Scuba

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The key to using air efficiently while breathing from scuba is to: A. Breathe slowly and deeply. B. Briefly hold your breath between inhalations. C. Breathe rapidly, taking only shallow breaths. D. None of the above.

A. Breathe slowly and deeply.

Which of the following is among the most effective means of relieving a leg cramp once it has occurred? A. Grasp the fin tip of the affected leg and pull towards you while straightening the leg. This stretches the calf muscle. B. Change to a different style of kick. C. Have a buddy tow you back to the boat or shore. D. None of the above.

A. Grasp the fin tip of the affected leg and pull towards you while straightening the leg. This stretches the calf muscle.

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

A. Longshore currents always move in the same direction.

The most commonly used method of finding your way under water is: A. Natural navigation. B. Computer navigation. C. Compass navigation. D. None of the above.

A. Natural navigation.

Which of the following is not true? When Clearing a mask, you should: A. Pull out slightly at the base of the mask to create a space for water to exit. B. Inhale through your mouth, but exhale through your nose. C. Take as many breaths as needed to clear the mask completely. D. Look up during the last exhalation to make the bottom of the mask skirt the lowest point.

A. Pull out slightly at the base of the mask to create a space for water to exit.

All of the following are true except: A. You can help prevent mask squeeze by exhaling periodically into your mask during ascent. B. Regular dental care and ensuring your teeth are free of gas spaces can help prevent tooth squeeze. C. If you experience a reverse block, descend to a point where the pain subsides, then ascend slowly while wiggling your jaw and swallowing. Repeat this process as needed until you can ascend without pain or discomfort. D. The danger in taking decongestants is that they may wear off during a dive and have other possible side effects.

A. You can help prevent mask squeeze by exhaling periodically into your mask during ascent.

A scuba cylinder that normally lasts one hour at the surface will last _______ minutes at 20 m/66 ft. A. 30 B. 20 C. 15 D.10

B. 20

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

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

Which of the following is the best way to prevent or reduce nitrogen narcosis? A. Avoid unnecessary exertion, as elevated carbon dioxide levels exacerbate narcosis. B. Avoid dives below 20 m/66 ft. C. Use a dry suit, as cold increases the risk of narcosis. D. Both the first and third answers are correct.

B. Avoid dives below 20 m/66 ft.

Some alternate air sources are combined with a _________ , to reduce the number of hoses connected to the first stage regulator. A. Tire inflator B. BC power inflator C. Snorkel D. Submersible pressure gauge

B. BC power inflator

To be injured by an animal with poisonous spines, you must: A. Be within a radius of 3 m/10 ft, as most poisonous animals cannot shoot their spines farther than this. B. Be the aggressor and touch the animal first. C. Be barehanded, as most spines cannot pass through gloves. D. None of the above.

B. Be the aggressor and touch the animal first.

Common BC components include all of the following except: A. Harness. B. CO2 inflation mechanism. C. Air cell. D. Inflation/deflation mechanism.

B. CO2 inflation mechanism.

Which of the following is not true? A. Entering shallow water causes the base of a wave to slow. B. Entering shallow water forces wave energy upward, making the wave crest unstable and causing it to break. C. If the top of a wave moves faster than the bottom, the wave will tend to break. D. Both the first and third answers are true.

B. Entering shallow water forces wave energy upward, making the wave crest unstable and causing it to break.

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

B. Exhale a small, steady stream of bubbles.

Any time you cannot inhale while scuba diving (such as when a regulator is out of your mouth), you must be: A. Holding your breath to conserve your remain- ing air. B. Exhaling. C. Monitoring your depth to avoid accidental ascents while breath holding. D. Both the first and third answers are correct.

B. Exhaling.

Key points in recovering a second stage using the sweep method include: A. Using your left hand to push up on the bottom of your cylinder. B. Leaning forward, dipping your right shoulder. C. Leaning forward, dipping your left shoulder. D. None of the above.

B. Leaning forward, dipping your right shoulder.

On most repetitive dives, your computer will provide _______ no deco limits than on single dives. A. Less conservative B. More conservative C. Significantly greater D. None of the above

B. More conservative

Which (if any) of the following are true? A. Aquatic animals present a greater risk to divers than any other factor. B. 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. C. Because they are perceived as more aggres- sive, men are more likely to be the victim of an aquatic animal attack than women are. D. None of the above.

B. 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.

_________________ has an understandably detrimental effect on diving. A. Regular exercise B. Smoking cigarettes C. Impaired vision D. None of the above

B. Smoking cigarettes

If possible, before attaching your BC to your scuba cylinder, you should: A. Inflate it completely. B. Soak the cam band (tank band) in water. C. Attach the regulator to the cylinder first. D. Connect the BC low pressure inflator hose to the BC.

B. Soak the cam band (tank band) in water.

Which of the following is/are true? A. Surge is the backwash of water from waves breaking on shore. B. Surge is the back and forth movement of water caused by waves passing over head. C. Surge occurs when waves force water between facing rock ledges. D. None of the above.

B. Surge is the back and forth movement of water caused by waves passing over head.

Among the key points in using your BC to help maintain neutral buoyancy under water: A. Add or remove air to or from your BC only in large bursts, until you develop a more intuitive feel for the process. B. To be successful in maintaining neutral buoyancy, you must be: aware of changes in depth, and, anticipate the need to add or vent air from your BC by keeping a hand on the inflator. C. Before you can achieve neutral buoyancy, you must first assume a finpivot position on the bottom. D. None of the above.

B. To be successful in maintaining neutral buoyancy, you must be: aware of changes in depth, and, anticipate the need to add or vent air from your BC by keeping a hand on the inflator.

Which of the following is/are true? A. Water conducts heat away from your body ten times faster than air does. B. Water conducts heat away from your body 25 times faster than air does. C. Fresh water conducts heat away from your body faster than salt water does. D. Salt water conducts heat away from your body faster than fresh water does

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

The most accurate place to conduct a weight check is: A. At the surface, at the beginning of the dive. B. At the deepest point reached during the dive. C. At safety stop depth, at the end of the dive. D. None of the above.

C. At safety stop depth, at the end of the dive.

All of the following can help prevent decompression sickness (DCS) except: A. Make a safety stop of between three and five minutes at a depth of 3 to 6 m/10 to 20 ft. B. Remain well within your dive computer's no decompression limit. C. Avoid drinking fluids prior to the dive. D. Ascend no faster than the rate allowed by the dive computer.

C. Avoid drinking fluids prior to the dive.

Objects under water appear: A. The same size as they do on land. B. Twice as large as they do on land. C. Closer and larger than they do on land. D. Smaller and farther away than they do on land.

C. Closer and larger than they do on land.

Which type of alternate air source does not necessarily require the donor to give up his primary second stage? A. Technical diving configuration. B. Alternate air source inflator. C. Conventional alternate air source second stage. D. None of the above.

C. Conventional alternate air source second stage.

The presence of thermoclines means that: A. Surface temperatures will provide divers with a good indication of what they can expect at depth. B. Divers may require less in the way of exposure protection at depth than they will at the sur- face. C. Divers may require more in the way of expo- sure protection at depth than they will at the surface. D. None of the above.

C. Divers may require more in the way of expo- sure protection at depth than they will at the surface.

If you will be rinsing your regulator after removing it from the cylinder, you must make sure that the ____________ is firmly in place. A. Mouthpiece plug B. Alternate air source retainer C. Dust cap D. None of the above

C. Dust cap

The first rule in handling any problem situation at the surface is to: A. Signal for help. B. Ditch your scuba unit. C. Establish positive buoyancy. D. None of the above.

C. Establish positive buoyancy.

Which of the following is/are true? A. If caught in a rip current, swim directly towards shore, using the most powerful kick possible. B. If caught in a rip current, swim perpendicular to shore, until you are completely out of the rip current, then swim in towards shore. C. If caught in a rip current, swim parallel to shore, until you are completely out of the rip current, then swim in towards shore. D. Don't fight the rip current relax and let it carry you closer to shore.

C. If caught in a rip current, swim parallel to shore, until you are completely out of the rip current, then swim in towards shore.

What should you and your buddy do if separated during a dive? A. Continue alone to your preagreed exit point. B. Look for a new dive buddy. C. Immediately start their prearranged plan for finding each other. D. Search for no more than three minutes, then continue alone.

C. Immediately start their prearranged plan for finding each other.

If you cannot reunite with a missing buddy: A. Initiate an underwater search, using an expanding square pattern. B. Seek assistance from the closest military base. C. Leave underwater searches to trained professionals. D. None of the above.

C. Leave underwater searches to trained professionals.

If your buoyancy is under control, you should be able to hover at any time by: A. Adding just a single puff of air to your BC. B. Inhaling deeply. C. Not kicking or moving. D. Both the first and second answers are correct.

C. Not kicking or moving.

_________ buoyant items tend to float__________ buoyant items tend to sink, items that are __________ buoyant neither float nor sink. A. Negatively, neutrally, positively B. Positively, neutrally, negatively C. Positively, negatively, neutrally D. None of the above.

C. Positively, negatively, neutrally

After your buddy checks to see that your air is turned all the way on: A. You are ready to enter. B. Reach back and double check it yourself. C. Take several deep breaths from your regulator while watching your SPG for changes in pressure. D. None of the above.

C. Take several deep breaths from your regulator while watching your SPG for changes in pressure.

During an independent emergency ascent, you should stop periodically and attempt to inhale through your regulator because: A. Doing so reduces the risk of decompression sickness B. Doing so reduces the risk of lung overpressure injuries. C. The decreasing pressure may allow your regulator to function, even if it could not do so at depth. D. The air in your cylinder will expand on ascent, allowing you to breathe.

C. The decreasing pressure may allow your regulator to function, even if it could not do so at depth.

Which of the following is/are true? A. Tides seldom have a significant impact on depth or dive plans. B. Strong tidal currents frequently bring clearer water with them. C. Tidal currents can be very strong, making diving difficult or even dangerous. D. None of the above.

C. Tidal currents can be very strong, making diving difficult or even dangerous.

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

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

All of the following true except: A. Gloves can provide protection from both cold and abrasion. B. It's not a bad idea to carry a pair of lightweight gloves in your BC pocket for unforeseen contingencies, even if you normally dive barehanded. C. You don't need to wear wet suit gloves to protect against cold until the water temperature drops below 10 °C/50 °F. D. Some dive destinations actually prohibit the use of gloves, as some divers who use them are less careful about touching fragile coral polyps.

C. You don't need to wear wet suit gloves to protect against cold until the water temperature drops below 10 °C/50 °F.

"Any diver can signal to ______ the dive for any ________." A. shorten, reason B. continue, buddy C. abort, reason D. abort, buddy

C. abort, reason

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

D. All of the above.

Always dive within the limits of your: A. Training. B. Equipment. C. Experience. D. All of the above.

D. All of the above.

Among the reasons divers prefer computers over dive tables: A. Computers account for the multilevel nature of most dives and, therefore, allow longer no decompression limits. B. Computers are generally more convenient to use than dive tables. C. Computers provide among the best possible means of keeping ascent rates under control. D. All of the above.

D. All of the above.

Contributing factors to decompression sickness can include: A. Rapid ascents. B. "Pushing" or exceeding your computer's no decompression limits. C. Heavy exertion and/or dehydration. D. All of the above.

D. All of the above.

If you are unable to make a required decompression stop: A. Breathe pure oxygen for at least 30 minutes. B. Monitor for signs and symptoms of decompression sickness for the next 24 hours. C. Do not dive or fly for at least 24 hours. D. All of the above.

D. All of the above.

Rinsing equipment in fresh water helps remove: A. Salt. B. Chlorine. C. Sand, mud and other sediments. D. All of the above.

D. All of the above.

Which of the following may indicate that air in a scuba cylinder is contaminated and potentially toxic? A. Color. B. Odor. C. Taste. D. Any of the above.

D. Any of the above.

A mask must cover the nose: A. To prevent water from entering. B. To ensure the best possible fit. C. So that you can keep the pressure inside the mask equal to the pressure outside. D. Both the first and second answers are correct.

D. Both the first and second answers are correct.

Common weight systems include: A. Weight belts. B. BCs with integrated weight systems. C. Cylinders with weights permanently affixed to the boot. D. Both the first and second answers are correct.

D. Both the first and second answers are correct.

Which of the following statements are true? A. Wave height is the distance from its highest point (crest) to its lowest point (trough). B. Wave length is the distance from crest to crest. C. Wave oscillation to calculated by multiplying the wave height times its length. D. Both the first and second answers are correct.

D. Both the first and second answers are correct.

You can help prevent seasickness by: A. Staring at the horizon. B. Avoiding diesel fumes and other strong odors. C. Eating a large meal prior to departure. D. Both the first and second answers are correct.

D. Both the first and second answers are correct.

Among the key points in doing a flutter kick: A. Keep your knees as straight as possible. B. Emulate the leg movements you make when pedaling a bicycle. C. Key your toes pointed. D. Both the first and third answers are correct.