Scuba Midterm

Seasickness is caused by: 1: Factors such as smell of salt water and the sound of boat engines. 2: A change in equilibrium in the middle ear. 3: An elevation in adrenaline levels caused by anxiety over diving. 4: None of the above.

A change in equilibrium in middle ear.

A regulator system may include: 1: A first stage and primary second stage. 2: An alternate air source second stage (or a connection to an alternate-air-source inflator on the BC). 3: A submersible pressure gauge (SPG), which is usually part of an instrument console. 4: All of the above.

All of the above.

Among the best ways to prevent decompression sickness (DCS): 1: Remain well within your dive computer's no-decompression limit. 2: Ascend no faster than the rate allowed by the dive computer. 3: Make a safety stop of between three and five minutes at a depth of 3-6 m/10-20 ft. 4: All of the above.

All of the above.

An additional type of squeeze divers may suffer is a: 1: Mask squeeze. 2: Tooth squeeze. 3: Reverse block. 4: All of the above.

All of the above.

Basic post-dive equipment maintenance and care includes: 1: Rinsing thoroughly with fresh water. 2: Allowing to dry completely. 3: Storing in a cool, dry place, away from direct sunlight. 4: All of the above.

All of the above.

Contributing factors to decompression sickness can include: 1: Rapid ascents. 2: 'Pushing" or exceeding your computer's no-decompression limits. 3: Heavy exertion and/or dehydration. 4: All of the above.

All of the above.

Not allowing alternate-air-source second stages, instrument consoles and other equipment to dangle freely: 1: Helps reduce the risk of entanglement. 2: Helps protect fragile aquatic life. 3: Helps protect equipment from damage. 4: All of the above.

All of the above.

Which of the following is/are true? 1: Tides can make the water at a particular dive site noticeably deeper or shallower than you may have experienced previously. 2: Tidal currents can be very strong, making diving difficult or even dangerous. 3: Strong tidal currents can have an adverse effect on visibility. 4: All of the above.

All of the above.

Which of the following statements is/are true? 1: A rip current is a narrow flow of swiftly moving water that runs perpendicular to shore. 2: Rip currents form when water flowing out to sea is funneled through a narrow restriction, such as two sandbars or a break in a coral reef. 3: The force of a rip current generally diminishes in deeper water, not far beyond the surf zone. 4: All of the above.

All of the above.

In terms of what BCs can help divers do, all of the following are true except: 1: Achieve positive buoyancy at the surface and maintain neutral buoyancy under water. 2: Provide a central attachment point for cylinders, regulators and accessories. 3: Allow divers to enjoy elevator-like rides to the surface 4: Generally incorporate a weight system.

Allow divers to enjoy elevator-like rides to the surface

The three As of buoyancy control include all of the following except: 1: Awareness. 2: Anticipation. 3: Appreciation. 4: Action.

Appreciation.

If you feel pain or discomfort during descent: 1: Stop, hold in place and equalize forcefully until your ears clear. 2: Ascend to the point where you can comfortably equalize, and only then continue your descent. 3: Abort the dive and consult a physician. 4: Note the depth at which the pain occurred and conduct your safety stop there at the end of the dive.

Ascend to the point where you can comfortably equalize, and only then continue your descent.

Before you can remove the regulator from your scuba cylinder, you must: 1: Turn the air all the way off. 2: Depressurize the system by depressing and holding one of the purge buttons. 3: Make sure the low-pressure inflator hose remains connected to the BC power inflator. 4: Both the first and second answers are correct

Both the first and second answers are correct

A regulator equipped with a conventional alternate-air-source second stage: 1: Is the among the most widely used and readily understood type of alternate air source. 2: Limits the receiver to using only the alternate-air-source second stage. 3: Allows the donor to give either second stage to an out-of-air diver. 4: Both the first and third answers are correct.

Both the first and third answers are correct.

Among the limitations of full foot fins: 1: They are not well suited for colder-water diving. 2: There are no full-foot fins sufficiently powerful for use with scuba equipment. 3: They are not well suited for entries from rocky shores. 4: Both the first and third answers are correct.

Both the first and third answers are correct.

Before adding air to your BC under water, you must: 1: Be thoroughly familiar with the location and operation of your BC's inflation/deflation mechanism(s). 2: Empty your lungs so that they do not affect your overall buoyancy. 3: Be ready to instantly vent air from you BC, should you accidentally add too much. 4: Both the first and third answers are correct.

Both the first and third answers are correct.

In the event your computer fails, and you are not carrying a back-up computer: 1: End the dive and make a slow ascent and safety stop. 2: Stop for two minutes at 6 m/20 ft and five minutes at 3 m/10 ft. 3: Do not get back in the water for at least 24 hours. 4: Both the first and third answers are correct.

Both the first and third answers are correct.

Objects under water appear: 1: Closer than they do on land. 2: Farther away than they do on land. 3: Larger than they do on land. 4: Both the first and third answers are correct.

Both the first and third answers are correct.

Slates are useful when you need to: 1: Communicate information that hand signals cannot. 2: Get your buddy's attention under water. 3: Temporarily record dive data for later transfer to a log book. 4: Both the first and third answers are correct.

Both the first and third answers are correct.

Which of the following is/are important features of a weight system? 1: The ability to quickly and reliably jettison at least enough weight to make the wearer positively buoyant at the surface or at depth. 2: The ability to carry a minimum of at least 25 kg/55 lbs of weight. 3: The ability to easily adjust the amount of weight used. 4: Both the first and third answers are correct.

Both the first and third answers are correct.

If you suspect that you or another diver is suffering from decompression sickness. 1: Drive yourself (or the affected diver) to the closest recompression chamber. 2: Activate the Emergency Medical Service (EMS) system. 3: Contact the Divers Alert Network (DAN). 4: Both the second and third answers are correct.

Both the second and third answers are correct.

Using your arms to swim under water: 1: Dramatically increases your overall speed and efficiency. 2: Somewhat increases your overall speed and efficiency. 3: Causes you to expend energy needlessly. 4: None of the above.

Causes you to expend energy needlessly.

Which type of alternate air source does not necessarily require the donor to give up his primary second stage? 1: Technical diving configuration. 2: Alternate-air-source inflator. 3: Conventional alternate-air-source second stage. 4: None of the above.

Conventional alternate-air-source second stage.

The primary function of a mask is to: 1: Magnify the appearance of objects under water. 2: Cover the nose, to prevent water from entering. 3: Create an air space in front of the eyes, enabling them to focus. 4: None of the above.

Create an air space in front of the eyes, enabling them to focus.

Air passages such as your trachea (windpipe), which may contain air your body can't use, are known as: 1: Brachia. 2: Bronchials. 3: Dead air spaces. 4: Restricted orifices.

Dead air spaces.

Dive planning elements may include all of the following except: 1: Purpose of dive. 2: Notifying a third party of your plans. 3: Reviewing hand signals. 4: Deciding whose computer to follow.

Deciding whose computer to follow.

Steps in equipment assembly include all of the following except: 1: Check cylinder and O-ring. 2: Attach BC and regulator. 3: Depressurize system and test regulators. 4: Clip off alternate-air-source second stage and instrument console.

Depressurize system and test regulators.

What should you do if you suddenly feel ill and/or develop a headache during a scuba dive? 1: Consult a physician as soon as possible. 2: End the dive and make a normal, slow ascent. 3: Ascend to a depth where the symptoms dissipate. 4: Both the first and third answers are correct.

End the dive and make a normal, slow ascent.

Any time a regulator is out of your mouth under water, you should: 1: Hold your breath to conserve your remaining air. 2: Exhale a small, steady stream of bubbles. 3: Exhale forcefully to purge your lungs of air. 4: None of the above.

Exhale a small, steady stream of bubbles.

Contact lens wearers should not close their eyes when clearing a mask. 1: True 2: False

False

It is substantially harder to remove and replace the weight pockets in a BC than it is to remove and replace a conventional weight belt. 1: True. 2: False.

False

Psoriacysts produce toxins that, when touched, can produce symptoms ranging from a mild rash or sting to anaphylactic shock or even paralysis. 1: True. 2: False.

False.

How much faster does sound travel in water, compared to air? 1: Twice as fast. 2: Four times as fast. 3: Over 200 times as fast. 4: Over 800 times as fast.

Four times as fast.

Scuba cylinders must be: 1: Hydrostatically tested every four years and visually inspected every six months. 2: Hydrostatically tested and visually inspected at intervals determined by local laws and regulations, or prevailing standards of practice. 3: Hydrostatically tested every year and visually inspected every five years. 4: None of the above.

Hydrostatically tested and visually inspected at intervals determined by local laws and regulations, or prevailing standards of practice.

What should you and your buddy do if separated during a dive? 1: Continue alone to your pre-agreed exit point. 2: Look for a new dive buddy. 3: Immediately start their prearranged plan for finding each other. 4: Search for no more than three minutes, then continue alone.

Immediately start their prearranged plan for finding each other.

The backward roll: 1: Is less disorienting than a giant stride. 2: Works best in colder water. 3: Is chiefly a small-boat entry. 4: Cannot be used in salt water.

Is chiefly a small-boat entry.

Which of the following is not true? 1: Longshore currents always move in the same direction. 2: Wind, waves and tides are among the factors that can affect the direction of longshore currents. 3: Longshore currents frequently move in the same direction as permanent offshore currents. 4: Local dive operators are a good source of information on the behavior of longshore currents.

Longshore currents always move in the same direction.

You will generally get the longest bottom times by: 1: Making the shallowest dives first. 2: Making the deepest dives first. 3: Waiting no more than 90 minutes between dives. 4: Doing no more than two dives a day.

Making the deepest dives first.

Which 'if any' of the following are true? 1: Aquatic animals present a greater risk to divers than any other factor. 2: Most aquatic animal bites result from an animal's defensive response to a perceived threat or, on rare occasions, from a case of mistaken identify. 3: Because they are perceived as more aggressive, men are more likely to be the victim of an aquatic animal attack than women are. 4: None of the above.

Most aquatic animal bites result from an animal's defensive response to a perceived threat or, on rare occasions, from a case of mistaken identify.

The most commonly used method of finding your way under water is: 1: Natural navigation. 2: Computer navigation. 3: Compass navigation. 4: None of the above.

Natural navigation.

As you descend: 1: Colors will remain largely the same. 2: Blues and grays disappear quickly. 3: Dive lights have little effect on apparent color. 4: None of the above.

None of the above.

In general, you want to enter the water with your BC: 1: Deflated. 2: Partially inflated. 3: Fully inflated. 4: Both the first and third answers are acceptable; the second answer is not.

Partially inflated.

Risk management is defined as: 1: Eliminating any possibility of a diving accident. 2: Preventing problems while at the same time having a planned response for any emergency. 3: Having the right kind of insurance. 4: Both the first and third answers are correct.

Preventing problems while at the same time having a planned response for any emergency.

Having just enough weight to achieve all three states of buoyancy with only minor adjustments in the water is the definition of: 1: Breath control. 2: BC use. 3: Proper weighting. 4: None of the above.

Proper weighting.

The two most common methods for recovering a regulator that has fallen behind your shoulder are: 1: Reach, Blast 2: Sweep, Purge 3: Reach, Sweep 4: Sweep, Blast

Reach, Sweep

Which of the following is the most effective means of preventing a leg cramp from returning? 1: Remove the fin from the affected leg and kick using just the remaining fin. 2: Slow down and switch to a different style of kick. 3: Swim with just your hands. 4: 1 or 3, but not 2

Slow down and switch to a different style of kick.

________ _________ has a detrimental effect on diving. 1: Regular exercise 2: Smoking cigarettes 3: Impaired vision 4: None of the above

Smoking cigarettes.

At the first sign of overexertion: 1: Abort the dive. 2: Stop, relax and breathe deeply. 3: Signal to the shore or boat for assistance. 4: Both the first and third answers are correct.

Stop, relax and breathe deeply.

Under water, the easiest way to remove and replace a scuba unit is to: 1: Pass it over your head. 2: Take it off and put it on like a jacket. 3: Stand on it. 4: None of the above.

Take it on and off like a jacket.

Additional features common to many dive computers include all of the following except: 1: The ability to display dive log data and to upload that data to a laptop or desktop computer. 2: The ability to monitor a diver's exposure to air, Nitrox and Trimix. 3: The ability to project no-decompression limits for upcoming dives. 4: Bar graphs that provide a visual representation of a diver's exposure to nitrogen and other gasses.

The ability to monitor a diver's exposure to air, Nitrox and Trimix.

The chief cause of nitrogen narcosis is: 1: Diving past 40 m/132 ft. 2: The elevated partial pressure of nitrogen divers experience at depth. 3: The combination of carbon dioxide and nitrogen at depth. 4: None of the above.

The elevated partial pressure of nitrogen divers experience at depth.

Which member of the buddy team determines the pace for the dive? 1: It doesn't matter, so long as both buddies agree. 2: The stronger buddy. 3: The weaker buddy. 4: None of the above.

The weaker buddy.

When water stratifies itself into layers, according to temperature, the boundary between layers is known as a(n):1: Halocline. 2: Ichtyocline. 3: Thermodyne. 4: Thermocline.

Thermocline.

A wave encountering shallow water begins to slow at it bottom, while the top of the wave continues at its previous speed. This causes the wave to break. 1: True. 2: False.

True

Without proper training, all you may accomplish by searching for a missing buddy on your own is to put yourself at risk. 1: True. 2: False.

True

The volume of gas in a flexible container at a depth of 10 m/33 ft will expand to ______ its original volume if taken to the surface. 1: Twice. 2: Three times. 3: Four times. 4: None of the above.

Twice

Which of the following is/are true? 1: Water conducts heat away from your body ten times faster than air does. 2: Water conducts heat away from your body 25 times faster than air does. 3: Fresh water conducts heat away from your body faster than salt water does. 4: Salt water conducts heat away from your body faster than fresh water does.

Water conducts heat away from your body 25 times faster than air does.

Which of the following statements is not true? 1: Wet suits work by surrounding your body with a low-density material (neoprene) foam, that retards heat loss through radiation. 2: To work, a wet suit must fit snugly to reduce the amount of cold water that circulates through the suit. 3: Wet suits are unnecessary in water warmer than 25 °C/77 °F. 4: Dive skins help protect you from scrapes, abrasion and sunburn; however, they offer little in the way of insulation.

Wet suits are unnecessary in water warmer than 25 °C/77 °F.

To minimize the risk of a lung overpressure injury during an independent emergency ascent: 1: You must exhale completely prior to beginning your ascent. 2: You must make at least three attempts at inhaling during your ascent. 3: You must be exhaling continuously any time you cannot inhale. 4: You must spit out your regulator at the beginning of the ascent.

You must be exhaling continuously anytime you cannot inhale.

We measure waves by their height and weight. 1: True. 2: False.

false.

Depending on circumstances, there are times when divers may wish to be positively, negatively or neutrally buoyant. 1: True. 2: False.

true