplicity
A balloon fully inflated and sealed at 10 metres/33 feet would probably ___ during ascent to the surface
burst
The ____ is a safety device that relieves accidental overpressure by releasing air before reaching the pressure at which the cylinder would fail
burst disk
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
When I descend buoyancy tends to ______. When I ascend it tends to ________
decrease increase
The most efficient way to breathe dense air underwater is to breath
deeply and slowly
Trim means having the right _____ of weight
distribution
The buddy system means
diving with another diver or divers in a team that provides assistance and safety benefits
scuba cylinders require pressure testing _______, and visual inspection _________
every 2-5 years annually
Salt water causes more buoyancy than fresh water because it is less dense and weighs less
false, it causes more buoyancy because it is more dense and weighs more
My primary considerations when choosing fins are
fit and blade size
My BCD should fit
fit snugly but not restrict breathing when fully inflated
I must be able to quickly release enough weight to
float reliably in an emergency, but not necessarily all my weight
A cylinder with a higher working pressure always
holds more air than a cylinder with a lower working pressure
As you descend in water the pressure
increases
Underwater when I inhale my buoyancy
increases slightly
Before each use I should ________ my equipment
inspect
One reason for wearing more than one weight system is that
it is sometimes easier than handling a single, heavier one
Fins provide a
large surface area so my legs can push against the water effectively
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
Regulators need
periodic overhauls, typically every year to two years
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
Overall benefits of the buddy system include
practicality, safety and fun
The most important feature in my weight system is
quick release
Identify the four systems that make up a scuba kit
regulator cylinder weight system BCD
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 it in a rack
When setting up and wearing my kit, the alternate air source
secures in the triangle formed by my hips and chin
I'm descending and discover I can't equalize. The first thing I would do is
stop my descent and signal my buddy/instructor
The three most important considerations in choosing scuba equipment are
suitability, fit and comfort
The most important consideration when choosing a regulator is
the ease of breathing
Snorkels are standard equipment for scuba diving because
they allow me to breathe with my face in the water, or in rough conditions, without wasting my scuba air, especially when I have little scuba remaining
Getting the service my gear needs may be a consideration when choosing equipment
true
I equalize gently because an extended, forceful equalization can cause permanent damage to my ears and hearing
true
It is important to master buoyancy control because it affects almost everything I do and underwater
true
My body responds to anxiety with increased breathing but slow breathing helps to reduce anxiety
true
My local dive pro will usually set up my regulator components
true
When scuba diving, normal breathing keeps your lungs equalized to the surrounding pressure
true