Multilevel Dives — eRDPml Study Notes

eRDPml — Topics

Dive Planning Mode Surface Interval Mode Multilevel Dives Practice Questions
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The Staircase Diagram

Multilevel dive questions require a different diagram. Instead of the standard two-dive layout, draw a staircase — three steps descending left to right, then ascending — to represent a diver going to the deepest level first, then moving to progressively shallower levels. Label each step with depth and time slots, and add a pressure group box at the top of each ascent between levels. These intermediate pressure group boxes are what you record as the device works through each level in turn.

The Staircase Diagram — What Goes Where For each level: depth (top of the step) and time (bottom of the step).
Between each level: a pressure group box showing the PG as you ascend from one level to the next.
Final box: ending pressure group after the shallowest level.

Fill in all depths and times from the question before picking up the device.

Using the Multilevel Function

Multilevel dives are not a separate operating mode — they are accessed through Dive Planning Mode. The distinction is made at the first yes/no prompt after selecting the mode.

Multilevel Dives eRDPml tutorial — Will Welbourn, Go Pro Caribbean
Multilevel Dive Sequence — Step by Step 1. Dive Planning Mode → Enter
2. Multi-level? → Yes → Enter
3. First dive? → Yes (if no previous dives mentioned) → Enter
4. Enter depth of level 1 (the deepest level) → device shows NDL for that depth; press Enter
5. Enter time at level 1 → device shows the pressure group as you ascend to level 2; record it on your staircase diagram
6. Enter depth of level 2 → device shows ANDL for level 2; press Enter
7. Enter time at level 2 → device shows the pressure group as you ascend to level 3; record it
8. Enter depth of level 3 (the shallowest level) → device shows the multilevel limit; press Enter
9. Enter time at level 3 → safety stop warning if required → Enter
10. Device shows ending pressure group
Always enter levels from deepest to shallowest The device expects levels in descending depth order — deepest first. If a question lists levels in a different order, rearrange them on your staircase diagram before starting. The device also constrains the allowable depth at each subsequent level based on the nitrogen accumulated so far, so the order matters.
Worked Example — Multilevel Dive, Ending Pressure Group A multilevel dive: level 1 is 120 ft for 12 min, level 2 is 80 ft for 8 min, level 3 is 40 ft for 50 min. What is the ending pressure group?
  1. Draw the staircase diagram. Enter depths and times from the question: 120 ft / 12 min, 80 ft / 8 min, 40 ft / 50 min.
  2. Dive Planning Mode → Multi-level? Yes → First dive? Yes.
  3. Enter depth level 1: 120 ft. Device shows NDL for 120 ft → press Enter.
  4. Enter time: 12 min. Device shows pressure group ascending to level 2 → record on diagram.
  5. Enter depth level 2: 80 ft. Device shows ANDL → press Enter.
  6. Enter time: 8 min. Device shows pressure group ascending to level 3 → record on diagram.
  7. Enter depth level 3: 40 ft. Device shows multilevel limit → press Enter.
  8. Enter time: 50 min. Safety stop warning → Enter.
Ending pressure group: X.
The Multilevel Limit At the shallowest level, the device displays a multilevel limit rather than a simple ANDL. This is the maximum time you can spend at that level given the nitrogen absorbed at all previous levels. It is usually different from — and often shorter than — the ANDL you would get if you started the dive fresh at that depth. If the question asks you to spend the maximum time at each level, use this multilevel limit figure for the shallowest level.