Turnaround Gas Pressure Calculator

Reconcile actual starting pressure minus independently qualified outbound pressure budget, retain signed difference to approved reserve. Does not choose thirds, gas plan, turn trigger or safe cave-dive/decompression limit.

Description

Recorded dive pressure can be reconciled with an independently approved outbound budget and reserve.

Recorded dive pressure can be reconciled with an independently approved outbound budget and reserve.^[1]

The subtraction preserves that supplied plan without selecting a turn rule or evaluating gas adequacy.

When to use Turnaround Gas Pressure Calculator

Use this tool to obtain conditionalRecordedTurnPressureBar, signedTurnMinusCallerReserveBar from the supplied records using the stated calculation. Establish the survey or observation scope, reference frame, units and independently applicable calibration or qualified plan.

How to use Turnaround Gas Pressure Calculator and understand its results

Establish the survey or observation scope, reference frame, units and independently applicable calibration or qualified plan.
Enter actualRecordedStartingPressureBar, callerIndependentlyApprovedOutboundPressureBudgetBar, callerIndependentlyApprovedReservePressureBar, using the field meanings and rules below, then run the tool.
Read result.conditionalRecordedTurnPressureBar, result.signedTurnMinusCallerReserveBar. Use the units and sign conventions below, and review any unknown records separately.
Correct any reported input issue and run again. Before using a successful result, check the stated units, signs, reference scope and observation coverage.

Input field	Meaning	Value type	Requirement
actualRecordedStartingPressureBar	Actual recorded starting pressure bar	number	Required
callerIndependentlyApprovedOutboundPressureBudgetBar	Caller independently approved outbound pressure budget bar	number	Required
callerIndependentlyApprovedReservePressureBar	Caller independently approved reserve pressure bar	number	Required

Require nonnegative starting pressure, approved outbound budget and approved reserve in bar. Outbound budget must not exceed starting pressure. Subtract budget from start, then subtract reserve from that conditional pressure. A negative reserve margin is returned unchanged. No turn trigger, reserve or thirds rule is selected.

conditionalTurnBar=startBar−budgetBar; marginBar=conditionalTurnBar−reserveBar

Use the matching field units and the exact boundary, ordering and reference rules above.

Output field	Meaning	Value type
result	Qualified observed calculation or explicit reference	object
result.conditionalRecordedTurnPressureBar	Conditional Recorded Turn Pressure Bar	number
result.signedTurnMinusCallerReserveBar	Signed Turn Minus Caller Reserve Bar; preserve the subtraction order and sign defined in the mechanics	number

json

{
  "input": {
    "actualRecordedStartingPressureBar": 200,
    "callerIndependentlyApprovedOutboundPressureBudgetBar": 60,
    "callerIndependentlyApprovedReservePressureBar": 80
  },
  "output": {
    "result": {
      "conditionalRecordedTurnPressureBar": 140,
      "signedTurnMinusCallerReserveBar": 60
    }
  }
}

Limitations and assumptions

The actual observation coverage, calibration and qualified plan determine applicability. A numerical result does not establish survey accuracy, route suitability, atmosphere conditions or equipment adequacy beyond the declared comparison.

Missing required fields, unknown fields, wrong types and violated rules return input issues. Numeric values and outputs must be finite. Extremely large composite outputs are rejected.

Alternative or Complementary methods

For a related step, use Cave Dive Rule of Thirds Gas Planner: A cave-dive thirds rule belongs to a qualified gas-management protocol and configuration. For a complementary comparison, use Rock Bottom Gas Pressure Calculator: A rock-bottom gas reference belongs to a qualified emergency model and team configuration.

References

Turnaround Gas Pressure Calculator — tool.io

Similar or alternative tools

Cave Dive Rule of Thirds Gas Planner
A cave-dive thirds rule belongs to a qualified gas-management protocol and configuration.
Rock Bottom Gas Pressure Calculator
A rock-bottom gas reference belongs to a qualified emergency model and team configuration.