FAQ's

  • Enter depth, time and gas details as legs into the left column, using the Add Level button at the bottom.
  • Place a check mark next to the legs to be included into plan.
  • Enter deco gases into the deco gas column, using the Add Deco button at the bottom.
  • Place a check mark next to the deco gases to be included into plan.
  • Set a time interval - either by selecting 24 / 48 hrs, or entering actual time.
  • Press the Calc button at top.
  • Follow the run times. The displayed stop times include the time required for transit between stops
  • Do not add any extra stops in the deep sections of the dive. This will add significantly to the decompression obligations. You may extend the shallow stops without side affects.
  • Carry out the ascents at the rates used in the plan. Ascending at a rate faster or slower than specified may require additional decompression.

V-Planner offers the VPM-B and VPM-B/E models for planning dives. The VPM-B is the current model in wide spread use today. VPM-B/E is an extension made for divers undertaking very deep and long dives. It generates plans with additional shallow time that simulate an overlapped bubble model and a Haldane plan, for time times when maximum safety is required. For most divers, the B and B/E plans are the same, because B/E only begins to deviate after large gas loads (90-100 mins deco required).

The VPM in V-Planner is a highly tuned deco tool and you must follow the plans closely. Any large deviations from planned ascent in depth & time during decompression, must be avoided. Significant changes will require additional deco time to compensate. This is most relevant with slowed or delayed ascents in the deepest parts of the ascent.

You may add extra time, if required to the last deco stops without side effects.

Plans with deco mixes will generate slightly faster run times for the mid level stops - even before any gas change has occurred. VPM calculates decos in an iterative process, and adjusts for additional off gassing capability later in the deco from the high O2 mixes to come.

If you are forced to adopt a new plan in water from lost / broken deco gas - wait out the additional time between the two plans, at the current level, and then commence timings per the new plan. (see also question 1 in top ten)

A faster deco from deep dives is usually possible when the first deco gas switch is at, or just above, the same level as the first deco stop. High helium deco mixes after trimix dives, usually do not accelerate deco.

All switch depths onto deco gases / mixes, are controlled by the ppO2 settings in configuration. The program will select a gas from the checked items in the deco gas list, based on the max ppO2 settings, for each of the required stops.

Switches in mixes during the dive are controlled by inserting legs into the plan, with a time of zero(-). e.g.

Switch in descent from travel to bottom mix.

25, - , 32 travel gas 32% to 25m.
95, 30, 12/60 30 mins at 95m, on 12/60 mix

Multi level descent with switch

22, 5, 32 5 mins at 22m, 32%
22, - , 18/30 swap to bottom mix when leaving 22m
65, 20, 18/30 20 mins at 65m on mix

Switch in ascent, on a multi level plan.

40, 30, 21 30 mins at 40m, air
21, - , 50 swap to 50% in ascent at 21m
10, 20, 50 20 mins at 10m

The program reads down the list of legs, and creates plans based on the order each leg is encountered. To rearrange the order of legs - drag the selected leg up / down the list (hold down left mouse button), or right click and select Sort List.

The program reads down the list, and creates plans based on the order each leg is encountered. Multi level plans (or cave profiles) are entered by specifying each level (and gas change) in sequence. e.g.

Multi level descent with switch

22, 5, 32 5 mins at 22m, 32%
22, - , 18/30 swap to bottom mix when leaving 22m
65, 20, 18/30 20 mins at 65m on mix

Multi level ascent.

40, 30, 21 30 mins at 40m, air
10, 20, 21 20 mins at 10m, air

Multi level ascent, with gas switches.

55, 25, 18/25 25 mins at 55m, 18/25 mix
21, - , 50 swap to 50% at 21m
10, 20, 50 20 mins at 10m, 50%

Multi level saw tooth dive.

60, 25, 18/30 25 mins at 60m, 18/30 mix
10, 20, 21 20 mins at 10m, swap to air
30, 15, 21 back down to 30m on air
15, 25, 21 up to 15m for 25 mins on air

In all cases above, any gas in the deco column is not utilized until the last dive plan leg has been processed. If a switch to another gas is required in mid water, then insert a leg with a time of zero. See travel gas.

On multi level ascent plans with sufficient change between levels, V-Planner will insert decompression stops mid water prior to reaching the next level.

The program reads down the list of legs, and creates plans based on the order each leg is encountered. To rearrange the order of legs - drag the selected leg up / down the list (hold down left mouse button), or right click and select Sort List.

Feedback from divers has suggested the following settings should be applied. Nominal is for navy divers and the super fit. Plus 2 or 3 is the normal setting for most divers. Set a plus 3 or 4 with strenuous, cold, a series of multi day dives, extra safety, or a prior history of DCS or symptoms.

Inside the program, the conservatism setting increases the Critical Radii of N2/He in the VPM algorithms. From these base values, by this increase: 1 = 5%, 2 = 12%, 3 = 22%, 4 = 35%, 5 = 50%. The Critical Volume setting is on by default.

This adjustment chooses the threshold of micro-nuclei radius size, that becomes the limiting dimension through the ascent and decompression. This adjustment operates at the core of the VPM algorithm. This setting operates in reverse: a larger radii is a more conservative plan.

You may notice on some dives in VPM, setting the conservatism higher has little apparent effect. This will happen because at some point, decompression is complete no matter how much extra conservatism is added.

Do not fake conservatism in VPM e.g. using Nominal and inflating the depth or time. Doing so will cause the repetitive factor time penalty to be reduced, and subsequent dives plans will have insufficient deco time applied.