The Gas Consumption view answers one question: does the plan fit the cylinders you carry. A line across the top repeats Working SAC and Deco SAC; change them in Work Rates.
The per-level ledger
One card per planned level, in dive order, naming the level and its gas. Six figures, all in bar except the last:
- Leaving at: what is left when you leave the level.
- Turn pressure: where you must turn the dive; the cost of reaching the next switch plus the reserve.
- To next switch: what reaching the next gas switch will cost from here.
- Reserve: held back under the reserve rule named on the card, set per gas role in Work Rates.
- Start pressure: what you began the level with.
- Runtime: where in the dive this level sits. Minutes, not bar.
Gas ledger by level
Two labels can appear. Below turn: what is left has fallen past the turn pressure, so the plan has no reserve in hand. Supply exceeded: the cylinder cannot cover the level at all, and the card takes the error tone. Missing figures mean a gas with no tank size or working pressure.
One card per gas
Each gas then gets a card of its own: name, colour, cylinder and role tags, a consumption bar, then Starting, End and Used Pressure with Remaining as a percentage, and the same four in litres where the tank size is known.
Low gas means the plan finishes on this cylinder with little in hand; Insufficient gas means it does not finish at all. Neither changes the schedule: the planner will draw an ascent your gas cannot pay for.
On a rebreather
The loop’s own gas is budgeted rather than drawn down: the oxygen and each diluent get a requirement card instead of a ledger. Under Tasks it names what the figure is made of - metabolic oxygen, the loop fill down to that cylinder’s depth, mask clears, diluent flushes, wing and drysuit - each in litres and in bar of that cylinder. Required against Available follows, with a verdict. Every diluent you carry gets a card, offboard ones included.
The tasks are the raw figures and the requirement is rounded up, so they add to slightly less than the total beside them.
A selected scenario adds its own cards for the ascent from its bail point, at the bailout rates.
A cylinder carrying the Diluent + Bailout role is shown as whichever it actually is on this dive. Where the loop is flown on it - the whole dive on a single-cylinder unit, or just the ascent once you are shallower than its diluent limit - it gets a requirement card like any other diluent, charged at the depth it is switched to. Carried as a spare the loop never flies, it gets a ledger instead, holding the whole dive replayed open circuit as a stock check on that one cylinder.
Whether such a cylinder can also carry you out is a separate question, and bailout scenarios are where it is asked. Select one and the same cylinder is charged the loop gas you spent before the bail point plus the ascent from it; a Loop use line names the first part, inside the total, not on top of it.
Next
The tissue saturation view, and Consumption for how a surface rate becomes litres at depth.