Scuba Diver (Digital Versión)

International Scuba Diving Training Organization SCUBA DIVER (DIGITAL VERSIÓN)

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This manual is intellectual property of ACUC. Its reproduction by any method is forbidden without written consent from the ACUC European office

Ask your Instructor to show you his/her ACUC Certification Card and ensure is in “Active” Status. See the “Consumer Info” section in the ACUC web www.acuc.es

Press here to continue INDEX

Introduction 5

1. Selecting the basic equipment (snorkelling equipment) 6

2. Putting on the basic equipment 8

3. Using the basic equipment 9

4. Selecting the scuba equipment 12

5. Wearing the scuba equipment 16

6. Diving Physiology 19

7. Using the scuba equipment 23

8. Emergency ascent 27

9. Underwater communications 29

10. Decompression and different dive types 31

11. Rescue and first aid 33

12. The marine environment 34

13 ACUC International 36

Press here to go to first chapter Author: Juan Rodriguez

Thank you to: CRESSI-SUB (Spain), UWATEC (Spain) and Mario Bofill, ACUC Instructor Trainer Evaluator .

Illustrations: Corel Draw Corporation; Ismael Molina; Jose Carrasco; Manuel Sanchez and Bernat Comellas

Press here to start Inicio SCUBA DIVER

Introduction INTRODUCTION 1. Selecting the basic equipment IMPORTANT

2. Putting on the basic This handbook is not a text book. Its purpose is to emphasize the most important points equipment that the candidate must remember. The Instructor will expand on each topic with his explanations and demonstrations both in the class and pool. If the student wishes a more 3. Using the basic in‑depth text book, please request the ACUC Open Water Manual from your Instructor, equipment dive store, or the closest office of ACUC.

4. Selecting the scuba ACUC wishes to thank the many Instructors whose input was most valuable in putting this equipment set of notes together. Many hours were spent by Juan Rodriguez in writing the basic notes. We would be remiss if we did not mention Norman Hughes, Ann‑Marie Hughes, Herb Holst, Art Penny, Mary Maguire, Bill Mason and Paul Melanson who spent many hours 5. Wearing the scuba checking the accuracy, helping to put the text in order and making the notes relevant in equipment today's diving.

6. Diving physiology The ACUC Scuba Diver course is an optional course (except in those countries where this course is, due to the legislation of the country, obligatory). Its situation in the ACUC training ladder, at a technical and abilities level, is above a course of Introduction to Diving 7. Using the scuba and below the course of Open Water Diver. This course can be offered by any ACUC equipment Assistant Instructor or higher level and it can be certified by any ACUC Entry Level Instructor or higher level. 8. Emergency ascents The main characteristics of this course are that the students that pass the course, will not be able to dive if it is not under the direct supervision of as a minimum, an ACUC 9. Underwater Divemaster or similar level of other organizations recognised by ACUC. Also, the communications maximum diving depth for this level is 15 meters (50 feet).

10. Decompression and The maintenance on the part of the diver of a dive log book is important for this level. The different dive types diver must ensure to register all his dives in the log book and that these dives are signed by the Divemaster leading the dive and stamped by the Dive Center.

11. Rescue and first aid

12. The marine environment

13. ACUC International

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Page 6 Introduction ACUC - SCUBA DIVER

1. Selecting the basic 1. SELECTING THE BASIC EQUIPMENT (SNORKELING EQUIPMENT) equipment 1.1 TERMINOLOGY 2. Putting on the basic equipment It is important that you know something of the terminology applied to diving. For example: The equipment used in diving is referred to as SCUBA (Self Contained Underwater Breathing Apparatus). "SNORKEL" is diving using only 3. Using the basic basic equipment. equipment

4. Selecting the scuba 1.2 TYPES OF MATERIALS equipment Basic equipment is manufactured mainly of Rubber, Black Silicone and / or 5. Wearing the scuba Clear Silicone. Never mix equipment made of Clear Silicone with rubber equipment. This will cause stains in the silicone. equipment

6. Diving physiology 1.3 FINS Open fin

The two most common types of fins used in diving today are: Full Foot and 7. Using the scuba Adjustable. The full foot type is better for warm waters, allows thin sole boots equipment to be worn and is recommended for Snorkeling. The adjustable type is for colder waters or when thicker boots are worn. The straps should be easy to manage. These fins are recommended for diving with SCUBA. Long bladed 8. Emergency ascents fins are recommended Snorkeling and broad bladed fins for diving with SCUBA. The buoyancy of the fins can be positive, neutral (preferable) or negative. 9. Underwater communications 1.4 MASK 10. Decompression and It is important that you have a good double seal on the mask. Your Instructor different dive types will show you how to check the seal. The internal volume of the mask can be large, average or small (preferable for snorkeling). The glass should be 11. Rescue and first aid tempered. The mask strap should be split at the back and should be easily adjusted. The mask should be large enough to cover your eyes and nose. The reason for this will be evident later.

12. The marine environment 1.5 SNORKEL Masks

13. ACUC International It should be large bore, with a flexible mouthpiece, and a smooth bore inside that will not retain water, not too long and with soft curves. It should always be carried on the left side of the head to avoid interference with the regulator which comes over the right shoulder.

1.6 WEIGHT BELT

A belt is necessary to hold the weights. Normally, the body floats due to its internal air spaces and also from any thermal protection that is worn. The belt must have a quick release buckle that can be opened easily with one gloved hand. A belt is indispensable at shallow depths but it can have disastrous results if used in snorkel dives, without a protective suit, at depths greater than 10 meters (33 ft.) due to the volume decrease from pressure.

1.7 GLOVES AND BOOTS

For temperate waters, the gloves should be light but resistant to tearing and should some type of tracing on the palm to avoid objects from slipping. For cold water, the gloves should be of the same thickness as the protective suit. For very cold waters it is recommended the gloves be 3 fingered since they The snorkel are warmer but they offer less dexterity. The boots are necessary in cold water and when adjustable strap fins are worn, to avoid rubbing on the feet.

Page 7 ACUC - SCUBA DIVER

1. Selecting the basic equipment—snorkeling equipment (continued) 1.8 KNIFE

A knife is not a weapon, but a tool. Its construction should be of stainless steel. It is advisable that the tip of the knife be a screwdriver type and the handle have a flattened end usable as a hammer. At least one side must have saw teeth. It is recommended that the knife handle be brightly coloured since it will be easier to locate if lost. The sheath should have a double locking device. The knife can also be secured to the sheath with a coiled telephone cord. This will enable the wearer to have free movement to use it, avoid snagging on obstructions, but will prevent the knife from being lost if the sheath locking device fails.

1.9 DIVE BAG Weight belts

A dive bag should be strong and wide, with good ventilation. It should have different compartments, with at least one compartment quilted for carrying delicate instruments. Plastic zippers are recommended Buy a bag that is bigger than you think you will need. Divers always acquire more equipment and purchasing a larger bag in the beginning will avoid the expense of replacing the bag too soon.

Gloves for normal temperature water

Dive knife

Dive bags

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Page 8 Introduction ACUC - SCUBA DIVER

1. Selecting the basic 2. PUTTING ON THE BASIC EQUIPMENT equipment 2.1 BOOTS 2. Putting on the basic equipment Wet your foot and the boot before putting on if possible. Work your foot into the boot by wiggling your foot forward as you grasp the top of the boot and pull. Try to grasp the boot as far away from the edge as possible to avoid 3. Using the basic tearing the boot. equipment

4. Selecting the scuba 2.2 FINS equipment For fins with adjustable straps, they should be wetted first. Separate the strap 5. Wearing the scuba from the pocket of the fin, pushing the strap downward. Slide the foot into the pocket of the fin and pull the strap over the heel. Snug the strap up since with equipment the increase in pressure during the dive, the volume of the boot will decrease and the strap could get loose. Fold the heel of the full foot fin underneath, then once your foot has been slipped into the pocket, flip the heel of the fin up over 6. Diving physiology the heel of your foot.

7. Using the scuba equipment 2.3 KNIFE

The knife should be carried, depending on its size, in a place on the body 8. Emergency ascents where it does not obstruct swimming, but is within easy reach. For small size knives, it is suggested that it be carried on the BC strap or regulator hose other than that of the second stage. For large knives, either on the inside or 9. Underwater the outside of the leg, at mid calf. In either case, the straps should not be very communications loose, since, with the increase in pressure, the volume of the suit will decrease and the straps could get loose.

10. Decompression and different dive types 2.4 MASK

11. Rescue and first aid The face of the mask should be coated, before getting it wet, with an antifogging solution. (special liquids, potato, tobacco, saliva, etc.) The mask should then be wetted and rinsed. Wetting the mask before any of these solutions are applied will reduce their effectiveness. To wear the mask, raise 12. The marine environment the strap above the mask and place the mask on the face, holding it with one Trying the mask on hand. With the other hand, lower the holding strap until it is situated at the back of the head. Be sure that the straps are not crossed. Be sure that there is 13. ACUC International no hair between the front of the mask and the face, or that the mask is not covering the hood, since this would allow water to leak into the mask.

2.5 SNORKEL

The snorkel should be connected to the mask by a rubber or silicone ring (the same material as the mask) when snorkeling. The snorkel should be carried on the left side of the head, since the regulator hose will come from the right side. The mouthpiece of the snorkel should be positioned so that it is comfortable in your mouth.

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Page 9 Introduction ACUC - SCUBA DIVER

1. Selecting the basic 3. USING THE BASIC EQUIPMENT equipment 3.1 TWO COMMON FINNING STYLES 2. Putting on the basic equipment The most common fining styles are the Flutter kick and the Dolphin kick in case a fin is lost. Your Instructor will demonstrate them.

3. Using the basic equipment

4. Selecting the scuba equipment

5. Wearing the scuba equipment Flutter kick Dolphin kick

6. Diving physiology 3.2 TWO METHODS OF SNORKEL CLEARING 7. Using the scuba The Blast Method, blowing rapid and strong at the surface and the equipment Displacement Method, blowing gently and continuous before reaching the surface with the head tilted back.

8. Emergency ascents

3.3 EAR EQUALIZATION 9. Underwater communications It is very important to do this manoeuvre four or five times before submerging in order to check if your ears will clear before you get wet. Once in the water, the equalization manoeuvre is done at the start of the dive and then each few 10. Decompression and feet of depth until arriving at the desired depth. The equalization manoeuvre different dive types consists of blowing gently through the nose while pinching the nostrils closed (Valsalva Method). Make sure the air does not escape through the mouth. This equalization can also be done by swallowing. You may also try moving 11. Rescue and first aid the tongue to the top of the back of the mouth and trying to make a clucking sound. In the event of an earache, notify your buddy and ascend slowly until the ache goes away. Then clear and begin to descend again. The dive must 12. The marine environment be cancelled in the event of a cold or when the nasal sinuses are congested.

3.4 MASK EQUALIZATION 13. ACUC International The Valsalva method Exhale gently into the mask through the nose to equalize.

3.5 TWO TYPES OF SURFACE DIVES

 Feet First: With your body in a vertical position, bring your legs together quickly in a scissors style motion hard enough to push your body vertically upwards in the water. Allow your body to drop back down into the water and as your head submerges, sweep your arms upwards (with your palms facing up) above your head. Once you are completely submerged, rotate your body to a horizontal position and start fining.  Head First: In a horizontal position, looking down, with your arms parallel to your body, do the following two movements in rapid succession:  Bend at the waist 90° downward, extending your arms in front of your head.  Lift your legs (knees straight) out of the water so that the weight of your legs above the surface force your body downward. Bring your arms back parallel to your body.

Page 10 ACUC - SCUBA DIVER

3. Using the basic equipment (continued)

Clearing the mask

Feet first dive

3.6 THREE ENTRY TYPES

There are three main entry types into the water: Head first dive

 Stride: Check the entry area to ensure no one is in the way and there are no obstacles. In a standing position, look towards the horizon, hold your mask with one hand, control all gauges with the other hand and step out from the entry point as if stepping into space.  Controlled Seated: Sit on the edge of the entry point, check for persons or obstacles in the way. Place the hand closest to the direction you wish to enter (left or right) beside you facing towards the water. Place your other hand beside this one about 6 to 10 inches apart and facing opposite. Push with your hands lifting and turning your body 180° degrees towards where your hands are placed. Ease yourself into the water so that you are looking towards the entry point and moving your hand around so both hands are facing the same direction as your body.  Back Seated: check that the entry point is clear of people or obstacles. Sit with your back to the water and check once again for obstacles at the entry point by looking to the left and right. Hold your mask and regulator with one hand and control all gauges with the other. Tuck your chin into your chest and by pushing slightly with your legs, fall backwards with your legs positioned 90° to the body. Maintain this position until underwater.

3.7 DIVING WITHOUT A MASK BREATHING THROUGH THE SNORKEL

It is important to be able to do this in case of a lost mask. It should be learned and practiced often, breathing solely by the mouth, exhaling through the nose slowly and constantly. Your instructor will help you develop the ability. When snorkelling, energy is expended lifting the head out of the water to breath. By learning this skill, energy can be saved.

3.8 ARCHIMEDES PRINCIPLE: BUOYANCY CONTROL & SURFACE RESTING

Archimedes Principle states that any object wholly or partly immersed in a liquid is buoyed up by a force equal to the weight of the liquid displaced by the object. The lungs are similar to a buoyancy compensator if you know how to use them. To prove this you can do a simple exercise. In the deep end of the pool and breathing through the snorkel,, lay flat on the surface with your arms extended above your head, hands crossed and palms facing downward. Inhale fully and hold your breath for 10 seconds. After 10 seconds, begin to exhale the air. You will be able to see how, when the air starts to leave the lungs, you will begin to sink. Therefore, never exhale fully while on snorkel. Exhale only half what is inhaled.

3.9 CRAMPS

To ease cramps, the best technique is to stretch the affected leg forward, holding the top of the fin with the hand and pull continuously for a few seconds, massaging the muscle. Keep the leg straight and repeat this operation until the cramp disappears.

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3. Using the basic equipment (continued) 3.10 SOUND AND LIGHT UNDERWATER

Sound underwater travels faster than in air. It is because of this that it is very difficult to know where the sound is coming from. As sound travels in air, it first reaches one ear and then milliseconds later reaches the other ear. Signals sent to the brain allow you to recognize where the sound is coming from. In water, with the greater speed of sound, the brain cannot solve the direction. Due to refraction of light, objects in water appear 1/3 larger and 1/4 closer that they actually are. Colours are attenuated in the following order, with increasing depth, leaving only grey.:

Red 5 meters ‑ 16 feet Orange 8 meters ‑ 26 feet Yellow 11 meters ‑ 36 feet Green 20 meters ‑ 65 feet Blue 25 meters ‑ 82 feet

3.11 PROPER ASCENT

Ascend slowly, with a hand extended upward, and rotating the body 360°. This is very important because, if you hear a motor noise, you could not tell which direction it is coming from. The hand overhead will touch an object overhead before your head does.

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Page 12 Introduction ACUC - SCUBA DIVER

1. Selecting the basic 4. SELECTING THE SCUBA EQUIPMENT equipment 4.1 THE TANK AND THE TANK VALVE 2. Putting on the basic equipment 4.1.1 THE TANK

Tanks are made from mostly two types of materials: 3. Using the basic equipment  Aluminium: it is lighter, of greater capacity and is of greater size. It is most popular in North America, but corrosion problems are difficult to 4. Selecting the scuba detect except by a trained technician.. equipment  Steel: it is heavier, of smaller capacity and of smaller size. It is preferred in Europe and its acceptance is once again growing in North 5. Wearing the scuba America. Corrosion problems are easily detectable and more frequent equipment than aluminium.

Tanks come in many sizes and volumes, the most common are the 3,000 psi 6. Diving physiology 80 cu. ft. and the 3,000 psi 90 cu ft. There are larger sizes, but a 3,000 psi 80 cu. ft. tank is sufficient for most of the activities of a recreational diver in SCUBA tanks relation to time, depth and no decompression. In European countries, the most 7. Using the scuba common sizes are the 12 lts and the 15 lts steel tanks equipment The marks on a tank identify among other things, the year of construction, the manufacturer, the construction material, the recommended maximum 8. Emergency ascents pressure, the drawing / spec. of the approving agency, and the date of the last hydrostatic test done on the tank. Your Instructor will advise you on which agency regulations are in effect in your area. 9. Underwater communications For safety, the tanks require an adequate maintenance:

Visual Inspections are required periodically and the frequency changes 10. Decompression and  from country to country. Your Instructor will advise you on what different dive types frequency is required.  Hydrostatic Tests are required periodically and the frequency changes 11. Rescue and first aid from country to country. Your Instructor will advise you on what frequency is required.

4.1.2 THE TANK VALVE 12. The marine environment There are two main types of valves, the 'K' Valve without a reserve The «J» valve (recommended) and the 'J' Valve. The reserve valve need can be eliminated 13. ACUC International by using a submersible pressure gauge. ACUC does not recommend the use of the reserve valves and highly recommends the use of submersible pressure gauges. The tank valve should also have a safety rupture disc in the event of an overpressure when filling or from an increase in pressure due to heat.

4.2 THE REGULATOR WITH OCTOPUS AND GAUGE The «K» valve The single hose is the style used by over 95% of the divers today, it has it's exhaust through the second stage, near the chin, and on either side of the face. This regulator has two "stages:

The 1st stage is connected directly to the tank valve. Its function is to reduce the air pressure that leaves the tank to approximately 125 to 181 psi (this can vary according to the regulator). Once the air goes through the first stage, it travels through a low pressure port hose connection to the second stage. The protective lid (dust cap) protects the 1st stage from foreign material getting into the 1st stage. This dust cap should always be in place when the regulator is not being used.

The second stage is the one which is placed in the mouth, and the one we breath from. Its main function is to reduce the air pressure coming from the first stage to the working pressure for breathing. The second stage reduces the air pressure to the ambient pressure, thus allowing us to breath normally.

Page 13 ACUC - SCUBA DIVER

4. Selecting the scuba equipment (continued) The purge button has the function of expelling the water stored in the second stage using the air from the tank. This button must be large to facilitate finding its location especially when wearing gloves..

The exhaust ports are where the air that you exhale goes out. These are located below and to the side of the mouth. It is important to maintain these ports in a clean and good condition., otherwise, water could enter the second stage instead of leaving. It is recommended that the second stage with easy access is used or with a transparent cover to facilitate the frequent examination of the valve.

Air flow adjustment. There are some regulators that have an option to adjust the pressure required to open the valve on inspiration. This permits you to manually regulate the quantity of air that you wish to receive and the inhalation effort that you wish to put on the regulator to obtain the air. This can be beneficial in cases when, depending on work or fatigue level, more air Various regulator’s is required with less effort. 2nd stage models

High and low pressure connections. These connections, also called "ports" are located in the first stage of the regulator. Normally there are at least 2 low pressure and several high pressure ports. The low pressure connections, as their name indicates, are where instruments that operate at a reduced pressure are connected, for example, the second stage, octopus, BCD and dry suit. The high pressure connection is where the submersible pressure gauge for measuring the current pressure of the air in the cylinder is connected.

A 2nd additional stage ( “octopus “ system) is very advisable, its main function is to serve as a reserve in the event of failure of the main 2nd stage and to facilitate shared breathing, in the event of an emergency, between two people at the same time, using the same tank. ACUC highly recommends that all divers are equipped with an octopus system.

The Pressure Gauge. It is an indispensable piece of equipment for the diver of today. The pressure gauge tells you the air pressure remaining in the tank. Diving without a gauge is the same as driving a car without a gas gauge, but much more dangerous due to the possible consequences.

4.3 THE BUOYANCY COMPENSATOR

The most popular type is the Jacket (also known as the BCD). The jacket type is comfortable and easy to wear, is worn just as a normal jacket (thus its name) and the main lift bags are at the sides. It is buckled with some comfortable hooks located at the front part of the jacket. One advantage is that the jacket carries the "backpack" to fasten the BC to the tank. One must be careful when choosing a jacket so that safety is not sacrificed by comfort, and you should try to choose one that will float you face up with your head out of the water when you are in a relaxed position.. For normal recreational diving, wing type jackets that carry all or most of their flotation in the back are not recommended. This type of jacket is very comfortable but offers very little safety.

The jacket can be inflated orally or automatically using a power inflator. You must remember, however, that this air from the power inflator comes from the tank, after going through a low Jacket type pressure port in the first stage of the regulator and therefore the pressure in the tank will be Buoyancy reduced each time we fill the jacket leaving less air to breathe. All jackets should carry at least a compensator relief valve in the event of overpressure.

Also they should carry a valve, connected through a corrugated hose to the jacket, that permits the manual purging of the air. To purge the jacket manually, a special technique is needed, which we will discuss in one of the next lessons. Some jackets have a system called P.I.D. (Pneumatic Inflator Deflator. This system allows purging of the air from the jacket just by pushing a button, without any need of special techniques.

4.4 ACCESSORIES

 Depth Gauge: There are 3 main types of depth gauges: The "Capillary", is the most economic and the most accurate. Due to it's non‑linear scale, it is difficult to read at depth. The "Bourdon" type and the "Diaphragm", are more expensive but easier to read at depth. It is advisable that the depth gauge have an additional maximum depth Submersible indicator. This additional needle, will help to determine the maximum depth reached pressure gauges during the dive. Page 14 ACUC - SCUBA DIVER

4. Selecting the scuba equipment (continued)  Compass: Compasses are indispensable to navigate submerged in poor visibility or to find the return way without the need to surface to get your bearings.  Whistle: Whistles are necessary in the event of an emergency on the surface. They are easier to hear over the waves than a yell for help.  Flashlight: Flashlights are necessary for night dives, on wrecks, or solely to observe the colours at depth as they really are. Remember that all colours, unaided by artificial light disappear little by little as depth increases. Normally, in 66 feet (20 meters) unaided by artificial light, all objects appear bluish or grey.  Watch: Watches are necessary to keep track of dive time. The watch should have a movable bezel that can be adjusted to be set at the time you went below the surface. Underwater Flashlights  Pencil and Submersible Slate: These are highly advisable in order to communicate easily with your buddy, or in the event of an emergency to recalculate the decompression tables.  Plastified Dive Tables: These are indispensable in an emergency case, in order to do time and depth table calculations in order to avoid decompression stops (this subject is dealt with more in depth in advanced courses).

4.5 DIVE COMPUTERS

 Advantages: The main advantage of the dive computer is that, in addition to doing the functions of several instruments in one, they also do the decompression calculations and warn of possible excesses in time and / or depth.  Disadvantages: The main disadvantage is that they are instruments that can fail, and as Underwater slate they do several functions, if there is a problem with the computer, you will loose the necessary information to do a safe dive.

4.6 PROTECTIVE SUITS

Thicknesses. Depending on the temperature of the water, the thickness of the suit will vary. The colder the water, the greater the thickness of the suit. Remember that the bulkier the suit, the greater buoyancy. Therefore, you will have to take this into account when determining the amount of weight that you will need. ACUC decompression Different Material. Currently there are a great number of materials, from lycra to various rubber tables derivatives. New materials appear on the market each year, therefore the best thing to do is to consult with your ACUC dive store and let them advise you.

Different styles. There are four basic types of suits, with many assorted styles within each type. The four basic types are:

 Minimal protection suits: These one piece suits, manufactured with lycra or similar material, offer minimal protection against cold and friction with external objects. The thickness is minimal and the suit fits like a second skin. Normally they do not have a hood, gloves or boots. Their use is recommended for pool and very temperate waters. Also they can be worn under a neoprene suit. The Aladdin, a popular dive  Wet suits: they are of different thicknesses. Depending on the temperature of the water computer the thickness will vary. The colder the water, the thicker the suit. Normally there are 5 pieces to the suit: Jacket, pants (sometimes farmer john style), hood, gloves, and boots.  Semidry suits: designed for cold waters, normally tend to be a minimum thickness of 7 mm, their main characteristics are that the boots and the hood tend to be attached to the suit, therefore these suits tend to have only 3 pieces: Gloves, jacket with hood and farmer john style trousers with attached boots.  Dry suits: for cold waters or very cold they have the advantage of the fact that the diver remains completely dry, but the disadvantage is that the diver should take a special course in diving with dry suits before using one. Normally dry suits are 1 piece,: full suit with boots The gloves and hood are separate.

Bright colours. It is recommended that bright colours are chosen. These are more visible at the surface.

One and two piece wet suits Page 15 ACUC - SCUBA DIVER

4. Selecting the scuba equipment (continued) The correct size. A suit, with the exception of the dry suit, must be moulded to the body but without being so tight that it cuts off or restricts blood circulation. It is recommended that to dive in cold waters, the suits be custom made.

It is also important to know when to use the correct suit, since if you go in the water with little protection against the cold, you will have to cancel the dive in a short time due to cold. If, on the other hand, the suit is too thick, you will be at risk due to overheating of the skin and consequently discomfort and weariness.

4.7 THE DIVERS LOG BOOK

The objective of this type of book is to maintain a record of all of the dives and training data as well as to give divers an interesting history of their diving careers. The Log book is already Dry suits, for cold needed as a certification card in many parts of the world. water

If you do not have a log book, there are many dive operations that do not permit divers to dive without doing a previous assessment of knowledge and skills. The book is also absolutely necessary, with the ACUC Organization, to move to specialty and advanced courses. The dive log offers many advantages. For example, you have information recorded that can be used to track air consumption. In addition, through the records, you can look up information on dive sites that have previously been visited. All ACUC divers must understand the need to keep the log book updated. If you need additional sheets for their ACUC Log Book, please contact your ACUC Instructor or the closest ACUC Office.

ACUC log book

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Page 16 Introduction ACUC - SCUBA DIVER

1. Selecting the basic 5. WEARING THE SCUBA EQUIPMENT equipment 5.1 TANK CHECKING 2. Putting on the basic equipment Be sure to check the tank to ensure that there has been a recent visual inspection and that the tank is within hydrostatic testing dates. If these are out of date, do not use the tank. 3. Using the basic equipment 5.2 ASSEMBLY OF THE BC ON THE TANK 4. Selecting the scuba equipment  The first to be mounted on the tank is the BC (jacket or wing style) or the backpack (for horse collars). 5. Wearing the scuba  The backpack or the back part of the BC should be wetted first since equipment this will help to avoid the tank from slipping during the dive due to the stretching of the straps.  The backpack should be mounted so that the backpack is located in 6. Diving physiology front of the tank valve opening where the regulator fastens on. Line up the top of the tank valve with  Normally, the backpack is placed so that the top of the handle of the the top of the jacket backpack is at the same height as the upper part of the tank valve, 7. Using the scuba back pack though this can vary depending on the style of BC. equipment  The tank holding band of the backpack will be located slightly above the middle of the tank. 8. Emergency ascents  Ensure that the band is tight to the tank by lifting the tank up using the jacket a few inches above the ground and giving it a shake to be sure it is snug. 9. Underwater communications 5.3 TANK VALVE CHECK 10. Decompression and Check the condition of the O‑ring in the tank valve, where the regulator first different dive types stage is connected. If it is missing or cracked, replace the O‑ring. You should always carry extra O‑rings in your equipment bag.

11. Rescue and first aid

5.4 REGULATOR ASSEMBLY ON THE TANK VALVE

12. The marine environment  First, remove the dust cap from the first stage.  Then fasten, only finger tight, the first stage of the regulator to the tank Place the 1st stage valve so that the primary second stage falls over your right shoulder of the regulator on 13. ACUC International when wearing the tank. the tank valve

5.5 REGULATOR CONNECTION TO THE BC

 Connect the low pressure hose from the first stage to the connection on the BC.  Give it a slight tug where the connection goes in to ensure that it is fully Connect the connected. regulator hose to the jacket inflator hose 5.6 OPENING THE AIR

Once the above steps have been completed you are ready to open the air. Before doing this, it is important that the face of the pressure gauge be turned away from others. If it is defective or has been damaged, the crystal can explode. You should remember that the tank is under high pressure and this high pressure air will pass into hoses. Open the air SLOWLY until the valve is fully open and then close it about one quarter of a turn, to avoid damaging the valve and the o-rings.

NOTE: If the O‑ring between the tank valve and the regulator is damaged, it can cause a very loud pop sound. If this occurs, shut the air off immediately, purge the regulator using the purge button on the second stage, remove the Place the depth regulator from the valve and replace the O‑ring. gauge facing down when opening the air Page 17 ACUC - SCUBA DIVER

5. Wearing the scuba equipment (continued)

NEVER OPEN THE AIR WITH THE FACE OF THE PRESSURE GAUGE POINTING TOWARDS OTHERS

5.7 REGULATOR CHECKING

Now you need to check out the system.

 Press the purge button on the second stage of the regulator to ensure that it is working.  Take a few breathes on the regulator to ensure that it is working properly and that the air does not taste or smell odd. If it does, DO NOT USE.  If you have an octopus system, repeat this procedure.  Listen for any air leaks between the 1st stage of the regulator and the tank valve. If there is a leak, it may be that the 1st stage is not installed properly or there is a defective O‑ring. Shut the air off, purge the system through the 2nd stage and resolve the problem.  Check the inflator hose to the BC by introducing a small amount of air into the BC through the power inflator button.  Now check the pressure gauge and record the amount of air in the tank in your log book.

5.8 DISASSEMBLY OF THE EQUIPMENT

Disassembly of the equipment is the same as the assembly except in reverse.

 Check the pressure gauge and record the amount of air remaining in the tank in your log book.  Shut the air off at the tank valve and purge the system by depressing the purge button on the second stage of the regulator. BE SURE TO PURGE THE AIR FROM THE SYSTEM Purging the air BEFORE REMOVING THE FIRST STAGE FROM THE CYLINDER VALVE.  Dry the regulator dust cap by slightly opening the tank valve and blowing air on the dust cap.  Fasten the dust cap to the regulator first stage.  Remove the power inflator hose from the BC.  Unfasten the BC from the tank and lift the BC from the tank by lifting it up over the tank valve. Carefully dry the dust cap

Though this all may appear complicated, it is quite simple and you will be able to do it with your eyes closed by the time you have completed the course.

5.9 MAINTENANCE OF THE EQUIPMENT

 The mask, snorkel, fins and weight belt: wash in fresh water and allow to dry (not in direct sun or other source of heat). Apply silicone to all of the rubber parts from time to time except the mask strap. Check there is no corrosion on any of the metal parts. The snorkel can be washed in mild soap and rinsed thoroughly with fresh clean water.  The protective suit and it's accessories: Wash thoroughly inside and out with fresh water and allow to dry (not in direct sun or source of heat). Wash from time to time with mild detergent. Lubricate the metal parts with silicone, soap or wax.  The regulator and other equipment: Wash in fresh water and allow to dry (not in direct sun or source of heat). Ensure that you do not press the purge button or remove the dust cap from the regulator while it is exposed to water and not connected to the tank. Allow only qualified personnel to service your regulator. At least once a year the regulator should be serviced by a qualified technician. Store the regulator carefully ensuring the hoses are not bent. Page 18 ACUC - SCUBA DIVER

5. Wearing the scuba equipment (continued)  The tank: Wash the outside thoroughly with fresh water. Remove the tank boot from time to time and rinse the bottom of the tank and the boot. Ensure that the tank is not allowed to go completely empty except for visual inspection or hydrostatic testing. Never leave the tank unattended while it is standing up. Store in a dry site away from direct heat.  Buoyancy Control Device (jacket or horse collar): Wash inside and out in fresh water with the vest inflated. Empty the water and hang it half inflated to dry (away from direct sun or source of heat). Store the BC half inflated. Check for cracks and leaks. Take the BC to a qualified dealer for servicing at least once per year.

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Page 19 Introduction ACUC - SCUBA DIVER

1. Selecting the basic 6. DIVING PHYSIOLOGY equipment 6.1 MAIN GAS LAWS 2. Putting on the basic equipment Pressure is defined as a unit force applied on a unit surface, in direct proportion in the first and inversely proportional in the second. That is, the greater the force, the greater the pressure and the greater the surface area that the force is applied to, the less the pressure. To understand this 3. Using the basic concept, think of a skier. The skier does not sink into the snow while on skis because the weight (unit equipment force) is distributed over a greater unit surface area than when the skier is without skis. The customary pressure measure, "Absolute Technical Atmosphere" (ATA) equals approx. 1 kg / cm2 4. Selecting the scuba (mercury). This is also known as a BAR. For every 10 meters (33 feet) we descend in the water, we equipment will increase the pressure by one atmosphere (1 BAR).

Once this is understood, we can see the difference between Hydrostatic (gauge) Pressure and 5. Wearing the scuba Absolute Pressure. Hydrostatic or gauge pressure measures the pressure of the water above us equipment when we are submerged. As we have seen this is 1 Atmosphere (BAR) for every 33 feet (10 meters). Absolute Pressure is this Hydrostatic (gauge) pressure plus the pressure that the Atmosphere exerts, 1 atmosphere, 14.7 psi (pounds per square inch) or 1 BAR. 6. Diving physiology Therefore to calculate the Absolute Pressure exerted on a Diver at depth is as follows:

7. Using the scuba  Metric: Divide the hydrostatic or gauge depth by 10 and add 1 to the result. For example, at equipment 10 meters the Absolute Pressure is 2 Bars, at 20 meters, 3 Bars, at 33 meters, 4.3 Bars and so on. 8. Emergency ascents  Imperial: Divide 14.7 (1 atmosphere) by 33 equals .445 psi for every foot of sea water depth. Multiply the hydrostatic (gauge) depth reading by .445 and add 14.7 to the result to give Absolute Pressure. 9. Underwater communications 6.1.1 BOYLE'S LAW

Related to Pressure and Gas volumes. The pressure and gas volumes are inversely related. That is 10. Decompression and to say, the greater the Pressure the smaller the Volume and the greater the volume the smaller the different dive types pressure. Boyle's Law has great importance in diving physiology. It's correct application and understanding is important to avoid Barotraumas (injuries due to pressure) and pressure related pulmonary injuries. A good example to illustrate this law is what happens if, at depth, you inflate a 11. Rescue and first aid container with air, seal it tight and raise it to the surface.

Since you filled it at depth, where there is greater pressure, upon ascending, as the external pressure 12. The marine environment decreases, the volume of the air in the container will expand. The air, not being able to escape will burst the container. This is similar to what would happen to your lungs if you were to take a breath at depth and hold your breath on ascent. This is assuming that you are breathing air at pressure as you would be doing while on SCUBA. 13. ACUC International 6.1.2 HENRY'S LAW

Henry's Law is related to pressure and gases dissolving in a liquid. The amount of gas that will dissolve in a liquid is directly related to the pressure exerted on that gas. As pressure increases more gas will dissolve in a liquid and as pressure decreases, the excess gas will come out of solution. Henry's Law has great importance in the physiology of diving. Its application and comprehension is important to avoid decompression sickness.

An example of this is when you quickly open a carbonated beverage. The beverage is carbonated under pressure and when the beverage is opened, the gas comes out of solution and causes the beverage to bubble. Something very similar to this occurs if you quickly change the pressure that surrounds you, for instance ascending quickly.

According to Henry's Law the tissues in our body are absorbing gases in quantities directly related to the existing pressure of the depth you find yourself. The deeper you descend and the greater amount of time we spend at depth, the more the tissues of our body will absorb more gas. These excess gases do not present a problem while dissolved. On ascending, sufficient time must be allowed to permit the tissues to "off‑gas".

To remain too deep for too long, to later ascend to the surface without having given enough time to the organism to absorb those gases, can cause the formation of gas bubbles in the blood, due to the change of pressure. These bubbles are those that cause decompression illness. To avoid this type of accident, it is indispensable that the diver respects Henry’s law. Page 20 ACUC - SCUBA DIVER

6. Diving Physiology (continued) It is for this reason that divers must have an understanding of the calculations of decompression tables, as well as the maximum ascent rate to the surface..

There are other laws that affect us when we dive, but we will study them in advanced courses, since according to the standards of this course, as long as they are followed, these laws will not have effects in a diver of this level. These laws are mainly the Law of Dalton, the Law of Charles and the General Law of Gases.

REVIEW BOYLE'S LAW Pressure and Density are directly related and Volume of a gas is inversely related.

PHYSIOPATHOLOGICAL Barotrauma and Pulmonary overpressure RELATIONSHIP

HENRY'S LAW As pressure increases, more gas will dissolve in a liquid and

as pressure decreases, dissolved gas will come out of

solution.

PHYSIOPATHOLOGICAL Decompression RELATIONSHIP

6.2 GENERAL ANATOMY

6.2.1 SINUSES:

The sinuses are air cavities that are found in the bones on the cranium. The main ones are the frontal sinuses and the maxillary sinuses.

 The frontal sinuses are located in the frontal bone, above the orbits to both sides of the mid line. They have narrow and winding drainage conduits that reach the nostrils.  The maxillary sinuses are found in the face at cheek level. Their drainage conduits are short and relatively broad and drain into the nostrils.

The sinuses are all covered with mucous membranes and in the event of a cold or infection swells and produces mucus. These changes may result in the drainage passages being obstructed by mucous, and could cause a diver to suffer a barotrauma.

The different sinuses 6.2.2 CIRCULATORY SYSTEM

The circulatory system is comprises the heart, lungs and blood vessels of the body. The heart is located in the middle third of the thorax, slightly towards the left side of the body. It is a hollow organ, split into four compartments, a right auricle and ventricle and a left auricle and ventricle. The arteries carry oxygen rich blood ‑ low in carbon dioxide ‑ from the heart to all parts of the body.

The veins carry carbon dioxide rich blood ‑ low in oxygen ‑ back to the heart. From the heart blood is sent to the lungs where the excess carbon dioxide is eliminated and oxygen is acquired for transport back to the heart and then on to the body.

The capillaries permit blood to flow from the arteries to the veins. They are the smallest parts of the circulatory system. The capillaries relinquish their oxygen and other nutrients to the body tissues, and collect the waste material and carbon dioxide from the body tissues.

The blood is the liquid element that circulates through the vessels. It is composed of a liquid part called the blood plasma and a solid part called blood cells. The types of blood cells are:

 Red corpuscles or erythrocytes, that transport oxygen bound to the haemoglobin that they contain  White cells or leukocytes that are in charge of the body defences.  Platelets or thrombocytes, are responsible for blood coagulation. Page 21 ACUC - SCUBA DIVER

6. Diving Physiology (continued) In terms of function we can consider the heart to be split into two parts: the right heart and the left heart.

The blood originating from the whole body arrives to the right auricle through the vena cava. From the right auricle it passes to the right ventricle, and from there to the lungs, where gas exchange will occur. This is called the Minor Circulation.

The left auricle receives the blood from the lungs or the Small Circulation, enriched in oxygen. From there it passes to the left ventricle and leaves through the aorta to travel to the whole body, to return again to the right auricle. This is called the Major Circulation.

6.2.3 RESPIRATORY SYSTEM

The respiratory tree and the alveoli (from Thibodeau CA and Anthony CP: The structure and work of the body, 8th edition, St Louis, CV Mosby)

The Respiratory System is split into the upper and lower airway. The upper airway is made up of the nostrils, pharynx, larynx and trachea. The lower airway is formed by the bronchus, bronchiole and alveoli.

The lungs are structures that surround the bronchus as support and are found on each side of the thorax. The lungs are surrounded by a double membrane called the pleura. The air that we breathe enters the nostrils (in a diver, due to the equipment that is used air enters by the mouth), is heated, humidified and filtered. From there it continues to the pharynx, a common conduit for the Respiratory System and the Digestive System.

From the pharynx it continues to the larynx. In the larynx there is a narrowing formed by the vocal cords that is the glottis.

From the larynx it goes to the trachea, a conduit formed by some cartilaginous rings. The trachea is split into two, giving origin to the right bronchus and the left bronchus. The bronchi turn into a multitude of bronchiole, which go to the final portion where they form grape like sacks that are the pulmonary alveoli.

Page 22 ACUC - SCUBA DIVER

6. Diving Physiology (continued) The pulmonary alveoli, thousands in number, are the functional unit of the Respiratory System. This is where the air breathed meets with the blood from the capillaries, and through the alveolar capillary membrane the gaseous exchange takes place. This consists of the diffusion of the carbon dioxide from the blood to the air and the oxygen moves from the air to the blood.

6.3 EFFECTS OF PRESSURE

EAR AND SINUS BAROTRAUMA (Boyle’s Law)

PREVENTION Equalization of the internal and external pressure

SYMPTOMS Earache, Disorientation, Hemorrhage, Dizziness

TREATMENT Mild Analgaesia, Decongestant, Medical Attention. No further diving until resolved

EMBOLISM AND PULMONARY OVERPRESSURE (Boyle’s Law)

PREVENTION Attempt to breath normally at all times. NEVER HOLD YOUR BREATH

SYMPTOMS Thoracic pain; Respiratory difficulty; Cough; Bloody foam; Unconsciousness; Weakness, Confusion; Seizure TREATMENT Keep victim flat; Give fluids if fully conscious; Protect the airway; 100% oxygen; Transfer to Chamber DECOMPRESSION SICKNESS (Henry’s Law) Plan the dives before doing; Do not ascend too quickly; Observe the depth/time limits PREVENTION indicated in the Decompression Tables; Adjust these limits to your personal and environmental conditions. SYMPTOMS Weariness; Itchiness or peculiar rash; Muscular and/or joint pains

TREATMENT 100% Oxygen; Give liquids (water) if fully conscious; Transport to Hyperbaric Chamber

DIZZINESS (Boyle’s Law) PREVENTION Gentle effective equalization of the middle ear.

SYMPTOMS Dizziness; Disorientation; Imbalance; Nausea Hold onto something firm; Don't change depth until you can breath, then ascend; Seek TREATMENT medical attention if symptoms persist.

6.4 ALCOHOL AND DRUGS

You should not dive while under the influence of drugs or alcohol for the same reasons that you should not drive a car. When you drive a car you are in the environment in which you live. When you dive, you are a strange environment to your body. The effects of pressure, together with the physical laws that govern diving, all combine with the effects of alcohol or drugs in a cocktail that can have deadly results. To prevent these problems, avoid alcohol or taking drugs 3 or 4 hours before or immediately after diving to allow for off gassing without complications. Increase your uptake of non carbonated fluids to prevent decompression sickness from dehydration due to the dive.

6.5 DIVING IN COLD WATERS

The normal body temperature is 37º C (98.6º F) and the skin is 34º C (92º F). Heat is drawn away from your body 25 times faster in water than in air. A reduction of the body temperature would cause what is known as Hypothermia. To prevent hypothermia use adequate protection and do not stay too long in the water. The zones that you should protect are the head, underarms, inside of the groin area and thighs which have less insulation. If you begin to shiver while diving, you should discontinue the dive immediately. If you stop shivering this does not mean that the danger of hypothermia has passed, but rather may mean exactly the opposite, it can mean, in fact, that the degree of hypothermia has advanced and gone to dangerous limits. In the event of hypothermia, the first aid is to dry and protect the body from wind and then gradually warm the person, putting special attention to the trunk. DO NOT GIVE ALCOHOLIC BEVERAGES

In more advanced ACUC courses and in the Specialty courses such as First Aid, Rescue and Oxygen Administration more detailed information is offered on Diving Physiopathology. Request information from your ACUC Instructor or contact the nearest ACUC Office.

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Page 23 Introduction ACUC - SCUBA DIVER

1. Selecting the basic 7. USING THE SCUBA EQUIPMENT equipment 7.1 HOW TO PUT THE SCUBA EQUIPMENT ON 2. Putting on the basic equipment For the purposes of this manual, the Jacket BC will be used since most training now takes place using this style of equipment. The horse collar BC involves a little more training since the back pack that attaches to the tank is separate 3. Using the basic from the BC. In all cases remember that the weight belt goes on last and is the equipment first piece of equipment that comes off.

4. Selecting the scuba equipment 7.2 FLOODING AND EMPTYING THE MASK

5. Wearing the scuba One of the most important skills that all divers will have to be able to accomplish before obtaining certification. Water can be emptied from the mask equipment while underwater simply by lightly holding the face of the mask with one hand at the point closest to the surface and gently breathing through the nose, as the air forces the water out of the mask. Obviously, the smaller the mask 6. Diving physiology volume, the easier it will be to clear the mask, as less air is required to empty Clearing the mask water from the mask. 7. Using the scuba

equipment 7.3 PURGING THE REGULATOR

8. Emergency ascents This can be accomplished in two ways: using the purge button usually located in the centre of the second stage of the regulator or by exhaling into the mouthpiece of the regulator replacing the water in the second stage with air. It 9. Underwater is important to purge the regulator before inhaling any time the regulator is communications taken out of the mouth under water.

10. Decompression and 7.4 BREATHING WITH THE REGULATOR different dive types

When using the regulator, breathing is done normally, except for the fact that 11. Rescue and first aid you inhale only through your mouth and exhale through your mouth rather than your nose. Exhaling through your nose can cause water to flood the mask since the overpressure in the mask caused by the exhalation will push the mask away from the face, breaking the seal. When descending, however, you 12. The marine environment must exhale a small amount of air through the nose in order to equalize the internal mask pressure with the external water pressure to avoid a mask squeeze. 13. ACUC International It is necessary for all divers to be able to breathe through the regulator with or without wearing a mask (this is one of the reasons for good training with equipment such as snorkel breathing without a mask).

When practising this exercise inhale through your mouth and exhale through your nose to avoid getting water up your nose. What is important to remember is DO NOT INHALE THROUGH THE NOSE.

7.5 BUDDY BREATHING

Buddy breathing is a technique for handling an emergency out of air situation where the donor, the diver who has air, shares his air with his buddy using a common second stage while ascending to the surface. This technique requires a large amount of skill and must be practiced often in order for buddy breathing to be carried out effectively and safely.

In cold water, (under 10 degrees C ‑ 50 degrees F) there is another problem with buddy breathing. Due to the cold water, exposed surfaces such as your cheeks and mouth can become numb. This can make the effort to buddy breath dangerous for both the donor and the receiver.

There are two correct positions for buddy breathing, depending on the type of emergency. Page 24 ACUC - SCUBA DIVER

7. Using the scuba equipment (continued) If the emergency occurs in a cave or a place where you must travel on the horizontal because there is no direct ascent to the surface, the Side by Side method would be used. If a direct ascent to the surface is possible, then the Face to Face position is used.

In both methods, THE DONOR WILL ALWAYS MAINTAIN CONTROL OF THE SECOND STAGE OF THE REGULATOR. At no time should the victim be allowed to control the second stage of the donor's regulator

In the Side by Side method, the correct way to pass the mouthpiece is for the donor (the person with air) to be positioned to the right side of the victim, slightly below the victim and holding the victim with the left hand at the tank valve or the shoulder strap of the BC. In the Face to Face method, the victim and donor are facing each other. The donor grasps the jacket of the victim with the left hand and tries to maintain eye contact with the victim. One of the correct methods of holding The donor is responsible for positioning the second stage mouthpiece at the mouth of the victim. the 2nd stage when Never release the second stage to the victim. The donor must remember that the victim may not doing horizontal have sufficient air in the lungs to purge the second stage and therefore must allow free access to buddy breathing the purge button by the victim. The donor must also be prepared to purge the regulator for the victim.

One method to ensure that the second stage is purged and the victim can see the second stage easily is to press the purge button while passing the regulator to the victim for the first time. This removes the need to position the second stage slightly tilted down to avoid free flow. After the initial air share, the procedure is to pass the second stage back and forth positioned with the mouthpiece slightly down.

In all cases of buddy breathing, the donors as well as victims should be trained to take two rapid inhalations and exhalations on each exchange. The donor should be prepared to allow the victim to take 3 to 4 breaths while the donor only takes 2 until the victim is calmed, especially at the beginning of the emergency. Since buddy breathing means that a diver is submerged without working equipment, it is important that the donor should observe the victim. If the victim is not exhaling, the donor must try to get the victim to exhale by pointing to his own mouth and blowing small amounts of bubbles out. If this does not work, any ascent must be stopped until the victim exhales air. The donor will have to control the direction of the victim and must be prepared to inflate or deflate the victim's BC as well as his own.

AT ANY TIME THE MOUTHPIECE IS NOT IN THE MOUTH, AIR MUST BE EXHALED CONTINUOUSLY (especially in situations where there is an ascent to the surface).

The donor is therefore responsible for the safety of himself as well as the victim. Nevertheless, if When the regulator problems arise, the primary responsibility of the donor is for his own safety, since the donor is is not in your mouth, the one with the source of air and it is much worse to have two panic victims rather than one. If it always exhale becomes necessary, forceful means must be used if for example the victim refuses to give back slightly the second stage. One effective method is to forcefully pull on the second stage. You may loose the mouthpiece but you can still breath on the regulator without the mouthpiece.

7.5.1 OCTOPUS BREATHING

A more effective and safe method is Octopus Breathing. As you can see from the above, buddy breathing can be dangerous and requires quite a bit of training and practice. Fortunately, more and more divers are opting to use octopus systems (two second stages) or other means of alternate air supply. Using this system, in the event of an emergency, each diver has his own breathing device which helps in an emergency situation.

7.6 LOST REGULATOR RECOVERY

There are two ways to recover a regulator that has been accidentally removed from your mouth. The first method is simply of pushing on the base of the tank with your left hand while reaching over your shoulder with your right hand to find the tank valve. Once you have found the hose for the second stage, follow the hose to the second stage. The second method consists of, while in the horizontal position looking downward, turn to your right 90• degrees so that your right side of the body is pointing down. Start a sweep with your right hand beginning close to your body near your knee and sweeping in an arc towards your head.. Your arm will pick up the second stage and hose in the sweep. Page 25 ACUC - SCUBA DIVER

7. Using the scuba equipment (continued) It is important to remember to continuously exhale slowly any time you are underwater and your second stage is not in our mouth.

Buddy breathing must be practiced often and even so, it will be very difficult to do in a real emergency. For this reason all ACUC Instructors and Divemasters are obligated to carry octopus systems or other alternate air sources. ACUC recommends that you, for your own safety, DO NOT DIVE WITHOUT CARRYING AN OCTOPUS SYSTEM OR ALTERNATE AIR SOURCE. ALSO DO IT FOR THE SAFETY OF YOUR BUDDY, AND, FOR YOUR OWN SAFETY, DO NOT DIVE WITH A BUDDY WHO DOES NOT CARRY AN OCTOPUS SYSTEM OR ALTERNATE AIR SOURCE.

7.7 DESCENT WITH THE BC

Depending on the type of BC, mainly the type of inflator of the BC, there are several ways of descending with the BC All ways have a common denominator; air must be let out of the BC in order to descend. In BCs with older mechanisms, the descent method is the following: In a vertical position at the surface, stretch the left arm upward, holding the inflator, press the deflate button to let the air out of the BC. Some of the other BCs have a built in dump valve in the hose mechanism. All you need to do is pull on the inflator hose and the valve will open. Other BCs have a remote / overpressure dump valve located near the bottom of the BC which is good when you are descending head first down a shot line. This action can be helped by pressing the BC against your body with your right hand and arm. It can also be helped by forcing your body up out of the water with a scissors kick and then allowing your body weight to push you down. (similar to a feet first surface dive in snorkeling.)

7.8 CONTROLLED ASCENT WITH THE BC

It is important that as long as you are ascending, free from the shot or anchor line, to carry your hose and inflator/ deflator of the BC in the left hand. Remember that as you ascend, due to the decrease in pressure, the volume of air in you BC will increase (Boyle's Law). This expansion will increase your buoyancy and therefore it will be necessary to let air out little by little to avoid a too rapid or uncontrolled ascent. If you are travelling up an anchor line, grasp the line and use it as a brake if you find yourself ascending too fast. You can then hold yourself still on the line while you eliminate some air from your BC. Even if you exhaust too much air, you will not sink back down because you are holding on to the line.

7.9 RESTING ON THE SURFACE WITH A B.C

Once on the surface, if you chose to rest, simply inflate your BC with air from your tank using the inflator button and lie slightly on your back with your arms crossed on top of your chest. This is the safest and least stressful method. To orally inflate your BC, hold the inflator mouthpiece in your mouth, push the exhaust button to open the valve into the BC and blow air into your BC. Before you take your mouth away from the mouthpiece, be sure to let go of the exhaust button or the air that you exhaled into the BC will come right back out. This method requires practice to be able to do to correctly and for you to be comfortable doing it, especially if you are on the surface in choppy water.

7.10 THE PROPER TECHNIQUE FOR OBTAINING NEUTRAL BUOYANCY AT THE BOTTOM

Upon reaching the bottom, lay in a horizontal position facing the bottom. Begin to inflate your BC either with the power inflator( best method) or manually, little by little. (Use the 1 in 5 technique, that is inflate for 1 second and wait for 5 seconds to see the effect.) Each time you inflate, hold your breath for a couple of seconds to see if your chest rises off the bottom. The tips of your fins should always be in contact with the bottom.

Let the air out of your lungs, and this will cause the upper part of your body to descend. If you fall quickly, introduce a little more air into your BC and repeat the previous steps. If, on the other hand, your body rises quickly, this indicates that there is too much air in the jacket and you must let some air out of the BC. The objective is to introduce the correct amount of air into the BC so that you rise and fall slightly with each inhalation and exhalation.

7.11 TECHNIQUE FOR MAINTAINING NEUTRAL BUOYANCY DURING THE DIVE

Maintaining neutral buoyancy is important for diving in a safe and comfortable way, and also in protecting the environment. Page 26 ACUC - SCUBA DIVER

7. Using the scuba equipment (continued) A lot of damage is caused by poorly trained divers with their bodies and their fins by not having control of their buoyancy. If you try to obtain the "neutral point" as described in the previous section, then for the rest of the dive, as long as you maintain a stable depth, you will be able to easily control your body position with your lungs without any need to inflate or deflate the BC

If you want to ascend a few inches (less than 2 feet), you would simply breathe in, being careful not to hold your breath any more than a couple of seconds. If you want to descend a little, exhale some air from your lungs. Larger depth changes will require you to inflate or deflate your BC to achieve neutral buoyancy at the new depth.

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Page 27 Introduction ACUC - SCUBA DIVER

1. Selecting the basic 8. EMERGENCY ASCENT equipment 8.1 WHEN AND HOW 2. Putting on the basic equipment The emergency ascent should be one of the last options to be used in the event of an emergency. It should be avoided, if at all possible, by opting to share air with your buddy if he is nearby. The specific situations should be 3. Using the basic evaluated carefully before deciding on an emergency ascent. As an example, equipment let's look at two situations. First: You are at 33 feet (10 meters) of depth, swimming against a current, and your buddy, who has an octopus system, is 4. Selecting the scuba about 23 feet (7 meters) in front, swimming in the same direction that you are. equipment You find yourself out of air. What should you do? In this case, aside from the fact that you have already broken two diving safety rules (excessive distance 5. Wearing the scuba between buddies and allowing yourself to run out of air), the most correct equipment answer would be to perform an emergency ascent. You should consider that you are not very deep, ‑only 33 feet (10 meters)‑ that your buddy is about 23 feet (7 meters) away but, since he is in front and swimming away, you must 6. Diving physiology swim quickly and against the current to reach him, something that is more difficult and consumes more energy (and therefore more air) than to ascend directly to the surface. Also you could try to attract his attention by banging on 7. Using the scuba your tank with a knife, but this can make you lose very valuable time. equipment Second: You are at 100 feet (30 meters) of depth, there is no current, your buddy, who carries an octopus system, is in front of you some 27 feet (8 8. Emergency ascents meters) away. You find yourself out of air. What should you do? In this case, aside from the fact that you have already broken two diving safety rules (excessive distance between buddies and allowing yourself to run out of air), 9. Underwater the most correct answer would be to go towards your buddy and try to attract communications his attention by banging on your tank with a knife. You should consider that you are quite deep, that your buddy is 27 feet (8 meters) away but there is no 10. Decompression and current. This means that by swimming quickly you can reach him easily and different dive types with less risk than ascending 100 feet (30 meters) to the surface.

This means you should act according to the specific situation. What is most 11. Rescue and first aid important is NOT TO PANIC!! A controlled ascent, without air, from 100 or 130 feet (30 or 40 meters) is possible to do if the ascent is made correctly and you keep calm.

12. The marine environment When trying to get someone's attention underwater, for example by hitting your tank with a knife, it can be more effective to make the noise when the person is NOT blowing bubbles (breathing out). The noise from the bubbles 13. ACUC International could interfere with the noise you are creating.

8.2 CONTROLLED EMERGENCY ASCENT

There are several things to remember when doing a controlled emergency ascent:

 If you have good buoyancy control (that is you can "hover" in one place in the water), it is not necessary to drop your weight belt since, by kicking upwards a few feet the change in pressure will make you positively buoyant. Having no weight belt could hinder control of your ascent especially in the last few feet to the surface. If, however, you are negatively buoyant, then the weight belt must be dropped.  Keep the regulator in your mouth and continue to try to breath normally during the ascent. (As the pressure is reduced the volume of air remaining in the tank and hoses may increase enough to allow for a few breaths).  Continue to hold the power inflator/deflator in your left hand and let out air as the BC expands to control the rate of ascent. A position that will  Continue to look up and monitor your depth gauge and watch to ensure slow down the rate you are not ascending to quickly. of ascent when doing an emergency ascent Page 28 ACUC - SCUBA DIVER

8. Emergency ascent (continued) 8.3 EMERGENCY ASCENT WITH A BC

The last option and the most dangerous one is an uncontrolled buoyant ascent. It consists of dropping the weight belt, inflating the BC and allowing yourself to be propelled to the surface.

8.4 ASCENT WITH SHARED AIR

This is the safest method. It has already been explained in the previous chapter.

8.5 CORRECT WEIGHT BELT REMOVAL

Releasing the In a vertical position, open the buckle with your right hand, pull the belt away from your body and weight belt in case extend your arm. Let the belt fall. of an emergency

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Page 29 Introduction ACUC - SCUBA DIVER

1. Selecting the basic 9. UNDERWATER COMMUNICATIONS equipment 9.1 THE BUDDY SYSTEM 2. Putting on the basic equipment As a diver, you must never dive alone. It is further recommended that even when diving in groups, these groups should be in pairs. That is, in two (preferable), four, six, etc. so that no one is without a buddy. The buddy system begins before the dive and continues during and after the dive. The 3. Using the basic buddies must be sure that they are familiar with the same underwater signals, as well as each other's equipment equipment. They should help each other putting the equipment on. Before entering the water they should decide who will "lead" and who will "follow". They should be in agreement as to the purpose 4. Selecting the scuba of the dive, even if it is simply to have a look around. equipment Once in the water, the distance between the buddies will depend somewhat on the visibility but in no case should they be any more than 12 feet (3.8 Meters) apart at any time. In poor visibility, the buddy 5. Wearing the scuba team should be closer together and, in silt conditions, should even consider wearing a buddy line. equipment They should monitor each others air supply to know how much air is remaining. When one buddy decides to go to the surface, the other buddy will go with him. The needs and experience of the less expert of the buddy pair should always of most importance on the dive. They should always be in the 6. Diving physiology position of establishing visual contact with each other.

If your buddy pair becomes separated underwater, the procedure to follow should be: look for your 7. Using the scuba missing buddy for 30 seconds, if he cannot be seen, ascend a few feet, look for him (or his bubbles) equipment for another 30 seconds , and if he still cannot be seen, ascend to the surface and wait for him for about 1 minute. If he does not appear, inform the Divemaster on the boat or the person in charge of the dive. 8. Emergency ascents

9. Underwater 9.2 UNDERWATER HAND SIGNALS

communications The hand signals (see next pages) should be made slowly and clearly. On night dives, aim the beam of the flashlight at the hand making the signals. Be careful not to shine the beam directly into your 10. Decompression and buddy's eyes. The most common ones are shown next. different dive types

11. Rescue and first aid

12. The marine environment Followed by >

13. ACUC International

Low on air Let’s go up

Followed by >

Give me air

Or by >

Out of air

Let’s go up Page 30 ACUC - SCUBA DIVER

9. Underwater communications (continued)

Danger Stop

Ok (underwater) Ear problems

Ok (on the surface)

Something is wrong Where is your Look buddy?

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Page 31 Introduction ACUC - SCUBA DIVER

1. Selecting the basic 10. DECOMPRESSION AND DIFFERENT DIVE TYPES equipment 10.1 THREE DIFFERENT TYPES OF DIVES 2. Putting on the basic equipment There are three different types of dives. The times specified below could change depending on the decompression tables used:

3. Using the basic  Single Dives: Dives that are made 18 hours after or 18 hours before the previous or next equipment dive.  Continued Dives: Dives that are made with less than 15 minutes elapsed time from the 4. Selecting the scuba previous dive. When working out decompression calculations, these dives are considered equipment single dives, taking the maximum depth reached on any of the dives and adding the dive times together. 5. Wearing the scuba  Repetitive Dives: Dives that are made with more than 15 minutes and less than 18 hours equipment after the previous dive.

6. Diving physiology 10.2 DIVE TIME AND RATE OF ASCENT

The dive time is calculated from the moment that you begin descending until the beginning of your 7. Using the scuba final ascent to the surface. ACUC recommends that to increase safety, the dive time is equipment calculated from the moment you begin your descent until you reach the surface at the end of the dive. Your ascent rate should be kept to 50 feet (15 meters) per minute, plus or minus 10 ft (3 m) per minute. Another way to measure the speed is to follow up, without surpassing, the smallest 8. Emergency ascents bubbles exhaled by the diver.

ACUC recommends that on all dives over 40 feet (12 meters) of depth, repetitive dives or dives of 9. Underwater more than 30 minutes duration, always do a safety off gassing stop for 2 to 3 minutes at 15 to 20 feet communications (5 to 7 meters) of depth, (even if the tables do not require a decompression stop).

10. Decompression and different dive types 10.3 REPETITIVE GROUPS

The repetitive groups are a series of letters, that define the quantity of Residual Nitrogen (expressed 11. Rescue and first aid in minutes) remaining in your body based on the depth, time, or surface interval, after one or several dives and the surface interval.

12. The marine environment 10.4 SURFACE INTERVAL

13. ACUC International The surface interval is the time that elapses from the moment the diver breaks the surface of the water after the dive, until the moment of the beginning of the descent on the next dive. The minimum surface interval is 15 minutes, less than this amount of time is not considered to be a surface interval.

10.5 RESIDUAL NITROGEN

Residual Nitrogen is the amount of Nitrogen remaining in the human body after doing one or several dives. The Residual Nitrogen is reduced during a surface interval and increases during the dives. Residual Nitrogen is measured with the letters of the repetitive groups.

10.6 NO DECOMPRESSION LIMITS

Due to Henry's Law, the tissues and liquids of the human body will absorb greater quantities of gases as pressure increases. At a given depth, your body will absorb nitrogen until your body reaches a point of saturation. Any attempt to add more nitrogen would cause your body to become supersaturated and bubbles would form. As the pressure decreases on ascending, the similar result happens. This change in pressure (less) causes your body to be supersaturated and the nitrogen comes out of solution causing DCS (Decompression Sickness). Dive tables are designed so that as depth increases the amount of time you can stay at that depth without decompression decreases. If these limits are surpassed, then you will need to do one or several decompression stops, of varied duration and depths, to give your body the opportunity to "off gas" the excess gases before ascending to the surface. But this is outside of the limits of what a person taking this course can do. We look at this in more details on other, more advanced courses. Page 32 ACUC - SCUBA DIVER

10. Decompression and different dive types (continued) In cases of very deep or long dives, decompression stops can also be done at greater depths, but this information and the calculations involved are materials for more advanced and specialty programs (Deep Diving). The objective for the basic scuba diver is never to stay more time, or to descend to more depth (remember, your maximum allowable depth is 15 meters), than the tables indicate so that mandatory decompression stops are always avoided. Decompression dives MUST be planned previously and carefully.

10.7 HOW AND WHERE ACTUAL DEPTH IS MEASURED.

The depth is measured based on your deepest dive recorded during the dive. It is suggested that you put your depth gauge at chest level from time to time to get an accurate reading of the depth.

10.8 DIVING AND FLYING

Since the passenger cabins of most commercial flights are pressurised, a diver should never fly until their body is free of Residual Nitrogen. The pressure that exists in the cabins of the planes could cause Residual Nitrogen that remains in the diver to come out of solution and could cause Decompression Sickness. This is also true of driving or walking over mountain ranges of more than 1,000 feet (300 meters) right after diving. Extreme precautions and a safe surface interval should be taken in these circumstances

10.9 USE OF DECOMPRESSION TABLES ACUC decompression 10.9.1 OBJECTIVE OF THE TABLES tables

The primary objective of the tables, through their proper use, is to help you plan a dive with a large degree of safety. All certified divers should know the meaning and how to use the tables. The tables indicate to the diver the depth and maximum time of a dive (or dives) to avoid decompression stops. Should the unforeseen happen and you stay submerged at a given depth over the allowed time, knowledge of the tables will give you the information as to where it is needed to do decompression stops, at what depth and the duration of the stop.

It is very important that recreational divers avoid doing dives where decompression stops are needed, as this is a practice that can be very risky.

10.9.2 INTRODUCTION TO THE DIVE TABLES

Decompression tables are fully dealt with in the Open Water Diver course. For the purpose of this course, where certification holders can only dive to 15 meters / 50 feet, your Instructor will show you how to use the tables for NO decompression diving.

Since when concluding this course, you will always dive under direct supervision of a Divemaster and also, to a maximum depth of 15 meters (50 feet) and therefore, you will not need to do mandatory decompression stops, the decompression tables are not included in this course. Nevertheless, the ACUC tables are available in a plastified version for its use underwater. If you want to acquire them, request them to your instructor, distributor or to the nearest ACUC office.

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Page 33 Introduction ACUC - SCUBA DIVER

1. Selecting the basic 11. RESCUE AND FIRST AID equipment 11.1 DEFENCE POSITIONS 2. Putting on the basic To do a safe and effective rescue the rescuer will have to evaluate all of the variable aspects before equipment he approaches a panicky victim: the environment, the size and force of the victim in comparison to the rescuer, the weariness level, etc. The best is to avoid personal contact if possible by throwing 3. Using the basic something that floats to the victim. If it is decided to approach the victim, it should be done with great equipment care, giving advice and direction to the victim ("Inflate your BC!!", "Calm yourself!!" "Ditch your weight belt!!" etc.). 4. Selecting the scuba ‑ equipment The rescuer should keep a safe distance (minimum 10 feet 3 meters) from the victim and assume the "reverse and ready" position and convince the victim to relax. (It is important to add that the "reverse and ready" position is only effective as a way to move quickly away from the victim while 5. Wearing the scuba keeping an eye on him). Once the victim has relaxed, have the victim use his/her own power to swim equipment to the boat or shore, whichever is closest. If the victim is tired, have the victim turn around with his / her back to you and approach with caution from the rear. Grasp the tank valve, BC, or have the victim extend an arm behind over their head and grasp their wrist. 6. Diving physiology If the victim continues to panic, stay away until the victim becomes tired. Then approach only from the rear, regulator in your mouth, in case the victim takes you under. If the victim grasps the rescuer, 7. Using the scuba the rescuer should submerge. The last thing a diver in panic wants is to go underwater. The only equipment thought in the victim's mind is to get out of the water, not under. This should cause the victim to let go. At this point, swim away and then assume the "reverse and ready" position again and go through the process once more. If the above technique does not work, inflate your BC and try to protect your 8. Emergency ascents regulator from being pulled from your mouth. Get yourself as buoyant as possible and try to make the victim buoyant. The object of the exercise is to have the victim obtain neutral buoyancy. In over 90% of the cases, once this is accomplished, the victim will calm down. 9. Underwater communications UNDER NO CIRCUMSTANCES SHOULD THE RESCUER APPROACH THE VICTIM WHEN THE VICTIM IS IN A STATE OF PANIC. 10. Decompression and different dive types

11.2 TOWS 11. Rescue and first aid Your Instructor will explain and have you practice the following tows: tank valve tow, tired diver tow (by wrist), cross chest carry, tired diver push. It is important to remember that in any tow, the head 12. The marine environment should be kept as much as possible inside the water. A head outside of the water weights around 8 kilos / 17,5 lbs and in the water it hardly weights anything, therefore it is easier to tow and be towed.

13. ACUC International 11.3 FIRST AID

The first priority is the ABCs ‑ Airway, Breathing, Circulation. 100% Oxygen should be administered to the victim as soon as possible. While detecting problems with the Circulation and Breathing is relatively easy, detecting problems with the nervous system is more complex. ACUC advises that for this purpose a Neuro‑Cue‑Card be used. The second priority is to check the whole body by looking, hearing and feeling the body from head to toe. The victim should be moved to where s/he can obtain medical attention as soon as possible. Try to begin the evacuation of the victim even while doing the above. IMPORTANT Many countries require that divers carry accident insurance. If you do not 11.4 VICTIM TRANSPORTATION already have insurance, r e q u e s t t h e A C U C Transport the victim on a stretcher if possible. A simple stretcher can be made with two poles and a insurance from your wet suit. A blanket should be placed under and over the victim. This will help to keep the victim warm Instructor or the nearest (treat for shock) and help transferring the victim to a bed or other surface. Speak calmly to the victim ACUC Office. if conscious. Continue 100% Oxygen to the victim as long as it is available. Try to keep the victim’s head at a lower level than the victim’s feet.

The information listed in the First Aid and Rescue portion of this manual is basic. If you are interested in acquiring further knowledge on these subjects, your ACUC Instructor or nearest ACUC Office can give you more information on the courses for First Aid, Rescue, and Oxygen Provider Programs.

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Page 34 Introduction ACUC - SCUBA DIVER

1. Selecting the basic 12. THE MARINE ENVIRONMENT equipment One of the great myths associated with diving is that the underwater environment is dangerous. Nothing could be further from the truth. The 2. Putting on the basic underwater environment is different to ours, but it is a part of our world where equipment quiet and tranquility abound. By the end of this module you will see that the most dangerous thing in the sea is man. Nevertheless, though we do not have 3. Using the basic to fear the underwater environment, we should always respect and know that, equipment in 99% of the cases, man is to blame for the dangers caused to himself.

4. Selecting the scuba 12.1 CORAL equipment There are several types of coral. Some coral produce irritations when touched. Corals form part of the underwater environment. They are the 5. Wearing the scuba ecosystem necessary for the shelter and reproduction of marine life. Coral equipment should not be touched or broken. Touching the coral, aside from being dangerous, can destroy it, even if it does not break. In some coral, a centimetre takes over 2 years to grow. You must take extreme care so as not 6. Diving physiology to break the coral, especially with your fins. Always keep at least 2 feet away from the coral.

7. Using the scuba equipment 12.2 SHARKS AND BARRACUDAS

8. Emergency ascents 12.2.1. Sharks

Of the many species of sharks, only a few are dangerous to man, although 9. Underwater normally this is not the case unless they are provoked. The majority are communications curious rather than dangerous. Sharks are attracted by blood, noises and erratic movements, such as those produced by a speared fish. The female menstrual period DOES NOT produce a sufficient quantity of blood to attract White shark 10. Decompression and sharks. In the event of an attack, You should protect our backs (placing different dive types yourself against rocks or your buddy). Never lose sight of the shark. Never flee if the shark chases you, this will attract him more. If the shark gets too close and, if you have no other choice, try to hit the shark on the snout, but 11. Rescue and first aid never with an unprotected hand, as the skin of the shark is very hard and has sharp scales (like teeth) which can cause injury. Also do not use the blade of your knife to hit the shark. You should not make yourself easy prey. The shark 12. The marine environment prefers easy food and does not like to fight for it. Nevertheless, don't forget that the possibility of a shark attack on a diver, without previous provocation, is smaller than the probability of being struck by lightning. The majority of divers consider themselves very lucky if they have a chance to see a shark 13. ACUC International during their diving careers, and after you have done a few dives, you will also wish to see one.

12.2.2 Barracudas

This fish are very protective of their territory. They are not dangerous unless they are provoked. When they get nervous, the black marks on their bodies increase in size. If this happens, it is wise to stay a little distance from them so as not to upset them. The only risk can occur when you dive in water with poor visibility and carry shiny objects (chains, etc.). The barracuda has very poor eyesight, and it can confuse a shiny object for the scales of a fish. Avoid carrying shiny objects when diving in poor visibility water. Group of Barracudas 12.3 OTHER DANGEROUS MARINE FAUNA

The most dangerous and destructive animal below the surface of the water is man. Moray eels are definitely not dangerous unless you put your hand in their "house". The rest of the marine animals, wrongly considered dangerous, are only so if you bother them or, for example, if you accidentally step on them (for example, the sting ray, the stone fish, etc.).

A recreational diver, unless he is spear fishing, runs less assault risk by marine fauna than a person swimming at a beach. Page 35 ACUC - SCUBA DIVER

12. The marine environment (continued) 12.4 FRESH WATER

In fresh water, fish such as the Northern Pike and Muskellunge have been know to make passes at divers who come into their territory. These fish are attracted to shiny objects and in poor visibility water may strike out at the object. Large Mouth Bass will bang against you if you swim to near their eggs laid on rocks in calm areas. Zebra mussels are found on a lot of wrecks and other items lying on the bottom. These mussels have a very sharp shell that cuts through a wet suit like a razor if you brush against them.

12.5 CURRENTS

Always begin your dive swimming against the current and end your dive swimming with the current. This way, at the end of the dive when you are tired and have less air, it will be easier to return to the exit point from the water. Never try to fight a strong current that takes you away from your proposed exit point by swimming against it. Follow the current until it eases or swim with it diagonally to the exit point, getting progressively closer to shore. This will take you away from your proposed exit point but it will get you to shore where it will be easier to get back to the exit point by walking. When diving from a vessel, away from shore, where there is a strong current, there should always be a vessel prepared for the recovery of divers carried away by the current. Dive against the In addition, the vessel should use a float line. This line is about 100 ft. (30 m) long and is allowed current at the to float behind the anchored vessel for the divers to grab on to as the current carries them past. beginning of the Always carry a whistle to notify the vessel in case you have difficulties at the surface. The current dive is always weaker near the bottom. In addition, you can use rocks, weeds, etc., to help your progress. You could even stick your knife in the sand to help you advance. There is a type of diving known as "Drift Diving". This type of diving is practiced in many areas. It consists of a boat following the bubbles produced by the diver's exhaled air. This way, at the end of the dive, the boat is near the divers when they reach the surface. In this type of diving it is important that divers keep in a group as it is the only effective way to follow the bubbles from the surface. If you are interested in knowing more about Drift Diving or River Diving, ask your ACUC Instructor or the nearest Office about these specialty courses

12.6 THERMOCLINES

In colder water, there is a distinct water temperature change between the surface and the bottom. This change is known as a thermocline. The depth at which you reach the temperature change will vary depending on weather conditions in the surrounding area. As the water surface warms up from the heat of the sun, the warmer water rises towards the surface and the cold water sinks to the bottom. The water layers out so that a temperature change of 5 to 10 Deg. C. occurs in a matter of as little as 3 ft. (1 m). For the diver, this can be a real shock, especially if you are wearing a thin suit.

12.7 RESPECT FOR THE UNDERWATER ENVIRONMENT

It is the duty of all recreational divers to care for the underwater environment. An ACUC diver has a responsibility to not only care for it, but also to improve it in any way possible. You should know that the underwater environment is fragile, and that destroying even a tiny part of this environment can irreparably damage it, not only for us, but also for the future. We owe it to our children to ensure that this environment will be there for them to enjoy. Notify the authorities if you see, for example, illegal spear fishing (for example spear fishing that is being done in protected waters or spear fishing using Scuba equipment). If you see this and do not wish "to run into problems", write down specific details (photographs, videos, car license plates, vessel license numbers, etc.) and forward them to the ACUC National Office, who will study the information with their legal department, for possible legal action against the offenders. It is the responsibility of all of us to stop the damage that is being committed on our underwater environment, and therefore to our common interest.

If we do not do it ourselves, in co‑operation with the corresponding authorities, no one will do it for us.

If you are interested in the topic of Underwater Biology, request information from your ACUC Instructor or the closest Office on the Underwater Biology Specialty.

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Page 36 Introduction ACUC - SCUBA DIVER

1. Selecting the basic 13. ACUC INTERNATIONAL equipment 13.1 IDEOLOGY 2. Putting on the basic equipment The ideology of ACUC INTERNATIONAL is based on the promotion of diving as a recreational activity, in its teaching and its practice in a safe and fun way, in its learning by means of progressively more advanced courses and of specific specialty courses forming divers of high quality. ACUC 3. Using the basic prefers quality rather than quantity. ACUC also trains its divers so they acquire an ecologist mentality equipment and so that they care for the underwater environment. ACUC INTERNATIONAL is against any type of destructive diving activity. 4. Selecting the scuba equipment 13.2 HISTORY AND EXPERIENCE

5. Wearing the scuba For an up to date history, please see our web www.acuc.es equipment

6. Diving physiology 13.3 STRUCTURE

The International structure of ACUC consists of a North America main Office, located in Port Dover, 7. Using the scuba province of Ontario (Canada) and a European Main Office located in Madrid (Spain). equipment National Offices have been established in Countries where an official ACUC representative has been chosen and these National Offices report to the North American or European Office. Independent 8. Emergency ascents instructors, clubs, schools or diving centres affiliated with ACUC INTERNATIONAL in countries where there is no official representative also keep in touch with the North American or European Office. The certification levels are as follows (levels marked with an asterisk are optional 9. Underwater certifications): communications  Scuba Diver (*)  Open Water Diver 10. Decompression and  Advanced Diver different dive types  Rescue Diver  Divemaster  Assistant Instructor (*) 11. Rescue and first aid  Entry Level Instructor (*)  Open Water Instructor  Advanced Instructor 12. The marine environment  Instructor Trainer (*)  Instructor Trainer Evaluator

Talk with your Instructor as the levels can be modified periodically. 13. ACUC International

13.4 ADVANCED PROGRAMS AND SPECIALTIES

ACUC INTERNATIONAL has a large number of advanced and specialty programs available. One of the objectives of ACUC INTERNATIONAL is to offer all of its members the opportunity to learn more about the areas of scuba diving that interest them, as well as help them in their personal development so that they can attain professional teaching levels, if they are interested. Following is a list of ACUC specialty courses:

 Cave Diver  Cavern Diver  Deep Diver  Dive Controller  Dive Guide  Drift Diver  Dry Suit Diver  Equipment Maintenance  First Aid  Ice Diver  Night Diver  Nitrox Basic Diver Page 37 ACUC - SCUBA DIVER

13. ACUC international (continued)  Nitrox Advanced Diver  Nitrox Mixer  Rebreather Diver  Sidemount Diver  Teaching Assistant  Underwater Digital Photography  Underwater Biology  Wreck Diver

Please Note that some specialties might not be available in some countries.

13.5 PROCEDURES FOR OBTAINING A LOST CERTIFICATION CARD

For up to date information, please see our web www.acuc.es

13.6 COURTESY TO OTHER ORGANIZATIONS

ACUC INTERNATIONAL believes that diversity improves quality. Therefore, we request that all of our members respect and show courtesy to those divers who possess certifications from other organizations. ACUC INTERNATIONAL maintains an Open Door Policy to co‑operation and dialogue with those organizations who wish to cooperate with us. We aim to advance the quality and the safety in the teaching and practice of recreational diving and in the respect of the underwater ecology and life.

13.7 ACUC INTERNATIONAL AND THE RSTC

ACUC INTERNATIONAL is a member of the Canadian and European RSTC (Recreational Scuba Training Council). The RSTC is an umbrella group that gathers the most important certifying agencies from across the world to standardize such things as the minimum training standards for divers and instructors. Because of this, ACUC recognizes and is recognized by most international agencies. For more information please see www.wrstc.com

13.8 THE ACUC DIVER ACCIDENT INSURANCE

To dive in certain countries it is mandatory to have divers insurance. All ACUC divers can, if they choose, through ACUC, obtain an international insurance for the practice of recreational diving. For more information, please contact your nearest ACUC Office.

13.9 BEHAVIOUR OF AN ACUC DIVER

The ACUC INTERNATIONAL certification is highly regarded in the world of recreational diving, mainly due to the proficiency and concern for the environment of those who are certified ACUC. We intend to keep it that way even if this means growing slower. We want quality rather than quantity.

As an ACUC diver, we request that you always use your common sense, observe all safety rules, respect other divers, behave ethically when on group dives, never cause any destruction of our underwater world by respecting the fragile underwater ecology and pass this way of acting and thinking on to all of those with whom you interact when diving.

Your Instructor offers you a certification which you can show with pride anywhere in the world. Please do not shame him/her. We would prefer, if you do not agree with this, for you to obtain your certification through another agency. We request that you read the following "ACUC Divers Commitment".

13.10 DIVERS COMMITMENT

We remind all those who wish to obtain an ACUC certification that the commitments of our Organization, and therefore any one who issues or obtains our certification, are:

Page 38 ACUC - SCUBA DIVER

13. ACUC international (continued)  To respect the Underwater Ecology, and when diving, leave only bubbles and take only photos and/or videos. Never damage any underwater organism, be it fish, crustacean or coral.  To always respect the safety rules and use common sense when diving, staying within or equal to the safety margins, but never exceeding the depth and time limits on the decompression tables.  To never dive after consuming alcoholic beverages or taking drugs. Always use some type of buoyancy control device, pressure gauge, depth gauge and/or computer, in addition to the rest of the normal equipment, including an alternate air source (octopus system).  To never practice any type of destructive diving and never attempt dives that require specialized training (such as cavern diving, deep diving, etc.) until you have received the proper training.

An ACUC diver must always show by their actions as well as their word the high standard of Ecology Conservation, underwater safety, respect for other divers of other organizations and their general behaviour that are the cornerstones of the foundation of ACUC INTERNATIONAL.

It is the responsibility of the Instructor to assure that only candidates that agree with this ideology obtain one of our certifications. The student and the Instructor should understand that if the student does not respect these principles, it could cause the possible cancellation of the certification of the Instructor, who would lose the right to renew his certification, until it was decided by the Executive Board of ACUC INTERNATIONAL, and that such suspension could be extended indefinitely. Please help us to maintain our high standards.

Finally, if you wish to see the ACUC standards for the different courses, you can do so in our web www.acuc.es

Press here to go to the end of the manual IMPORTANT NOTICE

We recommend that you note the information regarding your Instructor as well as any other relevant data about this course and your certification. In a safe place Ask your Instructor to show you his/her ACUC Certification Card and ensure is in “Active” Status. See the “Consumer Info” section in the ACUC web www.acuc.es

THANK YOU FOR CHOOSING ACUC

VISIT OUR WEB WWW.ACUC.ES AND ANSWER OUR QUALITY CONTROL QUESTIONNAIRE

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