Us Navy Dive Manual Chapter 18 Rev 6 Change A

Front 1

What is the normal working limit when diving the MK 16 MOD 1?
-N2O2
-HEO2

Back 1

-150 fsw N2O2 (air)
-300 fsw HeO2 (88/12)

Front 2

What is considered exceptional exposure when diving N2O2?

Back 2

Due to increased breathing resistance and concerns about carbon dioxide retention and CNS O2 toxicity, planned N2O2 dives deeper than 150 fsw are considered exceptional exposure dives and require prior CNO approval.

Front 3

When using N2O2 as a diluent, what is the MK 16 Mod 1 Operational Characteristics?

Back 3

Normal working limit: 150 fsw, Maximum: 190 fsw
Permissible 1.3 ata N2O2 dive profiles
-multiple repet dives from 0-150 fsw provided all the dives are No "D" dives
-1 deco dive from 0-150 fsw plus up to 3 additional No "D" dives from 0-150 fsw. The 3 No "D" dives may precede, follow, or bracket the decompression dive.
-2 deco dives (initial deco dive plus one repet deco dive) from 0-150 fsw. Additionally No "D" dives are not allowed before of after the deco dives.
-repet dives from 151-190 fsw under the rules above providing CNO grants a waiver for exceptional exposure diving.
Switching diluents between dives is NOT authorized. A repetitive dive on air can be done following a dive on N2O2

Front 4

What are the operational characteristics of the rig when diving HeO2 as a diluent?

Back 4

Normal: 300 fsw, Max: 300 fsw
Premissible 1.3 ata HeO2 dive profile
- multiple repet dive from 0-200 fsw provided all the dives are No "D" dives.
- 1 deco dive from 0-200 fsw plus up to 3 additional No "D" dives from 0-200 fsw. The 3 No "D" dives may precede, follow, or bracket the decompression dive.
- 2 deco dives (initial deco dive plus one repet deco dive) from 0-200 fsw. Additionally No "D" dives are not allowed before of after the deco dives.
- 1 No "D" dive or 1 decompression dive from 201-300 fsw. Repet diving is not allowed deeper than 200 fsw.

Front 5

Is switching diluents between dives authorized?

Back 5

No, there are no procedure for performing a repetive dive on N2O2 following a dive on HeO2 or vice versa.

Front 6

Can repetive dives on air be performed following a MK 16 MOD 1 dive on nitrogen?

Back 6

Yes

Front 7

When shall a full face mask be used?

Back 7

When deploying a single untended diver, single marked diver, paired marked diver, and when using an approved BC.

Front 8

What are the three levels of chamber requirements?
Can a non-Navy chamber be used to meet the requirement?

Back 8

Level I- Within 5 minutes
Level II- Within 1 hour (level I and II non-Navy chamber requires CNO approval in writing)
Level III- Within 6 hours ( non-Navy chamber requires CO approval in writing)

Front 9

What is required prior to any planned dive which exceeds the normal working limits, N2O2 or HEO2?

Back 9

CO approval

Front 10

What should tending lines be manufactured from and how shall the lines be marked?

Back 10

-Lines should be manufactured from any light line that is bouyant. (1/4 inch polypropylene is quite suitable)
-Lines should be marked starting at the clump
-50 ft. red bands
-10 ft. yellow or black bands
Red Red Black Black would be 120'

Front 11

What are the 6 general MK 16 MOD 1 diving equipment requirements?

Back 11

1. motorized safety boat
2. Radio (comms w/ parent unit, chamber, comms. between safety boats.)
3. High intensity wide beam light( night ops)
4. Dive flags and & or special ops. light as required.
5. sufficient (2 qtrs.) fresh water in case of chemical injury
6. E.B.S. for planned decommpression dives.

Front 12

When can open circuit scuba be used for stby diver during MK 16 diving?

Back 12

-When appropriate during training & non-influence diving operations.
SCUBA work limits
1. Normal 130 fsw
2. Max 190 fsw with CO or OIC permission
3. 100 fsw using SCUBA cylinders with less than 100 scf
4. STBY diver with atleast 100 scf cylinder capacity for dives deeper than 60 fsw.
5. Within no-D limits
6. Current 1 knot max. Current greater than 1 knot, requires ORM analysis as a minimum. The divers must be tended or witness float.

Front 13

What are the minimum manning requirements for a MK 16 dive team?

Back 13

-4 for 1 diver
-5 for 2 divers
1-Dive supervisors (May act as time keeper/recorder, stby tender.
1 or 2-Divers
1-Stby diver (at dive sups discretion, the stby diver shall be fully dressed w/ the exception of scuba or MK 16 MOD 1, mask & fins. These items shall be ready to don.)
1-Diver tender (1 tender per diver when divers are surface tended. If using a buddy line, 1 tender is required for each buddy pair.
*EBS operator is required for MK 16 MOD 1 decompression dives.

Front 14

What must a MK 16 MOD 1 diver do prior to a deco. dive if he has not conducted one within the previous 6 months?

Back 14

He must complete open water deco. training dives.

Front 15

What must a MK 16 MOD 1 diver do if he has not made a MK 16 dive within the previous 6 months?

Back 15

1. Refamiliarize himself with the MK 16 MOD 1 EPs & OPs
2. Complete MK 16 MOD 1 training dive prior to making a operational dive.

Front 16

How may MK 16 MOD 1 diver qualifications be obtained?

Back 16

1. By completion of the MK 16 MOD 1 basic course (A-431-0075).
2. Qualifications remain in effect as long as dive qualifications are maintained in accordance with military personnel manual article 1220-100.

Front 17

What is considered exceptional exposure dives and why?

Back 17

Due to an increased breathing resistance, and concerns about CO2 retention & CNS O2 toxicity, planned N2O2 dives deeper than 150 fsw are considered exceptional exposure dives and require prior CNO approval.

Front 18

What are buddy lines and distance lines?

Back 18

Buddy lines - 6 - 10 ft. (3 meters) in lenght
Distance line - Any buddy line over 10 ft. in lenght but shall not exceed 81 ft. (25 meters). Distance lines shall be securely attached to both divers.

Front 19

When is a safety boat required and when is it recomended?

Back 19

Required - A minimum of 1 motorized safety boat must be present for all open-water dives.
Recommened - Tended pier dives or diving from shore.

Front 20

How is the diluent gas used in the MK 16 MOD 1 rig?

Back 20

Diluent gas is used to maintain the required gas volume in the breathing loop and is not depleted by metabolic consumption.

Front 21

What standard safety procedures shall be observed during EOD diving operations?

Back 21

1. An EOD diving officer is required to be in tactical control of all EOD diving operations tha involve render safe procedures (RSP). Tactical control is defined as either on-station or in continuous, full time tactical voice communications with the dive team conducting the RSP.
2. When diving on unknown or influence ordnance, the stby diver's equipment whall be the same type as the diver performing the actual procedure.

Front 22

When may an EOD diving officer authorize the employment of a single, untended diver?

Back 22

When it is deemed that the ordnance hazard is greater than the hazard is greater than the hazard presented by diving alone. All single, untended divers shall use a full fask mask(FFM).
Considerations
-Experence of the diver
-Confidence of the team
-Type and condition of ordnance suspected
-Environmental conditions
-Degree of operational urgency required

Front 23

What are the MK 16 MOD 1 "diver to tender" line pull signals?

Back 23

1 pull: Arrived at lazy shot (given on lazy shot).
7 pull: I have started, found, or completed work.
2-3 pulls: I have decompression symptoms.
3-2 pulls: Breathing from EBS (EBS UBA is functioning properly).
4-2 pulls: Rig malfunction
2-1 pulls: Unshackle from the lazy shot
5 pulls: I have exceeded the planned depth of the dive. (This is followed by 1 pull for every 5 fsw of depth the planned depth was exceeded).

Front 24

What is the maximum descent rate?

Back 24

60 feet per minute.

Front 25

What may happen to the primary display on descent depending on the rate of descent?

Back 25

The primary display may illuminate flashing green. It may take 2 - 5 mins to consume the additional O2 added by the dilluent during descent.

Front 26

During the descent phase of the dive. Dive sups and divers should be aware that PPO2 of 1.6 ata or higher may be temporarily experienced during descent on N2O2 dives deeper than _____ fsw (21% O2 diluent) and on HeO2 dives deeper than ____ fsw (12% O2 diluent) which causes an increased risk of oxygen toxicity.

Back 26

-120' N2O2 21% O2 diluent
-200' HEO2 12% O2 diluent

Front 27

At what depth should the primary display indicate a transition from 0.75 ata to 1.3 ata?

Back 27

At 33 fsw

Front 28

While on descent, at what depth shall the dive be terminated if there is no transition?

Back 28

The diver should verify this transition with the secondary display. If there is no transition with continued descent past 40 fsw, the dive should be terminated.

Front 29

What general guidelines should divers adhere to as the dive is conducted?

Back 29

-Monitor primary and secondary display
-Don't add O2 on descent, except as part of an emergency procedure or at anytime while on the bottom due to the increased risk of CNS O2 toxicity
-Wear adequate thermal protection
-Know and use the proper amount of weights for the thermal protection worn and the equipment carried
-Check each others equipment for leaks
-Do not exceed the UBA canister duration and depth limitaions for the dive
-Minimize gas loss from the UBA (avoid mask leaks and frequent depth changes)
-maintain frequent visual or touch checks with buddy
-Be alert for SX suggestive of a medical disorder
-Use tides and currents to maximum advantage

Front 30

How often should you check the primary and secondary display and your high pressure indicators while you are at depth?

Back 30

Primary display-frequently to ensure the O2 level remains at the set point.
Secondary Display-Every 2-3 minutes to ensure that all sensors are consistent with the primary display and the battery voltages are properly indicating
HP indicators-frequently to ensure the gas supply is adequate to complete the dive.

Front 31

What is the maximum ascent rate for the MK 16 MOD 1?

Back 31

30 FPM, ensure it is not exceeded

Front 32

What may the primary display show while on ascent when water pressure decreases faster than the O2 can be added via the O2 addition valve?

Back 32

The primary display may show an alternate red/green then flashing red for low ppO2.

Front 33

Is planned surface decompression authorized for MK 16 MOD 1 operations?
In an emergency, where a level I chamber is available (within :05) can you recompress an asymptomatic ommited "D" diver in the chamber to fullfil decompression requirements?

Back 33

Planned surface decompression is not authorized but if an asymptomatic diver ommits a 20' decompression shop and has a SI of 1-5 minutes you may recompress him in the chamber to perfomr "D" stops. Once at 20' in the chamber place the diver on 100% O2 and multiply the stop time by 1.5. SSurface interval cannot exceed :05 to use this procedure, if you exceed :05 for asymptomatic ommited "D" use a TT-6.

Front 34

During descent, at what depth does the MK 16 MOD 1 switch from a 0.75 ata mode to the 1.3 ata mode?

Back 34

33'

Front 35

What is the RNT and RHT exception rules and how does it apply to repetitive MK 16 MOD 1 diving?

Back 35

Determine the table and schedule for the repetitive dive by adding the bottom times and taking the deepest depth of all the dives in the series, including the planned repetitive dive. If the resultant table and schedule require less deco than the table and schedule obtained using the repetitive dive worksheet, it may ne used instead of the worksheet table and schedule

Front 36

When some dives are shallower than 35' and others are deeper, how do you convert 0.75 ata dives to 1.3 ata dives to use the RNT/RHT exception rule?

Back 36

The equivalent depth on 1.3 can be obtained by adding 20 fsw to the depth of the dive on 0.75 ata.

Front 37

-What is the depth limit of the MK 4 life preserver?
-When wearing an approved dry suit while diving the MK-16 is a BC or life preserver required?

Back 37

-200'
-No

Front 38

What are the recompression chamber requirements for MCM Operations?

Back 38

Level I- Not required
Level II- All D dives with stops deeper than 20' or total "D" time exceeding :30. All exceptional exposure dives (requires CNO approval)
Level III- All no "D" dives. All "D" dives with a single stop at 20' and total "D" time less than :30.

Front 39

What are the recompression requirements for exercises, training, qualification, and other diving?

Back 39

Level I- All dives deeper than 200'. All dives with "D" stops deeper than 20' or total "D" time exceeding :30.
All exceptional exposure dives(requires CNO approval)
Level II- All "D" dives 200' and shallower with a single stop at 20' and total "D" time of :30 or less.
Level III- All no "D" dives shallower than 200'.

Front 40

All exercise, training, qualification, and other dives deeper than 150' requires who's permission?

Back 40

Commanding Officers

Front 41

Are the repet group designators interchangeable between N2O2 and HE02 when diving the MK-16 MOD 1?

Back 41

No, there are no procedures to switch between the two. You can only repet using the same diluent.

Front 42

At what depth does the MK-16 MOD 1 swith from
-0.75 ata to 1.3 ata PPO2?
-1.3 ata PPO2 to .75 ata PPO2?
And what are the allowable ranges

Back 42

-33' +/- 2' (1.15, ata -1.45 ata)
- Upon ascent above 13' (0.60 ata- 0.90 ata)

Front 43

At what depth is the partial pressure of inert gas (nitrogen or helium) in MK 16 MOD 1 lower than the partial pressure of nitrogen in the air? What does this mean?

Back 43

15' and less. Dives to this depth will cause your body to lose rather gain inert gas during the dive. Any dives to this depth can be considered the equivelant of remaining on surface, in the event of a repet following the dive to 15' or shallower consider it part of your surface interval.

Front 44

How do you perform a N2O2 MK 16 MOD 1 dive following an air dive?
Can the RNT exception rule be used?

Back 44

-Obtain repet group designator from the air table and carry it over to the MK 16 MOD 1 tables to obtain RNT.
-The RNT exception rule does apply to Air-MK 16 MOD 1. If all the dives in the MK-16 series are to 35' or shallower convert the air dive depths to equivelent depth on 0.75 ata and if any of the repet dives are to greater than 35' convert the air dives to the equivalent depth on 1.3 ata.

Front 45

True or False? A diver that has been breathing a mixture with PPO2 lower than 1.15 ata for any length of time may have a greater risk of developing decompression sickness.

Back 45

True, but need not be treated unless symptoms of decompression sickness occur

Front 46

State EBS deployment procedures, placement in the water column, water current and EBS ascent procedures

Back 46

-Regardless of the first deco stop the EBS must be lowered to 40' to allow for transition, it can then be raised or lowered to 10' below the first deco stop. It is recommended to lower the EBS to 50' if the first deco stop is shallower than 40' to allow tracking delays in ascent to 50'
-In currents ensure that a tag line to counter the current is used from the opposite end of the boat
-As divers prepare to leave bottom use a weighted carabineer or other attachment device to connect the tending line to the EBS line. Drop the weight to the EBS to allow the diver to be tended directly to the EBS

Front 47

What are the precautions when multi-day diving operations are being performed?

Back 47

Repetitive exposure to an oxygen PPO2 of 1.3 ata over a multi-day period may result in the gradual onset of pulmonary O2 toxicity and visual O2 toxicity

Front 48

What are the symptoms of pulmonary O2 toxicity and visual O2 toxicity?
If a diver develops any symptoms in relation to O2 tox what must be done?

Back 48

-Pulmonary O2 tox: burning, substernal pain on inspiration, chest tightness, cough, and/or shortness of breath
-Visual O2 tox: temporary change in visual activity to include distant objects being out of focus
-Stop diving until diver is symptom free for 24 hours

Front 49

What are the mutli-day diving limits
___ hours a day
___ hours a week
Can provided limits be exceeded?

Back 49

-4 hours a day
-16 hours a week
These limits can be exceeded with permission of CO and consultation with NEDU

Front 50

What are the required wait times for flying after diving the MK 16 MOD 1?
-N2O2
-HEO2

Back 50

-N2O2: Use the highest repet group designator obtained in the previous 24 hours and apply it to table 9-6 (ascent to altitude after diving) in the air decompression chapter.
HEO2: For no "D" dives with less than 2 hours of BT wait 12 hours. For all "D" dives and no "D" dives with a BT greater than 2 hours wait 24 hours

Front 51

To what altitude can the MK 16 MOD 1 decompression procedures be used?

Back 51

Up to 1000' of altitude, for dives above 1000' contact NAVSEA for guidance

Front 52

What factors increase the likelihood of CNS O2 toxicity?

Back 52

-Increased PPO2
-Increased time of exposure
-Prolonged immersion
-Stress from physical exercise
-CO2 build up
-Cold stress
Systemic disease that increase O2 consumption such as thyroid or adrenal disorders. Divers with these disorders shall be excluded from mixed gas diving

Front 53

A rapid descent may not allow the PPO2 in the circuit to be consumed fast enough. When a diver is in less than ___ fsw little risk of O2 tox exists, but if the diver is deeper than ____ fsw and a PPO2 of ____ ata or higher persists for a period of ___ consecutive minutes this should be considered a malfunction and the appropriate EP should be followed.

Back 53

20 fsw
20 fsw
1.45 ata
15 minutes

Front 54

CNS O2 toxicity: Treatment of non convulsive symptoms?

Back 54

1. Ascend to lower PPO2
2. Add diluent to breathing loop
3. Secure oxygen cylinder if addition is uncontrolled
4. Terminate the dive, notify supervisor

Front 55

CNS O2 toxicity: Treatment of underwater convulsion?

Back 55

1. Assume postion behind diver, release the victims weights only if progress to the surface is significantly impeded.
2. Leave mouthpiece in, do not attempt to replace it if it's not. Switch the mouthpiece to SURFACE position to prevent rig flood out
3. Grasp the victim around his chest using the best method to gain positive control
4. Ventilate the UBA with diluent to lower PPO2 and maintain depth until convulsion subsides
5. Make a controlled ascent to first deco stop, apply slight pressure to chest to assist in exhalation
--If diver regains control, continue normal "D"
--If diver remains incapacitated continue to the surface maintaining ascent rate and airway. Treat for omitted "D" appropriately
-- Frequently monitor the primary, secondary and bottle gauges for rig status and breathing gas
6. Use the victims BC for additional buoyancy if needed
7. Upon surfacing inflate the victims BC
8. Remove the victim's mouthpiece and ensure the mouthpiece is in the surface position to reduce the chance of rig flood out and additional weight
9. Signal for emergency pick up
10.Commence mouth to mouth if needed
11. If an upward excursion occurred during the actual convulsion transport to chamber for evaluation of diving related illness.

Front 56

What is the off-effect?

Back 56

A hazard associated with CNS O2 toxicity, may occur several minutes after the diver comes off gas or experiences a reduction of PPO2. The off-effect is manifested by the onset or worsening of CNS O2 tox

Front 57

What are some causes of hypoxia when diving the MK 16 MOD 1?

Back 57

- Failure of the O2 addition valve
- Failure of the primary electronics assembly
- Rapid ascent (daltons law)
- Decrease in oxygen supply
- malfunctioning sensors

Front 58

What are the symptoms of hypoxia?

Back 58

- Confusion
- Loss of coordination
- Dizziness
- Convulsion
- Unconciousness

Front 59

How do you treat hypoxia?
How do you treat hypoxia when divers require decompression?

Back 59

-Raise PPO2, if unconsciousness occurs the buddy should add O2 to the rig while monitoring the secondary display. Bring the diver to the surface at a moderate rate, remove the mouthpiece and have him breathe air. If it is clear that hypoxia was the cause and the diver recovers with normal neurological function do not treat for AGE
-For deco: If consciousness is regained, continue "D"
If consciousness is not regained ascend at moderate rate maintaining the airway. Once on surface administer 100% O2 and treat for symptomatic omitted "D". Launch standby diver to assist. Unaffected diver shall perform required "D" as planned.

Front 60

What are some causes of hypercapnia when diving the MK 16 MOD 1?

Back 60

- Failure of CO2 absorbent material
-Channeling
-Flooding
-Saturation of the absorbent material
-Skip breathing or controlled ventilation can also result in insufficient removal of CO2 from the divers body

Front 61

What are the symptoms of hypercapnia?

Back 61

- Increased Sweating
- Increased rate and depth of breathing (labored)
- Confusion
- Convulsions
- Headache
- Inability to concentrate
- Loss of consciousness
- Dizziness

Front 62

How do you treat hypercapnia?

Back 62

- Stop work take several deep breathes
- Increase ventilation if skip breathing is cause
- Ascend to reduce the partial pressure of CO2
- If symptoms do not rapidly abate, abort dive
- During ascent maintain a vertical position and activate the diluent bypass valve to add fresh gas. If the symptoms are a result of a flood out this will decrease the risk of chemical injury to the diver.
-Handle an unconscious diver the same as you would with managing an underwater convulsion

Front 63

What are some ways to prevent hypercapnia?

Back 63

- Use only approved carbon dioxide absorbent
- Follow the prescribed canister filling procedure
- Dip test the UBA before the dive, check for leaks
- Ensure one way valves are installed correctly
- Swim at comfortable pace and do not skip breathe

Front 64

What does the term chemical injury refer to and what are the causes?

Back 64

It refers to the introduction of a caustic solution from the carbon dioxide scrubber of the UBA into the upper airway of a diver caused by water coming into contact with the CO2 absorbant as a result of improper predives or an incorrect position of the mouthpiece assembly during a leak check or in water checks.

Front 65

What are the symptoms of a chemical injury (caustic cocktail)?

Back 65

Before actually inhaling the caustic solution the diver may experience labored breathing or a headache which are caused by the CO2 buildup.
- Choking/gagging
- Foul taste
- Burning of mouth and throat

Front 66

Describe management of a chemical injury.

Back 66

-Immediatly assume an upright position
-Depress the manual diluent bypass valve continuously
-No "D" dive: Abort dive ascend to surface exhaling through the nose to prevent overpressurization
-"D" dive: Shift to EBS or alternate breathing supply and complete "D", if that is not possible surface and treat for ommited "D".
-Rinse mouth with fresh water several times but do not swallow. Do not rinse with weak acid solutions and do not induce vomitting.
-Obsreve for signs of AGE and treat as required and have px evaluated by a physian or corpsman. Respiratory distress may require hospitalization.

Front 67

What can be done to prevent chemical injury?

Back 67

-Careful predive dip test
-Pay special attention to mouthpiece rotary valve upon water entry and exit
-Dive buddies perform careful leak checks

Front 68

Describe the management of asymptomatic diver?
*Chamber available within 60 minutes
1. No stops required
2. 20' stop required (<:01 SI, 1-5min SI, >:05 SI)
Note 1
3. Deeper than 20' stop required (0-5 min SI, > :05 SI, >:30 "D" missed)
Note 1

Back 68

1. Observe on surface for one hour
2. <1 min SI. Return to 20' and add :01 to stop time
1-5 min SI. Return to 20' and multiply stop time by 1.5
>5 min SI. TT-6
3. 0-5 min SI. TT-5
>5 min SI. TT-6
>30 min "D" missed. TT-6
Note 1: If the diver is returned to an omitted "D" stop shallower then 33' then he must manually drive the rig.

Front 69

Describe the management of asymptomatic diver?
*Chamber NOT available within 60 minutes
1. No stops required
2. 20' stop required
Note 1
3. Deeper than 20' stop required
Note 1

Back 69

1. Observe on surface for one hour
2. <1 min SI. Return to 20' and add :01 to stop time
1-5 min SI. Return to 20' and multiply stop time by 1.5
>5 min SI. Return to 20' and multiply stop time by 1.5
3. 0-5 min SI, >5 min SI, >30 min "D" missed. For all listed descend to depth of deepest stop and multiply all stop times 40' and shallower by 1.5.
Note 1: If the diver is returned to an omitted "D" stop shallower then 33' then he must manually drive the rig.

Front 70

How do you handle in water decompression sickness when the diver feels he can remain in the water?

Back 70

-Dipatch the standby diver to assist
-Have the diver descend to depth of relief in 10' incriments, but no monre than 2 incriments (20')
-Multiply all stop times by 1.5, if deeper than deepest planned stop use deepest planned stop time for the one or two stops deeper than the original stop.
-Ascend on new profile, extend as needed to control sx
-Upon surfacing transport to nearest appropriate chamber for treatment, use TT-5 if asymptomatic.

Front 71

How do you handle in water decompression sickness when the diver cannot safely remain in the water?

Back 71

-Surface the diver at a moderate rate NTE 30 fpm
-If alevel I chamber is available recompress immediatly and treat appropriately.
-If the stricken must be transported to the nearest chamber have him breather 100% O2 and regardless of improvements treat for original sx.