1. Self Contained Underwater Breathing Apparatus
SCUBA Diving
Self Contained Underwater Breathing Apparatus

2. PADI Open Water Course
Course Requirements must be completed for certification
Knowledge development- completed before pool
Read PADI manual, complete worksheet, Video and quiz for all 5 chapters
Pass PADI final exam
2 pool practice sessions
4 ocean dives, 2 per day

3. PADI Section 1
Being a Diver 1

4. Water Pressure and Air Volume
At Sea level the weight of the atmosphere above us exerts a pressure of 1 Atmosphere (14.7 psi) on us
Water is heavier than air so it only takes 33 feet of water to equal 1 ATM of pressure
At 33 feet under water you are at a pressure of 2 ATM, 1 from the atmosphere and 1 from the water above you
Pressure increases by 1 ATM every 33 feet(10 meters)

5. Water Pressure and Air volume

6. Depth, Pressure and air Density

7. Depth, Pressure and Surface Equivalent

8. Increasing Pressure and Body Air Spaces
Body air spaces include Lungs, inner ear, sinuses and mask and possibly teeth fillings
To equalize your ears and sinuses pinch your nose and blow gently against it
To equalize your mask exhale out your nose adding air to the mask
If you cannot equalize stop your descent immediately, signal your buddy or instructor
An unequalized air space is called a squeeze

9. Equalization of Air Spaces
Ascend slightly until discomfort passes and try again, after you equalize descend slower and equalize more often
Continuing to descend with unequalized air spaces can lead to dammage to the eardrum
An unequalized mask can cause bruising around the eyes
If you cannot equalize stop the dive

10. Equalization of Air Spaces
Never attempt a forceful or extended equalization
Use short gentle, frequent equalizations
Never dive with a cold or allergy, congestion can block sinuses and air passages
Cold medications can wear off during a dive
Never use ear plugs or goggles while diving

11. Equalization of Air Spaces
Lung equalization is accomplished by normal continuous breathing
Skin (Breath Hold) Diving poses special problems, do not descend after exhaling or breath hold diving deeper than 200 feet
Do not Dive with lung congestion which can trap air

12. Effects of Decreasing Pressure on Air Spaces
Air pressure decreases during ascent
Expanding air must exit the body
This happens naturally in your ears, sinuses and mask
Expanding air in your lungs is most important
Normal breathing while ascending will release expanding air from your lungs
Never Hold your breath While on SCUBA

13. Effects of Decreasing Pressure on Air Spaces
Most Important Rule in SCUBA is Always Breath
Lung over expansion can happen in as little as 3 feet, a slight pressure change
Lung over expansion injuries are difficult to treat and can cause paralysis and death by forcing air into the blood stream and chest cavity
Anytime the regulator is not in your mouth exhale a slow steady stream of bubbles

14. Effects of decreasing Pressure on Air Spaces
Reverse Blocks result when expanding air becomes trapped in a body air space
Reverse blocks can occur when diving with a cold or allergy or using cold medicine
Gas can form in the stomach or intestine and may take time to pass
A tooth squeeze is rare but can happen if air is trapped under a filling
If you feel discomfort on ascent, stop descend a few feet, give the air time to escape and ascend slower

15. Breathing Underwater
Pressure increases with depth and decreases air volume
Density of air increases as volume decreases
Each breath fills the same lung volume so more air is needed to fill each breath
The deeper you are the faster you use air
A tank of air that lasts 1 hour at 0 feet will last ½ hour at 33 feet (10 meters)

16. Buoyancy
Buoyancy of an object is dependent on the weight of the object compared to the weight of the water displaced by the object
Three types of Buoyancy positive, neutral and negative
The Buoyancy compensator device allows us to change our buoyancy as needed
The weight system allows us to overcome the bodies natural Buoyancy

17. SCUBA Equipment

18. PADI Section 2
Being a Diver 2

19. Section 2
Water is 800 times denser than air which causes many differences between terrertrial and aquatic worlds
Magnification- underwater everything looks 1/3 larger which causes it to look closer
Color loss occurs as you go deeper, red, yellow and orange penetrate the least, Blue, green and purple penetrate the deepest
Underwater sound travels 4x faster and greater distances, we cannot tell the direction it is coming from

20. Swimming and Moving
Because of waters density streamlining is very important to reduce drag and save energy
Increasing your speed while swimming requires 4 times more energy and air consumption
Trim your body position so feet and head are approximately level by placing the correct amount of weight and appropriate position

21. Staying Warm
Water absorbs heat 20 times faster than air, you can chill rapidly in water 86 degrees
Hypothermia is a serious condition, uncontrolled shivering means end the dive and exit the water immediately
An appropriate exposure suit, wet or dry suit will keep you comfortable while diving
Wet suits work by absorbing water which your body heats and retaining that water so you do not have to reheat new water

22. Wet Suits

23. Dry Suits

24. Breathing Effectively Underwater
Because of the increased density of the air we breath while Diving slow deep breathing requires less effort
Deep breathing is more efficient at exchanging gases O2 and CO2 in our lungs
Deeper breathing minimizes the dead air spaces in our throat and equipment
Airway control is the skill of breathing with residual water in our regulator or snorkel without drawing any into your throat

25. Managing Your Air Supply
On shallow dives air supply is usually the limiting factor
Plan or returning to the boat with 500 psi remaining in your Tank as a reserve
A safety stop at 15 ft for 3-5 min requires 300 psi (totals 800psi) reserve and safety
If your starting pressure is 3000 psi minus 800psi you have 2200 psi to dive with so 1100 psi out and 1100 back

26. Managing Your Air cont.
Plan your air management based on who has the least air
On deeper dives (ship wrecks) plan on leaving the bottom with 1000 psi in tank
As you ascend to shallower depth you use air at a much slower rate
“Do not risk running out of air underwater” ascend where you are and swim on surface

27. Deep Wreck Diving

28. Buddy System Number two rule in SCUBA Diving “Never Dive Alone”
Buddy System- Two or more divers working together for convenience, safety and fun
Plan the dive and then Dive the Plan
Agree on entry and exit points, course to follow, depth and time limits, signals and communication, turn around point, who leads and who follows, separation procedures

29. Buddy system cont.
Predive safety check- begin(BC)- with(weights) review(releases) – and(air)- friend(final OK)
Buddy separation procedures- look for no more than one minute 360 degrees on bottom then surface and reunite on the surface and descend together
On deep shipwreck meet at anchor/ascent line
It is Your responsibility to stay together

30. Buddy System

31. Buddy System

32. PADI Section 3
Being a diver 3

33. Section 3
Dive environments and conditions vary world wide and by season and assessing these can affect your dive plans
Besides season water depth can affect temperature, the deeper you go the colder it can get, wear an appropriate exposure suit
Visibility can range from 0 to 200 feet and is affected by water movement, weather, plankton and bottom composition

34. Water Movement
Two types of water movement affect diving, waves and current
The stronger the wind the larger the waves, smaller waves 1-3 feet seldom affect diving but larger waves require more experience and may prevent diving
Currents are a result of waves, tides, heating and cooling water and the earths rotation
Begin your dive into or against the current, when you head back the current will assist you

35. Water Movement cont.
Currents tend to be strongest at the surface, swim along the bottom where the current is generally weaker
If you miss your exit point or boat swim across the current rather than directly into it, there is generally a trail (tag) line off the back of the boat
If you cannot get to the boat, establish buoyancy, fill your BC or drop weights and signal the boat to pick you up

36. Trail ( Tag ) Line

37. Diving in Current

38. Dive Boat

39. Descending Mooring/ Anchor Line

40. Bottom Composition
Bottom composition types-silt/mud, sand, rock, coral, vegetation
Bottom composition may be multiple types at a dive site
Avoiding bottom contact keeps visibility clearer and avoids hazards like cuts or scrapes
Aquatic organisms may be fragile and damaged if touched
Stay neutrally buoyant and only touch insensitive bottoms if necessary

41. Assessing Conditions
You are responsible for your own safety and you will be part of the final decision on making the dive
One of the skills you will develop as a diver is assessing conditions weather, water motion, visibility, reports online and reports from other divers
An area orientation dive will help you become familiar with local conditions, hazards and points of interest

42. Diving Limits
Dive within your personal physical limits and scope of training
Failure to do so can lead to incidents and accidents
Risks are not always obvious
Exceeding limits give false security as having “got away with it”
Some anxiety about the dive can affect focus and miss potential problems

43. Aquatic life
Observing aquatic life is one of the main attractions of diving but some pose potential problems, interactions should be passive.
Organisms that sting/puncture- jellyfish, portuguese man-o-war, lion and scorpion fish, stingrays, sea urchins, cone shells.
Organisms that bite-moray eels, trigger fish, sharks, barracuda and other fish, snakes, octopus, clawed lobster and crabs

44. Aquatic Life cont.
Passive and active interactions, generally passively observing marine life is best for all
Active interactions when the animal initiates the interaction is reasonable
Feeding marine life can create problems, better left to professionals

45. Marine Life

46. Shark Feeding

47. Aquatic Animal Injuries
Be familiar with hazardous organisms in the local environment
Avoid wearing shiny dangling jewelry
Watch where you put your hands, knees and feet, avoid bottom contact if possible
Be cautious in murky water, animal may mistake a diver for prey in poor visibility
Usually very pretty or very ugly organisms who do not try to escape are dangerous

48. Aquatic Animal Injuries
Even dead organisms or detached body parts can still sting, puncture
Be prepared to provide first aid and CPR
Use vinegar on jellyfish and fire coral stings
Immerse stings from fish spines in hot 120 degree water min
Remove sea urchin spines with forceps without breaking them, otherwise for medical personnel

49. Aquatic Animal Injuries
Treat bites by controlling bleeding, bandaging
Seek emergency medical care for bites that result in severe reactions, or large ones that do not respond to treatment
You can learn more in the PADI Rescue Diver course and the Emergency first Response primary Care (CPR) and Secondary Care (First Aid) courses

50. Lion Fish

51. Portuguese Man o war

52. Fire Coral

53. Stone Fish

54. Sea Urchin

55. Shore Diving Most environments offer shore diving
Put on your equipment except your mask, snorkel and fins
Put mask on just before entering water and don you fins in waist to chest deep water
Leave BC empty to keep weight on your feet
As you enter surf turn sideways and bend knees to brace yourself against wave

56. Shore Diving cont.
Surge is the back and forth motion of the wave underwater, bigger waves have deeper surge, Dive deeper below the surge
Undertow is the wave running back down the slope of the beach, may undermine your footing, if you fall just crawl out
Rip currents form from water pushed over a sandbar and move back through available openings, you can see a break in the incoming waves

57. Rip Currents

58. Rip Current

59. Boat Diving Most diving is done from boats to avoid long surface swims
You can dive from large charter boats or something as small as a kayak
Use a Gear bag to organize your equipment, bring clothes, beverages, snacks
Seasickness can be addressed with motion sickness medicine, look at the horizon, keep the wind in your face

60. Boat Terminology Bow – front of boat (forward)
Stern- back of boat (aft)
Starboard- right side of boat
Port- left side of boat
Head- Toilet Facilities
Galley- kitchen
Bridge- where the boat is driven from
Swim Platform-extension from stern for entering and exiting water

61. Dive Boats

62. Dive Boats

63. Dive Boat Ladder

64. Boat Diving Entry Giant Stride entry from platform
BC jacket 1/3 full air
Real toes up to edge of platform
Check that area is clear then Look straight out
Right hand on mask/regulator left hand on releases
Hoses for SPG and Alternate Regulator collected inside elbows
Pick up leading edge of fin as you step

65. Boat Diving Exits Follow directions of divemaster on boat
Hang onto tag line on surface until it is your turn, stay clear of ladder
Remove fins while holding tag line/ ladder and hand up to divemaster
Both hands and feet on ladder, one step at a time/ two feet one step
Keep mask on and regulator in mouth in case you fall back in

66. Problem Management
SCUBA diving comes with some risks and potential problems from being in water and breathing compressed air
Your knowledge and training will help you to manage and avoid problems and control risks
Additional diver training and experience improves your ability to manage problems
PADI advanced open water course gives you additional training under supervision

67. Problem management
PADI rescue diver course covers dive emergency training with hands on practice
Emergency first response primary and secondary care courses teach you CPR and First Aid
PADI Emergency Oxygen provider qualifies you to administer Oxygen in medical emergencies

68. Problem Management Assisting Divers at Surface
Most Diver in distress problems occur at the surface
Dive within your limits
Relax while you dive
Plan your use of air
Establish buoyancy
Stop, Think, Act
Asking for Help when you have a small problem avoids a big problem

69. Problem Management Assisting Divers
Free flowing regulator- hold regulator up to lips and sip air from regulator, let excess air escape, head to surface
Entanglement- stop, think work calmly to free yourself, avoid turning or twisting, use cutting tool if necessary, you may slip out of SCUBA kit to free it
Overexertion- most common underwater problem, pace yourself breath slowly/ deeply

70. Running Low On/ Out of Air underwater
1 Make a normal ascent- cylinder is not completely empty, as you ascend you get more air from your cylinder
2 Ascend using alternate air source- Best choice when an alternate air source is available, stay close to your buddy

71. Running Low On/ Out of Air underwater
3 Controlled Emergency Swimming Ascent- completely out of air and no deeper than 30 ft. Buddy is too far away. Look up and swim to the surface making an aaah sound to exhale expanding gas. All gear stays in place, control your rate of ascent
4 Buoyant Emergency Ascent- deeper than 30 ft same procedure as emergency swimming ascent except drop your weight belt, near surface flare arms and legs to slow ascent

72. Problem Management Assisting Divers
Unresponsive Diver at surface- establish buoyancy for both divers, check breathing and begin rescue breaths while towing, call for help from boat
Unresponsive Diver underwater- make victim buoyant, hold regulator in mouth if already there, swim victim to surface, ascend at a safe rate, check breathing at surface

73. Dive Flags