Mixed Gas Diving Supervisor

Question 1

What stations shall be manned by formally (NDSTC) tained mixed gas diver

Answer 1

• Diving Officer
• Master Diver
• Diving supervisor

Question 2

What stations shall be manned by formally trained (NDSTC) surface supplied diver

Answer 2

• Diver
• Standby Diver
• Rack operator
• Console operator
• Timekeeper/Recprder (Logs)

Question 3

What positions can you use a non-diver

Answer 3

• Tender
• Standby Tender
• Winch Operator

Question 4

When is a Diving Medico Officer (UMO) required to be on the side?

Answer 4

• All planned exceptional exposure dives
• Dives planned to exceed normal working limits

Question 5

Is a Master Diver and Dive Medical Technition (DMT) required on dive station for mixed gas operations

Answer 5

Yes

Question 6

What is the Surface Supplied HeO2 Diving Minimum Equipment

Answer 6

• MK 21 MOD 1 or KM-37NS with umbilical
• Thermal protection
• Hot water suit - Wet suit - Dry suit
• Weight belt (If required)
• Dive Knife
• Fins or boots
• EGS w/ submersible tank presure gage
• Surface supplied diving harness

Question 7

What are the normal operational limit for surface supplied mixed gas

Answer 7

300 FSW for 30 Minutes

Question 8

How much sleep do divers need before mixed gas dive

Answer 8

8 hours within the last 24 hours

Question 9

To minimize pulonary O2 tox effects divers should take a ______ break after ______ of diving

Answer 9

Take a 1 day** break after **4 consecutive days of diving

Question 10

Is repeative diving allowed in surface supplied helium oxygen diving

Answer 10

No

(Exception- dive aborted during decent shallower than 100 FSW)

Question 11

Following a “No-Decompression Dive” the diver must wait ______ before making a second dive

Answer 11

12 Hours

Question 12

Following a decompression dive, divers must wait ______ before a second dive

Answer 12

18 Hours

Question 13

Following a no-decompression dive the diver must wait ______ before acent to altitude

Answer 13

12 Hours

Question 14

Following a decompression dive, divers must wait ______ before ascent to altitude

Answer 14

24 Hours

Question 15

Helium has a _____________ wich can cause rapid loss of body and respiratory heat

Answer 15

high thermal conductivity

Question 16

Helium oxygen mixtures must be analyzed with an instument having an accuracy of _______

Answer 16

+/- 0.5 percent

Question 17

Bottom Mixture ranging

Answer 17

90/10 He/O2

to

60/40 He/O2

Question 18

50% He / 50% O2 used for what depth and range of mix

Answer 18

90 FSW to 40 FSW

49-51%

Question 19

100% O2 is used at what depth

Answer 19

Used at in-water SurD

Question 20

What mix is EGS

Answer 20

Same as bottom mixture (unless less than 16% O2, then use range from 15-17% O2)

Question 21

What is the maximum oxygen concentration for a diver never shall exceed an O2 partial pressure of ___________ while on bottom

Answer 21

1.2 ata (Cut off depth)

Question 22

Descending with < 16% O2

Mixed Gas

Answer 22

• Hat bolth divers on air on the surface
• Up/Over to 20 fsw
• Shift to pri BM, vent diver for ::20, leak check
• BT begins when divers leave 20’ or :05 at 20’

Question 23

Abort Procedures < 100’ or > 100’

Mixed Gas

Answer 23

• Ensure divers are in No “D” status
• If BM is > 16% O2, ascend to surfaces 30 fpm
• If BM is < 16% O2, ascend to 20’ shift to air, vent bolth divers, confirm, ascend to surface
• If aborted < 100’ add BT of all dives to BT of new dive, use deepest depth to calculate T/S
• If aborted > 100’ no repet dives

Question 24

Light headed or dizzy on bottom

Mixed Gas

Answer 24

• Have diver stop working, vent rig, verify O2 on Analox
• If bad gas suspected, shift divers/ stby to Sec BM
• If entire gas supply is suspected, shift to EGS, abort

Question 25

Unconsious diver on the bottom Mixed Gas

Answer 25

* Verify MMP and O2% * Check status of other diver * Vent affected diver * if bad gas suspected, shift to Sec BM, vent all divers * Check for breathing, abort dive * Bring diver to first 'D' stop, if breathing continue 'D'

Question 26

Loss of Bottom Mix on the bottom Mixed Gas

Answer 26

* Shift to Sec BM abort dive * If can't shift to Sec BM, shift to EGS, abort dive * at 90 fsw, shift to 50/50, resume decompression * If EGS exhausted before 90', shift to air, shift to 50/50 at 90 fsw, resume decompression

Question 27

Bottom time excess of table Mixed Gas

Answer 27

* Decompress onthe :120 schedule using DD * Shift to 100% O2 at 40 fsw, complete :30 * Sur 'D' up/over to 60'in chamber * TT-6 with max extensions

Question 28

Delay to First sop \> :01 Mixed Gas

Answer 28

* Round delay up to next whole minute, add to BT * Recompute T/S. if no changes, continue deco * If change, preform missed stops at current depth, dont go deeper

Question 29

Delay in leaving or arriving at next stop \> 90' \> :01 Mixed Gas

Answer 29

* Round delay up, add to BT recompute * If no change, continue decompression * If change, pick up new schedule, ignore any missed stops/times

Question 30

Delay in leaving or arriving at next stop \< 90' \> :01 Mixed Gas

Answer 30

* Can be ignored unless between 90' -70' * Delays \> :05 btwn 90'-70' shift to aire, add any time on air to BT, recompute, if change in schedule, pick up new schedule at current depth, ignore any missed stops/times

Question 31

Loss of 50/50

Answer 31

* Shift to air, continue decompression * If fixed, shift back to 50/50, time on air counts * If can't be fixed continue on air to 50 fsw * Shift to 100% O2, NTE :16 at 50 fsw * If exceeds :16 at 50' travel to 40' and add remaining time to 40' stop time, Sur 'D'

Question 32

CNS O2 Toxicity (Nonconvulsive) at 90'-60 stops

Answer 32

* Bring divers up 10' shift to air * Vent affected diver, then unaffected diver * Remain at stop until previouse stop is made up * Continue decompression * At next stop, shift back to 50/50, resume decompression

Question 33

CNS O2 Toxicity (Convulsive) at 90'-60' stops

Answer 33

* Shift to air, vent unaffected diver, than affected * Wait for Tonic/Clonic phase * _If breathing_ decompress to 50', shift to 50/50, Sur 'D' at completion of 40' Stop * _If not breathing_ reposition airway, if still not, launch stby to assist stricken diver to surface, treat for AGE, leave unaffected in water to complete decompression

Question 34

CNS O2 Toxicity (Nonconculsive) at 50'-40' stops

Answer 34

* Up 10', shift to air, vent affected, then inaffected * Douvle missed time if on 50/50, triple if on O2 * Sur 'D' after completion of time * If Sur 'D' is not fesible, continue on Air or O2 * On O2, at 30', take a :10 air break, shift to O2, resume deco * ON Air, at 30', tripple stop time