Air Decompression Variations in Ascent

Question 1

Travel Rate Exceeded

Answer 1

1. Stop the ascent, allow the watches to catch up.

2. Continue Ascent.

Question 2

Early Arrival at the First Decompression Stop.

Answer 2

1. Begin the stop time when the required travel time has been completed.
2. If the first stop is an oxygen stop: Shift to oxygen upon arrival at the stop, Begin stop time when the divers are confirmed on oxygen and the required travel time has been completed.

Question 3

Delay in Arriving at the First Decompression Stop:

Delay up to 1 minute

Answer 3

1. Disregard.

Question 4

Delay in Arriving at the First Decompression Stop:

Delay greater than 1 minute, deeper than 50 feet

Answer 4

1. Round the delay up to the next whole minute and add it to the bottom time.
2. Recompute the decompression schedule.
3. If a change in schedule is required and the new schedule requires decompression stops deeper than the divers current depth. perform any missed stops at the current depth. DO NOT GO DEEPER.

Question 5

Delay in Arriving at the First Decompression Stop:

Delay greater than 1 minute, shallower than 50 feet

Answer 5

1. Round the delay up to the next whole minute and add it to the divers first decompression stop.

Question 6

Delay in Leaving a Stop or Between Decompression Stops:

Delay less than 1 minute leaving an air stop

Answer 6

1. Disregard.

Question 7

Delay in Leaving a Stop or Between Decompression Stops:

Delay less than 1 minute between air stops

Answer 7

1. Disregard.

Question 8

Delay in Leaving a Stop or Between Decompression Stops:

Delay greater than 1 minute leaving an air stop or between air stops deeper than 50 feet

Answer 8

1. Add the delay to the bottom time and recalculate schedule.
2. If a new schedule is required, pick up the schedule at the current stop or next stop if between stops.
3. ignore any missed stops or time deeper than the depth the delay occurred.

Question 9

Delay in Leaving a Stop or Between Decompression Stops:

Delay greater than 1 minute leaving an air stop or between air stops shallower than 50 feet

Answer 9

1. Disregard.

Question 10

Delay in Leaving a Stop or Between Decompression Stops:

Delay leaving oxygen stop at 30 feet or delay between oxygen stops 30 and 20.

Answer 10

1. Subtract the delay from the 20 foot oxygen time.
2. if the delay causes the total time on oxygen deeper than 20 feet to exceed 30 minutes. shift the diver to air at the 30 minute mark. When the problem has been resolved, shift back to Oxygen and resume decompression.
3. ignore any time spent on air.

Question 11

Delay in Leaving a Stop or Between Decompression Stops:

Delay in leaving the 20 foot oxygen stop

Answer 11

1. Disregard.

However do not leave the divers on oxygen for longer than 30 minutes. Shift to air and remain on air until travel to the surface is possible.

Question 12

Delay in Leaving a Stop or Between Decompression Stops:

Delay in Travel from 40 feet to the Surface for Surface Decompression

Answer 12

1. Disregard unless the surface interval exceeds 5 minutes.

Follow SurD procedure.