Download PADI Open Water Exam Study Guide With 100% Complete Solution 2025/2026 and more Exams Advanced Education in PDF only on Docsity!
PADI Open Water Exam Study Guide
With 100% Complete Solution 2025/
When is an object positively buoyant? - Correct Answer-When it displaces a volume of water weighing more than its own weight. When is an object negatively buoyant? - Correct Answer-When it displaces a volume of water weighing less than its own weight. When is an object neutrally buoyant? - Correct Answer-When it displaces a volume of water weighing the same as its own weight. Why two pieces of equipment do you use to control your buoyancy? - Correct Answer- BCD, Lead weight What does buoyancy help with when you are underwater? - Correct Answer-Controlling where you are What does buoyancy help with when you are at the surface? - Correct Answer- Floatation, conserving energy How does the buoyancy of an object differ in fresh/salt water? - Correct Answer-More buoyant in salt than fresh When you exhale what happens? - Correct Answer-Lung volume decreases so you have less buoyancy. When you inhale what happens? - Correct Answer-Lung volume increases so you have more buoyancy. Why don't you feel air pressure? - Correct Answer-Your body is primarily liquid, which is incompressible and distribute pressure equally throughout your whole body. Where are some air spaces located in the body? - Correct Answer-Ears, sinuses, lungs Do you always feel the pressure in body air spaces? - Correct Answer-Only if the pressure is different inside and outside the air spaces. 1 bar is what depth? - Correct Answer-0m/0ft 2 bar is what depth? - Correct Answer-33ft/10m 3 bar is what depth? - Correct Answer-66ft/20m
4 bar is what depth? - Correct Answer-99ft/30m How is air volume affected when depth is increased? - Correct Answer-It decreases How is air density affected when depth is increased? - Correct Answer-It increases What happens if you take an air volume underwater with you in a flexible container or inverted jar? - Correct Answer-As pressure increases the volume decreases, same air but smaller space. How do you maintain air volume as you descend? - Correct Answer-Equalize What is a "squeeze"? - Correct Answer-As volume decreases, pressure pushes body tissues inwards toward air space, causing discomfort. Pressure outside air space is more than pressure inside air space. Where can you get a squeeze? - Correct Answer-Ears, sinuses, mask, lungs, teeth How do you equalise air spaces in ears? - Correct Answer-Blow and squeeze nose, wiggle jaw, swallowing How often should you equalise? - Correct Answer-Every metre before discomfort What do you do if you feel discomfort? - Correct Answer-Ascend until discomfort eases, equalise, continue descent slowly Why can't you scuba while sick? - Correct Answer-Congestion can plug air passages so you can't equalize What is mask equalisation? - Correct Answer-exhale into mask by nose What does your nose need to be in the mask? - Correct Answer-To equalize First rule of diving - Correct Answer-Always breathe continuously What happens if you hold your breath during ascent? - Correct Answer-Lung over expansion, forces air into bloodstream and chest cavity, leading to paralysis or death. What is a reverse block? - Correct Answer-When air cannot escape from a air space during ascent How do you react to reverse block? - Correct Answer-Slow/stop ascent and give air time to work its way out As you go deeper you use your air ___? - Correct Answer-faster
What is DIN valve - Correct Answer-Screw regulator into valve What is the O-ring - Correct Answer-Located in valve, when cylinder and regulator connect forms air tight seal (O-ring) What are cylinders made of - Correct Answer-Aluminum and steel How often should the cylinder be inspected - Correct Answer-At least once a year What are hydrostatic tests? - Correct Answer-Tests expansion of cylinder in high pressure environment What is the normal full pressure of a scuba tank? - Correct Answer-200 bar Parts of regulator - Correct Answer-First stage Second stages Dust cover Purge Button What is first stage? - Correct Answer-Connect A regular redues high pressure cylinder air is ___ steps? - Correct Answer- Second stage? - Correct Answer-Breathing source Paul's second rule - Correct Answer-Always dive with a buddy Paul's third rule - Correct Answer-Slowly ascent from all dives Paul's 4th rule - Correct Answer-Have fun How often does regulator be tested? - Correct Answer-Annually When you rinse the regulator don't.. - Correct Answer-Press purge, no dust cap SPG shows: - Correct Answer-How much air you have during dive As you descend colors go from... - Correct Answer-Red -- blue Sound travels father in __ than in ___ - Correct Answer-water, air Sounds travels __ times faster in water than air - Correct Answer- Water conducts heat about __ times faster than air does - Correct Answer-
Hypothermia - Correct Answer-body cools so much it can't function When you're underwater things appear - Correct Answer-larger and closer Water absorbs light so... - Correct Answer-it gets darker when you go deeper and colors become less vivid Underwater, sounds seem to come from ... - Correct Answer-overhead When you shiver - Correct Answer-Get out of water and dry off and seek warmth Symptoms of overexertion include - Correct Answer-rapid breathing anxiety a feeling of suffocation To prevent overexertion: - Correct Answer-pace yourself, know your limits, avoid prolonged heavy exertion If you become overexerted - Correct Answer-stop all activity and rest 75% heat loss in body occurs in - Correct Answer-head Important part of weight system is the - Correct Answer-right hand release If you're properly weighed you will - Correct Answer-float at eye level with an empty BCD and holding a normal breath Low pressure inflator allows for - Correct Answer-inflation/deflation of BCD How to check your buddy - Correct Answer-Begin With Review And Friend Where do you attach alternate air source? - Correct Answer-Within the triangle Underwater conditions that affect a diver include" - Correct Answer-sunlight temperature water movement bottom composition What is a thermocline? - Correct Answer-A gradual change to a layer of colder water? Factors that affect visibility are - Correct Answer-water movement, weather, suspended particles, bottom composition Underwater Visibility is: - Correct Answer-the approximate distance you can see horizontally
Before diving, don't - Correct Answer-drink excessively the night before You can prevent and control most surface problems by - Correct Answer-establish positive buoyancy, dive within your limits, relax when you dive Panicked divers typically: - Correct Answer-push off their masks, spit their regulators, need immediate help How do you react to running low on or out of air? - Correct Answer-1. Make a normal ascent
- Ascend with an alternate air source
- Ascend using a controlled emergency swimming ascent
- Buoyant emergency ascent Uses for a dive float include - Correct Answer-Assisting another diver resting supporting a dive flag carrying accessories You should use a dive flag because - Correct Answer-it warns off boaters local law may require it The rule of thumb is that you should stay within ___ of your dive flag, and boaters should stay ___ away. - Correct Answer-15 metres, 30-60 metres Collecting bags are useful for - Correct Answer-collecting under water garbage carrying several objects are once Underwater lights are taken down on day dives because they - Correct Answer-restore lost colors, are used to look in cracks and crevices Carry a slate with you in order to communicate, carry info. T/F - Correct Answer-True Air is made up of - Correct Answer-nitrogen and oxygen Symptoms of contaminated air include - Correct Answer-headache, nausea, cherry red lips/nail beds If a diver has contaminated air you should - Correct Answer-give the diver fresh air, give the diver oxygen, reach medical attention Symptoms of nitrogen narcosis include - Correct Answer-false sense of security, foolish behavior, anxiety If nitrogen narcosis occurs - Correct Answer-ascend to a shallower depth
To prevent narcosis - Correct Answer-don't go on deep dives Two factors influencing how much nitrogen you absorb include - Correct Answer-dive time and depth Secondary factors that influence nitrogen absorption include - Correct Answer-alcohol consumption, dehydration, age, being overweight Symptoms of decompression sickness - Correct Answer-limb and joint pain mild tingling and fatigue paralysis and unconsciousness ' Decompression illness implies - Correct Answer-both decompression sickness and lung over expansion injuries If you have decompression illness you should - Correct Answer-have emergency oxygen lie on left side if unresponsive contact local emergency medical care contact local diver emergency service Why do you take safety stops - Correct Answer-To give your body time to eliminate nitrogen, to allow you to stabilise and control your ascent The recommended general depth and time for a safety stop is: - Correct Answer- metres for 3 minutes Safety stop is required when - Correct Answer-you dive to 30 metres or deeper you reach the limit on your table your dive comes within three pressure groups of an NDL on the RDP If you exceed your no decompression limit by less than 5 minutes you should - Correct Answer-ascend to 5 meters, wait 8 minutes, don't dive for 6 hours If you exceed your no decompression limit by more than five minutes you should - Correct Answer-ascend to 5 metres, wait 15 minutes, don't dive for 24 hours If you exceed the no decompression limit of your dive computer you should - Correct Answer-make an emergency decompression stop You should plan your dive __ metres ___ in cold conditions - Correct Answer-4m deeper Parts of compass - Correct Answer-index marks magnetic north needle
