diving medical officer handbook · 2017. 9. 15. · basic diving physics 82 air diving...

DIVING MEDICAL OFFICER HANDBOOK

Compiled by LT Brad Kinney UMO (April 2016)

3

TABLE OF CONTENTS

DIVING MEDICINE EMERGENT MANAGEMENT 5

COMMUNICATIONS 5 AIR GAS EMBOLISM 7 DECOMPRESSION SICKNESS 9 CHAMBER OPERATIONS 13

RECOMPRESSION CONSIDERATIONS 13 TREATMENT TABLES 18 AIR TREATMENT TABLES 27 SYMPTOM RECURRENCE 29 POST-TREATMENT CONSIDERATIONS 30 HYPERBARIC OXYGEN THERAPY 32 CHAMBER LIFE SUPPORT CONSIDERATIONS 33

MISCELLANEOUS DIVE MEDICINE 42

DIVE PHYSIOLOGY 42 BASIC DIVE MEDICINE 46 EAR AND SINUS PROBLEMS 48 MARINE POISONING AND ENVENOMATION 50 BAD GAS 53 VERTIGO AND DIVING 54 NEUROLOGICAL EXAM 56 ENVIRONMENTAL PLANNING 67 THERMAL CONSIDERATIONS 70 ALTITUDE CONSIDERATIONS 75

EMERGENCY KITS 78

CHAMBER EMERGENCY KITS 78 DMO MEDICAL BAG 80 BRAD’S DMO BAG 81

DIVING OPERATIONS BASIC DIVING PHYSICS 82 AIR DIVING NO-DECOMPRESSION TABLE 83 AIR DIVING RNT TABLE 84 REPET DIVES 85 DIVER AIR QUALITY 87 DIVE PLANNING 91 UNDERWATER SIGNALING 99

SOURCES 103

5

EMERGENT MANAGEMENT

COMMUNICATIONS

Table 1: Important Comms.

1

DIVERS ALERT NETWORK (DAN) Emergency Hotline +1-919-684-9111

Medical Information +1-919-684-2948 Table 2: DAN Contact Info.

2

1 DIVEMAN, Appendix 1C.

2 DAN Dive and Travel Medical Guide.

6

Figure 1: Emergency Checklist.

3

3 DIVEMAN, Figure 6-22.

7

AIR GAS EMBOLISM

Pulmonary Overinflation Syndrome Condition Symptoms Signs

Arterial Gas Embolism

Seizure (focal or general), unconsciousness, confusion, headache, visual disturbances, bloody sputum (rare)

Hemiplegia, monoplegia, altered level of consciousness, blindness, visual motor deficit, focal motor or sensory loss

Mediastinal-subcutaneous emphysema

Substernal pain, “brassy voice,” neck swelling, dyspnea

Subcutaneous crepitus, gas patterns on radiographs of mediastinum and neck

Pneumothorax Chest pain, dyspnea Loss of breath sounds, hyperresonant chest percussion, tracheal shift

Table 3: POIS.4

Figure 2: POIS continued.

5

4 Wilderness Medicine, Table 77-4, page 1534.


8

Figure 3: AGE and Severe DCS Algorithm.

6


9

DECOMPRESSION SICKNESS

Common Symptoms and Signs of Decompression Sickness

Condition Symptoms Signs MSK DCS (bends)

Severe joint pain, single or multiple joints involved, paresthesia or dysesthesia about joint, lymphedema (uncommon)

Tenderness, which may be temporarily relieved by local pressure with blood pressure cuff; pain worsened by movement of joint

Neuro DCS (spinal cord)

Back pain, girdling abdominal pain, extremity heaviness or weakness, paralysis, paresthesia of extremities, fecal incontinence, urine retention

Hyperesthesia or hypoesthesia, paresis, anal sphincter weakness, loss of bulbocavernosus reflex, urinary bladder distention

Neuro DCS (brain)

Visual loss, scotomata, headache, dysphasia, confusion

Visual field deficit, spotty motor or sensory deficits, disorientation or mental dullness

Fatigue Profound generalized heaviness or fatigue

May precede signs of other forms

Cutaneous Intense pruritis No visible signs, mottling, local or generalized hyperemia or marbled skin (cutis marmorata)

Chokes Dyspnea, substernal pain that is worsened on deep inhalation, nonproductive cough

Cyanosis, tachypnea, tachycardia

Vasomotor DCS (decompression shock)

Weakness, sweating, unconsciousness

Hypotension, tachycardia, pallor, mottling, hemoconcentration, decreased urine output

Inner Ear (vestibular DCS)

Tinnitus, vertigo, nausea, vomiting Ataxia, possible nystagmus and positive Romberg, acute sensorineural hearing loss

Table 4: DCS Signs and Symptoms.7

7 Wilderness Medicine, Table 77-5, page 1539.

10

Differentiating Features between Disorders of the Spine and Spinal Cord DCS

Favoring Spine Disorder Favoring DCS History -Prior lumbar or cervical

radiculopathy, spine surgery -Documented chronic sensory or motor deficits

-Absence of prior spine involvement -No prior neurologic deficits (before dive)

Symptom onset Prior to or during the dive (before ascent)

Post dive

Diving exposure Benign: shallow depth, short duration, within No-D limits

Provocative: deep depth, long duration, at or beyond No-D limit

Physical Pain Localized to specific dermatome,

usually unilateral, commonly cervical or lumbar

Pain localized to a joint, bilateral, or involving multiple dermatomes, often trunk or abdomen

Paresthesia anesthesia

Dermatomal, usually cervical or lumbar, usually unilateral

Involves multiple cord levels, often bilateral

Cerebral/cerebellar findings

Absent May be present (with accompanying AGE)

Tendon reflexes Depressed or absent at level of involvement, often unilateral

Hyperreflexic, often bilateral

CT/MRI Disc herniation, narrowed neuroforamina, no cord lesions demonstrated

Cord lesion demonstrated

Table 5: Spinal Disorders vs. Spinal Cord DCS.8

8 Bove and Davis, Table 23-1, page 465.

11

Figure 4: Various DCS Considerations.

9

9 DIVEMAN, Section 20-3.

12

Figure 5: Type I DCS Algorithm.10

10

DIVEMAN, Figure 20-2.

13

CHAMBER OPERATIONS

RECOMPRESSION CONSIDERATIONS

Figure 6: Recompression Rules.

11

11

DIVEMAN, Table 20-1.

14

Table 6: Chamber Requirements.

12

Table 7: Chamber Support Levels.

13

12

DIVEMAN, Table 6-1. 13

DIVEMAN, Table 6-2.

15

Figure 7: Chamber Log.

14

14

DIVEMAN, Section 5-5.

16

Table 8: Tender Breathing Requirements.

15

Table 9: Chamber Exposure Times.

16

15



17

Table 10: Extended Surface Interval and Type I DCS.

17

Table 11: Asymptomatic Omitted Decompression.

18

17


DIVEMAN, Table 9-3.

18

TREATMENT TABLES

Figure 8: TT5.

19

Figure 9: TT5 Indications.

20

19

DIVEMAN, Figure 20-4. 20

DIVEMAN, Section 20-5.2.

19

Figure 10: TT6.

21


22

21



20

Figure 12: TT6A.

23

Figure 13: TT6A Indications.

24

23



21

Figure 14: TT4.

25


26

25



22

Figure 16: TT7.

27

Figure 17: TT7 Indications and Considerations.

28

27


DIVEMAN, Section 20-5.6 (pages 22-24).

25

Figure 18: TT8.

29


30

29



26

Figure 20: TT9.

31


32

31



27

AIR TREATMENT TABLES

Figure 22: Air TT1A.

33

Figure 23: Air TT1A Indications.

34

33



28

Figure 24: Air TT2A.

35

Figure 25: Air TT3.

36

35



29

SYMPTOM RECURRENCE

Figure 26: Symptom Recurrence Algorithm.

37

37


30

POST-TREATMENT CONSIDERATIONS

Figure 27: Post-Treatment Considerations (pages 30-31).

38

38

DIVEMAN, Section 20-8.

32

HYPERBARIC OXYGEN THERAPY

Table 12: HBO Therapy.

39

39


33

CHAMBER LIFE SUPPORT CONSIDERATIONS

Figure 28: Chamber Life Support Considerations.

40

40

DIVEMAN, Section 20-7 (pages 33-41).

42

MISCELLANEOUS DIVE MEDICINE

DIVE PHYSIOLOGY

Figure 29: Lung Volumes.

41

41


43

Figure 30: Oxygen Consumption Rates.

42

42


44

Figure 31: Saturation of Tissues.

43

43


45

Figure 32: Desaturation of Tissues.

44

44


46

BASIC DIVE MEDICINE

Differential Diagnosis of Conditions Presenting After Surfacing by Time of Onset

<2 min 2-10 min >10 min DCS DCS DCS

Hypothermia Hypothermia Hypothermia IEBT IEBT IEBT CAGE CAGE

Pneumothorax Pneumothorax Pneumomediastinum Pneumomediastinum Alternobaric Vertigo

Hypercapnia Hypoxia

Oxygen Toxicity CO Poisoning

Table 13: Dive Differential Diagnoses.45

Causes of Unconsciousness in Divers Breath-Hold Diving

Underwater hypoxemia after hyperventilation before the dive “shallow-water blackout”

Near drowning

Compressed Gas Equipment

Hypoxic breathing gas

Contaminated breathing gas (such as carbon monoxide)

Equipment failure or exhaustion of breathing gas

Near drowning

Inert gas narcosis

Oxygen toxicity

Pulmonary barotrauma with arterial gas embolism

Rebreathing Equipment

Carbon dioxide toxicity

Oxygen poisoning Table 14: Unconscious Divers.

46

45

Bove and Davis, Table 18-4, page 359. 46

Wilderness Medicine, Box 77-5, page 1538.

47

Potential Medical Problems Associated with Each Phase of a 130-fsw SCUBA Dive on Air

Descent On Bottom Ascent After Surfacing Aural and Sinus Barotrauma

Most likely injury

Impossible except for delayed perilymph fistula

Most likely injury

Impossible, except for delayed perilymph fistula

Hypercapnia Unlikely Unlikely unless: -CO2 is present in air -Regulator resistance is extensive -Skip breathing is used

Unlikely Not possible

CO Poisoning Unlikely -Inadequate time for uptake -Increased PO2 protects

Unlikely -Increased PO2 protects

Most likely time -Adequate time for uptake -Loss of PO2 protection

Unlikely

Alternobaric Vertigo Possible Possible immediately after arrival on bottom

Most likely time

Within 1st 2 minutes only

Nitrogen Narcosis Slight -Aggravated if descent rapid

Slight None None

DCS Not possible Not possible Rare Most likely time Occupational Injury Possible Most likely time Possible Possible CAGE Not possible Not possible Possible in late

stages Possible -Onset of symptoms within 10 minutes of surfacing

Pneumothorax, Pneumomediastinum

Not possible Rare -Usually associated with ditch-and-don exercises

Possible in late stages

Possible -Onset of symptoms within 10 minutes of surfacing

Table 15: Dive Diagnoses Presentations.47

47

Bove and Davis, Table 18-5, page 362.

48

EAR AND SINUS PROBLEMS

Figure 33: Sinuses.

48

Figure 34: Ear Anatomy.

49

48



49

Teed Grading System for Middle Ear Barotrauma Grade Description

0 Symptoms without otologic findings 1 Erythema and mild retraction of the TM 2 Erythema of the TM with mild or spotty hemorrhage within the TM 3 Gross hemorrhage throughout the TM 4 Grade 3 changes plus gross hemorrhage within the middle ear

(hemotympanum) 5 Free blood in middle ear plus perforation of the TM

Table 16: TEED Grading.50

Characteristics of Inner Ear Barotrauma and Inner

Ear DCS IEBT IEDCS Time of symptom onset During compression

(associated with MEBT). During or shortly after decompression.

Dive characteristics -Dives not requiring staged decompression. -Can occur during compression phase of deeper dives. -Dives with rapid descents. -Reported cases associated with air diving – can probably occur with helium diving.

-Dives requiring staged decompression. -Dives without proper, staged ascents. -More common during decompression from helium dives – can occur with air diving.

Possible associated symptoms

-Difficulty with ear clearing and/or ear pain or drainage – frequent. -May have a history of preexisting nasal, sinus, or middle ear disease.

-None or other symptoms of decompression sickness.

Possible associated physical findings

Signs of middle ear barotrauma – frequent.

None or other symptoms of decompression sickness.

Table 17: IEBT vs. IEDCS.51

50

Wilderness Medicine, Table 77-3, page 1529. 51


50

MARINE POISONING AND ENVENOMATION

Marine Toxin Diseases Disease Ciguatera

poisoning Scombroid poisoning

Puffer fish poisoning

PSP paralytic shellfish poisoning

DSP diarrheic shellfish poisoning

ASP amnesic shellfish poisoning

NSP neurotoxic shellfish poisoning

Vector Carnivorous reef fish (barracuda, grouper, moray eel, parrot fish, red snapper, surgeon fish, trigger fish, amberjack, wrass, mullet)

Scombroid fish (tuna, mackerel, skipjack, bonito)

Puffer fish (served as Fugu in Japanese restaurants)

Shellfish Shellfish Shellfish Shellfish

Organism Dinoflagellate Surface bacteria ? bacteria Red tide dinoflagellate

Red tide dinoflagellate



Distribution Worldwide tropical and subtropical

Worldwide Worldwide Worldwide temperate

Worldwide temperate

North America Gulf of Mexico, New Zealand

Incubation Hours Minutes-hours 5-30 minutes Hours Hours Days Duration Months-years <24 hours Days Days Days Years Days Symptoms GI, neuro Cutaneous Neuro

(respiratory paralysis)

Neuro (respiratory paralysis)

GI Neuro GI, Neuro

Mortality <1% 0% 60% 1-14% 0% 3% 0% Treatment Supportive,

mannitol Antihistamines, H2-blockers

Supportive (respiratory)

Supportive (respiratory)

Supportive Supportive Supportive

Prevention (Avoid)

Avoid large carnivorous fish

Poorly preserved fish

Puffer fish Shellfish Shellfish Shellfish Shellfish

Table 18: Marine Toxin Diseases.52

52

http://www.the-travel-doctor.com/seafoodpoisoning.htm.

51

Figure 35: Marine Envenomation Algorithm.53

53

Wilderness Medicine, Figure 80-104, page 1627.

52

Algorithmic approach to marine envenomation. *A gaping laceration, particularly of the lower extremity, with cyanotic edges suggests a stingray wound. Multiple punctures in an erratic pattern with or without purple discoloration or retained fragments are typical of a sea urchin sting. One to eight (usually two) fang marks are usually present after a sea snake bite. A single ischemic puncture wound with an erythematous halo and rapid swelling suggests scorpionfish envenomation. Blisters often accompany a lionfish sting. Painless punctures with paralysis suggest the bite of a blue-ringed octopus; the site of a cone snail sting is punctate, painful, and ischemic in appearance. †Wheal and flare reactions are nonspecific. Rapid (within 24 hours) onset of skin necrosis suggests an anemone sting. “Tentacle prints” with cross-hatching or a frosted appearance after application of aluminum-based salts suggest box-jellyfish (Chironex fleckeri) envenomation. Ocular or intraoral lesions may be caused by fragmented hydroids or coelenterate tentacles. An allergic reaction must be treated promptly. ‡Sea snake venom causes weakness, respiratory paralysis, myoglobinuria, myalgias, blurred vision, vomiting, and dysphagia. The blue-ringed octopus injects tetrodotoxin, which causes rapid neuromuscular paralysis. §As soon as possible, venom should be sequestered locally with a proximal venous-lymphatic occlusive band of constriction, or (preferably) by the pressure-immobilization technique, in which a cloth pad is compressed directly over the wound by an elastic wrap that should encompass the entire extremity at a pressure of 9.33 kPa (70 mmHg) or less. Incision and suction are not recommended. ¶Early ventilatory support has the greatest influence on outcome. The minimal initial dose of sea snake antivenom is one to three vials; up to 10 vials may be required. ǁThe wounds range from large lacerations (stingrays) to minute punctures (stonefish). Persistent pain after immersion in hot water suggests a scorpionfish or stonefish sting or a retained fragment of a spine. The puncture site can sometimes be identified by forcefully injecting 1% to 2% lidocaine or another local anesthetic agent without epinephrine near the wound and observing the egress of fluid. Do not attempt to crush the spines of sea urchins if they are present in the wound. Spine dye from already-extracted sea urchin spines will disappear (be absorbed) in 24 to 36 hours. **The initial dose of stonefish antivenom is one vial per two puncture wounds. ††The antibiotics chosen should cover Staphylococcus, Streptococcus, and microbes of marine origin, such as Vibrio. ‡‡Acetic acid (5%; i.e., vinegar) is a good all-purpose decontaminant and is mandated for the sting from a box-jellyfish. Alternatives, depending on the geographic region and indigenous jellyfish species, include isopropryl alcohol, bicarbonate (baking soda), ammonia, papain, and preparations containing these agents. Hot (45° C or 113° C; usually, heated water) application may be effective for relieving pain. §§The initial dose of box-jellyfish antivenom is one ampule IV or three ampules IM. ¶¶If inflammation is severe, steroids should be given systematically (beginning with at least 60 to 100mg of prednisone or its equivalent), and the dose should be tapered over a period of 10 to 14 days. ǁǁAn alternative is to apply and remove commercial facial peel materials. ***An alternative is to apply and remove commercial facial peel materials, followed by topical soaks of 30mL of 5% acetic acid (vinegar) diluted in 1 L of water for 15 to 30 minutes several times a day until the lesions begin to resolve. Anticipate surface desquamation in 3 to 6 weeks.54

54

Wilderness Medicine, Figure 80-104, page 1627.

53

BAD GAS

Table 19: Common Problems with Breathing Gas Under Pressure.

55

55

http://books.publications.chestnet.org/data/Books/PULM/chapter41-t02.png.

54

VERTIGO AND DIVING

Causes of Vertigo in Divers Decompression Sickness Hypoxia Hypercarbia Nitrogen Narcosis Seasickness Alcoholic Hangovers Sensory Deprivation Hyperventilation Impure Breathing Gas Unequal Caloric Stimulation Difficulties with middle ear pressure equalization

Table 20: Vertigo in Divers.56

Differential Diagnosis of Central and Peripheral Vertigo in Diving

Peripheral Central Symptoms Generally intense with nausea and

vomiting. Generally affected by head movement; one head position may be critical

Only slightly responsive to head movement

Spontaneous Nystagmus

Horizontal or rotatory, never vertical. Suppresses with visual fixation. Gaze direction dependent. Always conjugate.

All forms possible. Unchanged or enhanced by visual fixation. May depend on gaze direction. May be disconjugate.

Positional Nystagmus 2-10 sec latency period. Short-lived. Positive when affected ear is positioned downward. Direction fixed. Response fatigues on repeat testing.

No latency. Generally persists. Positive when either ear is positioned downward. Direction changing. Response does not fatigue.

Saccadic and smooth eye pursuit

Normal Very infrequent

Associated Auditory findings

Frequent Very Infrequent

Neuro Exam Results Normal* Abnormal *Peripheral labyrinthine lesion in DCS and CAGE may be associated with an abnormal result on neuro exam

Table 21: Central vs. Peripheral Vertigo.57

56

Bove and Davis, Table 22-1, page 438. 57


55

Differential Diagnosis of Vertigo after Surfacing ABV IEBT DCS CAGE Onset Within 2 min Anytime Anytime Within 10 min Duration Usually

short, <10 min

Persistent Persistent Persistent

Associated Neuro Findings

Absent* Absent Possible Common

Decompression Stress Required+

No No Yes No

Difficulty Clearing/evidence of MEBT

Not required Generally present

Not required Not required

Coexisting Auditory Signs

Unusual Very common (88%)

Common (38%) Less common

Nystagmus Peripheral Peripheral Central or peripheral

Central or peripheral

Fistula Test Unknown May be positive Unknown Unknown *Except for alternobaric facial palsy +Sufficient time has elapsed on the bottom to allow for inert gas absorption. For sensitive individuals, this may be inside the no-decompression limits. ABV, alternobaric vertigo; CAGE, cerebral arterial gas embolism; DCS, decompression sickness; IEBT, inner-ear barotrauma; MEBT, middle ear barotrauma.

Table 22: Vertigo after Surfacing.58

58


56

NEUROLOGICAL EXAMINATION

Figure 36: Neuro Exam Checklist.

59

59

DIVEMAN, Figure 5A-1a.

57

Figure 37: Neuro Exam Checklist continued.

60

60

DIVEMAN, Figure 5A-1b.

58

Figure 38: Neuro Exam.

61

61

DIVEMAN, Section 5A-3 (pages 58-63).

63

Table 23: Reflexes.

62

62

DIVEMAN, Table 5A-2.

64

Table 24: Strength Tests.

63

63

DIVEMAN, Table 5A-1.

65

Figure 39: Dermatomes and Spinal Cord Segments.

64

64

DIVEMAN, Figure 5A-2a.

66

Figure 40: Dermatomes and Spinal Cord Segments continued.

65

65

DIVEMAN, Figure 5A-2b.

67

ENVIRONMENTAL PLANNING

Figure 41: Environmental Checklist.

66

66


68

Figure 42: Sea States.

67

67


69

Figure 43: Wind/Temperature.

68

68


70

THERMAL CONSIDERATIONS

Table 25: Signs and Symptoms of Hypothermia.

69

Expected Survival Time in Cold Water Water Temperature Exhaustion or Unconsciousness in: Expected Survival Time 70–80° F (21–27° C) 3–12 hours 3 hours – indefinitely 60–70° F (16–21° C) 2–7 hours 2–40 hours 50–60° F (10–16° C) 1–2 hours 1–6 hours 40–50° F (4–10° C) 30–60 minutes 1–3 hours 32.5–40° F (0–4° C) 15–30 minutes 30–90 minutes

<32° F (<0° C) Under 15 minutes Under 15–45 minutes Table 26: Expected Survival Times.

70

69

DIVEMAN, Table 3-1. 70 http://www.ussartf.org/cold_water_survival.htm.

http://www.ussartf.org/cold_water_survival.htm

71

Figure 44: Water Temperature Protection.

71

71


72

Table 27: Heat Stress Signs.

72

72

DIVEMAN, Table 3-2.

73

Figure 45: Thermal Considerations.

73

73

DIVEMAN, Section 6-5 (pages 73-74).

75

ALTITUDE CONSIDERATIONS

Table 28: Repet Groups at Altitude.

74

Figure 46: Treatment at Altitude.

75

74



76

Table 29: Surface Intervals before Ascent to Altitude.

76

76

DIVEMAN, Table 9-6.

77

Table 30: SLED Chart.

77

77

DIVEMAN, Table 9-4.

78

EMERGENCY KITS

CHAMBER EMERGENCY KITS

Table 31: Chamber Primary Emergency Kit.

78

78


79

Table 32: Chamber Secondary Emergency Kit.

79

79


80

DMO MEDICAL BAG

Diving Medicine Physician’s Kit for Remote Locations

EQUIPMENT DRUGS AND FLUIDS Sphygmomanometer NS and LR solution

Stethoscope Injectable Dexamethasone Otoophthalmoscope Sodium Bicarbonate Ampules

Oropharyngeal Airway Local anesthetic solution Endotracheal tubes, scope, blade Aspirin Tablets

Foley Catheter, 18-22 gauge Otic Domeboro Solution Syringes and Needles Cortisporin Otic Solution

Venous Cannula Ophthalmic Antibiotic Solution Tourniquet Afrin Nasal Spray

IV Infusion Sets Benadryl Injection and Capsules Scissors, disposable scalpels Topical Steroid Cream

Bandage Materials Topical Antibiotic Ointment Ace Bandages Hibiclens Surgical Soap Sterile Gloves Antacid Tablets

Ciprofloxacin 500mg Tabs Diazepam Injection Baby Ear Syringe White Vinegar

Table 33: Dive Medicine Kit.80

80

Bove and Davis, Appendix 3, page 579.

82

BASIC DIVING PHYSICS

Gas Laws Boyle’s Law At a constant temperature, the absolute pressure and the

volume of a gas are inversely proportional P1V1=P2V2

Charles’ Law At constant pressure, the absolute temperature and the volume of a gas are directly proportional

𝑉1

𝑇1 =

𝑉2

𝑇2

Gay-Lussac’s Law

At constant volume, the absolute temperature and the pressure of a gas are directly proportional

𝑃1

𝑇1 =

𝑃2

𝑇2

General Gas Law

The general gas law is a combination of Boyle’s law, Charles’ law, and Gay-Lussac’s law, and is used to predict the behavior of a given quantity of gas when pressure, volume, and temperature changes

𝑃1𝑉1

𝑇1 =

𝑃2𝑉2

𝑇2

Dalton’s Law The total pressure exerted by a mixture of gases is equal to the sum of the pressures of the different gases making up the mixture, with each gas acting as if it alone occupied the total volume

Ptotal=p1+p2+p3+…

Henry’s Law The amount of gas that will dissolve in a liquid at a given temperature is almost directly proportional to the partial pressure of that gas

Ideal Gas Law Used to predict the behavior of ideal gases PV=nRT Table 34: Gas Laws.

81

Commonly Used Units of Pressure in the Underwater Environment FSW MSW PSIG PSIA ATA mmHg Gas

Bubble Volume

Gas Bubble Diameter

Sea Level Sea Level 0.0 14.7 1 760 100% 100% 33 10 14.7 29.4 2 1520 50% 79% 66 20 29.4 44.1 3 2280 33% 69% 99 30 44.1 58.8 4 3040 25% 63%

132 40 58.8 73.5 5 3800 20% 58% 165 50 73.5 88.2 6 4560 17% 54% 198 60 88.2 102.9 7 5320 231 70 102.9 117.6 8 6080 264 81 117.6 132.2 9 6840 297 91 132.2 147.0 10 7600

Table 35: Units of Pressure.82

81

Bove and Davis, pages 26-32; DIVEMAN, Chapter 12. 82

Wilderness Medicine, Table 77-2, page 1527.

83

AIR DIVING NO-DECOMPRESSION LIMITS

Table 36: No-D Limits and Repet Group Designators.

83

83

DIVEMAN, Table 9-7.

84

AIR DIVING RESIDUAL NITROGEN TIME TABLE

Table 37: RNT Table.

84

84

DIVEMAN, Table 9-8.

85

REPET DIVES

Figure 47: Repet Dive Worksheet.

85

85


86

Figure 48: Repet Dive Flow Chart.

86

86


87

DIVER AIR QUALITY

Table 38: Dry Atmospheric Air.

87

Table 39: Diver Air Purity Standards.

88

87


DIVEMAN, Table 4-1.

88

Tables 40 and 41: Diver Quality Air Standards.89

89

DIVEMAN, Table 4-2 and 4-3.

89

Tables 42 and 43: Diver Quality Air Standards continued.90

90

DIVEMAN, Table 4-3 and 4-4.

90

Table 44: Diver Quality Air Standards continued.91

91

DIVEMAN, Table 4-5.

91

DIVE PLANNING

Figure 49: Dive Abbreviations.

92

Figure 50: Air Diving Techniques with Limits.

93

92



92

Figure 51: Decompression Selection.

94

94


93

Figure 52: Limits for Air Diving.

95

95


94

Figure 53: Diving Safety.

96

96

DIVEMAN, Figure 6-19 (pages 94-97).

98

Table 45: SCUBA Cylinder Data.

97

97

DIVEMAN, Table 7-1.

99

UNDERWATER SIGNALING

Table 46: Line-Pull Signals.

98

98

DIVEMAN, Table 8-3.

100

Figure 54: SCUBA Hand Signals.

99

99


103

DMO HANDBOOK SOURCES

Alfred A. Bove, Diving Medicine, 4th edition (Philadelphia: Saunders, 2004). “Common Problems with Breathing Gas Under Pressure,” accessed April 2, 2016, http://books.publications.chestnet.org/data/Books/PULM/chapter41-t02.png. DAN Dive and Travel Medical Guide, 5th Edition (Durham, NC: Divers Alert Network, 2015). “Expected Survival Time in Cold Water,” accessed April 2, 2016, http://www.ussartf.org/cold_water_survival.htm. Paul S. Auerbach, Wilderness Medicine 6th Edition, (Philadelphia: Elsevier, 2012). “Seafood Poisoning,” accessed April 2, 2016, http://www.the-travel-doctor.com/seafoodpoisoning.htm. United States Navy Diving Manual, Revision 6 (Washington D.C.: US Government Press, 2008).

http://books.publications.chestnet.org/data/Books/PULM/chapter41-t02.png

http://www.ussartf.org/cold_water_survival.htm

http://www.the-travel-doctor.com/seafoodpoisoning.htm

http://www.the-travel-doctor.com/seafoodpoisoning.htm

diving medical officer handbook · 2017. 9. 15. · basic diving physics 82 air diving...

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