Every control on the planner’s Plan step, in the order the tabbed sections appear. Each setting belongs to the plan that uses it rather than to your account, and “where the planner starts” is what a new plan opens with.
Depth Profile
One card per level, in the order you dive them. Descent to the first level and ascent between levels are generated for you.
| Setting | What it does | Where the planner starts |
|---|---|---|
| Depth (m) | The depth of this level. The deepest one sets the dive’s max depth. | 20 m on a new level |
| Bottom time (min) | Time held at that depth. It excludes the descent to the level and the ascent away from it. | 15 min on a new level |
| Level label | Your own name for the level. Optional, and it changes nothing about the schedule. | Empty |
A level with no bottom time still appears in the gas ledger but adds nothing to the profile. See Depth levels.
Gas Mixes
Each gas is built through a short wizard; the settings in it are below.
The cylinder
| Setting | What it does | Where the planner starts |
|---|---|---|
| Cylinder Configuration | Single Tank, Backmount Double, Sidemount, Stage Tank or Drop Tank on open circuit; Onboard Diluent, Stage Tank or Drop Tank on a rebreather. It sets how many cylinders of this gas you carry and which roles the gas may take. | Single Tank |
| Tank Size (L) | The cylinder’s internal volume. Without it, gas volume is reported but no pressure. | Empty |
| Quantity | How many cylinders of this configuration. A double or a sidemount pair counts as two. | 1 |
| Working Pressure (bar) | What the cylinder is filled to. Needed, with the tank size, for any pressure figure or turn pressure. | Empty |
The mix
| Setting | What it does | Where the planner starts |
|---|---|---|
| O₂ % | Oxygen fraction. It drives ppO₂, MOD, CNS and OTU. | 21 % |
| He % | Helium fraction. Nitrogen is whatever is left. | 0 % |
| Target Depth (m) and Max ppO₂ | The calculator mode: give it the depth you want to breathe the gas at and the ppO₂ you will accept, and it works out the mix. See Best mix. | — |
| Mix Name | Your own name for it. Left empty, the gas names itself: Air, 50%, 21/35. |
The automatic name |
| Graph Color | The colour this gas is drawn in on the profile and the schedule. | Assigned from the palette |
Its role and limits
| Setting | What it does | Where the planner starts |
|---|---|---|
| Gas Role | Back Gas, Travel Gas, Deco Gas on open circuit; Onboard Diluent, Offboard Diluent, Bailout or Diluent + Bailout on a rebreather. The role decides when the planner may switch to the gas and which ppO₂ limit applies to it by default. | Back Gas |
| ppO₂ Limit (bar) | The oxygen partial pressure you will accept on this gas, which sets the depth it becomes available. Left alone, the planner uses the limit its role implies: 1.4 bar for a back gas or diluent, 1.5 bar for travel gas, 1.6 bar for deco and bailout. | The role’s own limit |
| Switch Depth (m) | The depth at or below which this gas becomes available on the ascent. The planner switches at or shallower than it, never deeper. Leave it empty on a back gas, which is breathed from the surface down. | Empty |
| Diluent Switch Depth (m) | The same, for a rebreather diluent. Left empty on an offboard diluent, the planner works it out from the diluent’s own limit. Anything you enter is held to that limit. | Empty |
| Drop Depth (m) | An extra ceiling on where a stage or drop cylinder is usable, on top of the one its ppO₂ implies. | Empty |
A gas breathable both on the loop and off it carries two ppO₂ limits, and it is the off-the-loop limit that decides whether the gas is a real bailout at depth. See Mixes and roles.
Breathing rates
| Setting | What it does | Where the planner starts |
|---|---|---|
| Working SAC (L/min) | Your surface breathing rate, applied to descent, bottom time and open-water ascent. | 15 L/min |
| Deco SAC (L/min) | The same, applied to decompression stops. | 12 L/min |
Both accept 5 to 40 L/min. See Gas consumption.
Decompression
| Setting | What it does | Where the planner starts |
|---|---|---|
| Algorithm | Which model computes the schedule: Bühlmann ZHL-16C, Thalmann E-L, VPM-B, Hybrid OC, DiveLogic Frontier or Thalmann GF Calibration. Each is described on Algorithms. | Bühlmann ZHL-16C |
| Parameter Set | Which Thalmann parameter set to use. Appears only when the algorithm involves Thalmann. | VVal-79 (Air/N₂-O₂) |
| Conservatism | VPM-B’s conservatism step, 0 to +5. VPM-B is not implemented, so this changes nothing. | 0 |
| Bühlmann Weight | On the two hybrid models, how the two models’ opinions are balanced, shown as a split such as “50 % Bühl / 50 % Thal”. You may set it between 10 % and 90 %. | 50 % |
| GF Low | How much of the model’s allowance you use at the deepest stop. Lower it and the first stop moves deeper. | 40 |
| GF High | How much you use at the surface. Lower it and the shallow stops grow. | 70 |
| GF presets | Three ready pairs: Conservative 30/70, Standard 40/85, Aggressive 50/95. Choosing one fills both fields; you can then edit either. | None selected |
Gradient factors govern Bühlmann and the Bühlmann half of a hybrid, and do nothing under Thalmann. On GF Calibration the two fields are replaced by read-only Fitted GF Low and Fitted GF High readouts. See Gradient factors.
Stop Settings
| Setting | What it does | Where the planner starts |
|---|---|---|
| Min Stop Time | The shortest stop the planner will schedule, and the clock it counts stop time on: 10 seconds, 30 seconds or 1 minute. | 1 minute |
| Stop Increment | The spacing of the stop grid; every stop sits on a multiple of it. Anything from 1 m to 6 m. | 3 m |
| Last Stop Depth | The shallowest stop you will hold, from 3.0 m to 9.0 m in half-metre steps. From here you ascend to the surface at the final ascent rate. | 6 m |
Air Breaks
Off unless you turn them on. Once running, you alternate a stretch on the decompression gas or setpoint with a stretch on the break gas or a lowered setpoint, until the obligation clears.
| Setting | What it does | Where the planner starts |
|---|---|---|
| Air Breaks | On or Off. | Off |
| CNS Trigger | Start cycling once the CNS clock reaches this percentage. Clear it to switch this trigger off. | 80 % |
| Runtime Trigger | Start cycling once runtime reaches this many minutes. Clear it to switch this trigger off. | Empty |
| Deco Interval | Minutes on the decompression gas or setpoint between breaks. | 20 min |
| Break Duration | Minutes on the break gas or setpoint per break. | 5 min |
| Break Gas | Which of your gases you breathe during a break. On a rebreather this is a bailout gas breathed off the loop. | None |
| Break Setpoint | On a rebreather, a lowered loop ppO₂ for the break instead of switching gas. Between 0.2 and 1.6 bar. Only used if no break gas is chosen. | Empty |
At least one trigger must be set for the cycle ever to start. If the break gas or a duration is wrong, air breaks switch themselves off and say so rather than failing the plan. See Air breaks.
Descent & Ascent
Descent is a list of segments, shallowest first; the last always runs to max depth. Add a segment to slow down over the last stretch.
| Setting | What it does | Where the planner starts |
|---|---|---|
| To | The depth this segment ends at. The final segment reads Max Depth and is not editable. | One segment, straight to max depth |
| Rate (m/min) | How fast you descend on this segment. Above 20 m/min the planner warns. | 20 m/min |
Ascent is always three phases, one for each part of the return.
| Setting | What it does | Where the planner starts |
|---|---|---|
| Max Depth → First Stop | Open-water ascent off the bottom. Above 10 m/min the planner warns. | 9 m/min |
| First Stop → Last Stop | Movement between stops. Above 6 m/min the planner warns. | 3 m/min |
| Last Stop → Surface | The final ascent. Above 3 m/min the planner warns. | 1 m/min |
Rates change the schedule as well as the clock. See Descent and ascent rates.
Environment
| Setting | What it does | Where the planner starts |
|---|---|---|
| Water Type | Salt Water or Fresh Water. Salt water is denser, so a given depth is a slightly higher pressure, and the schedule is slightly longer. | Salt Water |
| Altitude (m) | Height of the dive site above sea level. Lower surface pressure means every ceiling sits deeper and every stop runs longer. | 0 m |
See Environment.
CCR Settings
Appears only in CCR mode.
| Setting | What it does | Where the planner starts |
|---|---|---|
| Descent Setpoint (bar) | The loop ppO₂ from the surface down. | 0.7 bar |
| Working Setpoint (bar) | Takes over on reaching max depth, and stays in effect through the ascent. | 1.3 bar |
| Decompression Setpoint (bar) | Takes over from the first mandatory stop onward, overriding whatever was active. | 1.3 bar |
| Custom Depth Setpoints | Extra setpoints that take effect at a depth you name. Add as many as you need; a deeper one wins where two overlap. | None |
Every setpoint runs from 0.2 to 1.6 bar in steps of 0.05. A value outside 0.4 to 1.6 bar is quietly pulled back to the nearest of those bounds before the schedule is computed. See Setpoints.
| Setting | What it does | Where the planner starts |
|---|---|---|
| Working SAC (L/min) | The open-circuit breathing rate bailout is sized on during the working part of a bailout ascent. | 45 L/min |
| Bailout SAC (L/min) | The open-circuit rate used once the bailout ascent settles onto its stops. | 25 L/min |
| Scrubber Duration | The rated life of your scrubber, in minutes. Leave it empty and no scrubber tracking runs. Entering it warns at 60 and 30 minutes remaining and raises an error if the dive overruns; it never changes a stop. | Empty |
See Bailout planning and Scrubber tracking.
ICD Safety
Isobaric counterdiffusion limits for gas switches. The controls appear once a gas in the plan carries helium. Every one is advisory: a violation is reported against the plan and the schedule is computed regardless.
| Setting | What it does | Where the planner starts |
|---|---|---|
| N₂ Fraction Increase | Enables the check on how far the nitrogen fraction jumps across a switch. | Enabled |
| Max N₂ Increase (% pts) | How far it may jump before the check fires. | 20 percentage points |
| He Fraction Decrease | Enables the check on how far the helium fraction falls. | Enabled |
| Max He Decrease (% pts) | How far it may fall. | 15 percentage points |
| ppN₂ Increase | Enables the check on the jump in nitrogen partial pressure at the switch depth. | Enabled |
| Max ppN₂ Increase (bar) | How far it may jump. | 0.5 bar |
| ppHe Decrease | Enables the check on the fall in helium partial pressure. | Enabled |
| Max ppHe Decrease (bar) | How far it may fall. | 0.5 bar |
| Switch at Ceiling | Block or Allow. Blocking flags a switch made at or above the current decompression ceiling. | Block |
| EAD Consistency | Enables the check on two gases that narcose very differently. | Enabled |
| EAD Tolerance (m) | How far apart their equivalent air depths may be before the check fires. | 2 m |
See ICD safety.
Read next
- Creating a plan takes the same settings in the order you fill them in.
- Every number the planner gives you covers what these settings produce.
- Warnings and errors lists every message these settings can raise.