Settings

The Settings page gathers every calculation and display parameter. These settings are stored on your device and serve every new dive. Remember to click Save after changing them.

Language and theme

• Language: pick from French, English, German, Spanish, Italian, Polish.
• Theme: dark or light.

Divers and dive site

• Divers: type the default names, comma-separated. They are carried over automatically to the plan and to the printed PDF.
• Dive Site: name of the site, carried over to the plan (for instance "Blue Hole, Dahab").

Algorithm

Choose the decompression model:

• ZHL-16C: the most widespread in technical diving (recommended).
• ZHL-16B: a slightly more permissive variant on some compartments.

Gradient factors (GF)

Gradient factors drive how conservative the decompression is.

• GF Low: the fraction of supersaturation tolerated at depth. It applies at the deepest ceiling of the dive; the lower it is, the deeper the stops begin.
• GF High: the fraction tolerated when leaving the water. The lower it is, the more conservative the final decompression.

Between the two, the gradient factor varies linearly with pressure, as it does in Subsurface. The detail of the calculation is on the Ascent calculation page.

Set each value with its slider (from 10 to 100 %). The value is shown as you drag.

GF presets

You can store GF Low / GF High pairs as presets, to call them up quickly from the Plan page.

• Existing presets are shown as badges. Click the X of a badge to remove it.
• Click Add preset to create one: give it a name (generated automatically if left empty), then its GF Low and GF High values.

Rates and stops

• Descent: descent rate (m/min).
• Ascent: ascent rate from the bottom (m/min).
• Between stops: ascent rate from one stop to the next (m/min).
• Last stop ascent: ascent rate from the last stop to the surface (m/min).
• Last stop: depth of the last stop, 3 m or 6 m.
• Safety stop: the time, in minutes, held at the last stop when the dive owes no decompression at all (3 min by default, 0 to hold none). That stop is marked "Safety" in the table and is never counted as a decompression obligation. On a dive with stops it is not added: the last decompression stop is enough.
• Descent time included: when on, the descent time counts inside the segment time. A segment shorter than its own descent is refused, with a message giving the descent time.
• Gas switch duration: time set aside for each gas change (min).
• Switch gas at deco stop only: when on, a change happens only at a stop. When off, the change happens as soon as the MOD allows, which is more optimal.

A field left empty, or a value outside its range, is refused and put back to the stored value: a setting can no longer be remembered empty.

Consumption (RMV / SAC)

Surface equivalent consumption is what gas requirements are estimated from.

• Bottom: consumption on the bottom (L/min).
• Deco / Bailout: consumption during decompression or on bailout (L/min).

In rebreather mode, two more settings appear (see CCR mode):

• Stress RMV: the raised consumption under stress.
• Stress until: how far to apply the stress consumption (first stop, gas switch or surface).

ppO2 limits

• Working: maximum oxygen partial pressure on the bottom (typically 1.4 bar).
• Deco: maximum oxygen partial pressure during decompression (typically 1.6 bar).

Environment

• Gas temp.: lung temperature used for the gas density calculation (around 35 °C).
• Water type: the salinity of the site, which changes the pressure actually felt at a given depth, and therefore the length of the stops. Four reference points are offered, each with its density: fresh water (10000 g/l), brackish water (10150 g/l), salt water (10300 g/l, the default) and Red Sea (10400 g/l). The last entry, Custom density, brings up a field where you type the density of the site directly, from 9500 to 12500 g/l; a value outside those bounds is refused and flagged under the field.
• Altitude: altitude of the dive site (m), for altitude lake diving.

Under the selector, a line recalls what the chosen water stands for, for instance 10300 g/l - 9.90 m/bar: its density and how many metres of water weigh one bar. The detail, and the measured effect on the stops, is on the Water type and salinity page.

These values have a default here in the settings, but can be adjusted dive by dive from the Plan page. They are stored with the saved plan: a saved plan keeps the water type and the altitude it was computed for. Plans saved before that setting existed carry none; they are read back as computed at sea level in salt water, and not with the environment currently on screen. See New pressure model.

Safety alerts

You can turn each family of alerts on or off (for experienced divers):

• Narcosis alerts (END): warn when the equivalent narcotic depth gets high.
• Density alerts (CO2): warn when gas density gets too high (laboured breathing, CO2 retention).
• ICD alerts (inner ear): warn when helium drops sharply at a gas change.

CCR mode

Turns on closed circuit rebreather mode and its options (fixed or dynamic setpoint mode, bailout). See the dedicated CCR mode page.

• Finish the dive on 100% oxygen: flushes the loop with pure oxygen during the ascent of every rebreather dive, and leaves it there to the surface. The depth (6 m by default) and the flush duration (1 min) are set just below, and the resulting ppO2 is shown right after - 1.62 bar at 6 m at sea. Nothing to declare as a gas: the oxygen cylinder goes without saying on a rebreather.

PDF export

• Include dive profile: adds the profile chart to the PDF. Turn this off to fit on a single A4 page.

School mode

School mode compares several GF presets side by side on the same profile chart.

• Turn school mode on.
• Select up to three presets to compare.
• Adjust the chart scale if needed (line thickness and font size).

The compared curves then appear on the Profile page.

Units

Choose the system of units:

• Metric: metres and bar.
• Imperial: feet and psi.

Reset

The Reset to Defaults button puts every parameter back to its default value, after confirmation.