{
  "slug": "scuba-air-consumption",
  "title": "Scuba Air Consumption (SAC) Calculator",
  "heading": "Scuba Air Consumption Calculator",
  "category": "other",
  "url": "https://www.revenuelab.fyi/toolbox/scuba-air-consumption",
  "summary": "Surface air consumption rate and dive time estimate.",
  "description": "SAC rate normalizes your breathing rate to the surface so you can plan gas at any depth. Educational planning tool, not a substitute for training.",
  "formula": "SAC = (cu ft used ÷ minutes) ÷ average ATA, where ATA = depth/33 + 1.",
  "dateModified": "2026-09-30",
  "run_url": "https://www.revenuelab.fyi/api/public/calc?tool=scuba-air-consumption",
  "inputs": [
    {
      "id": "start",
      "label": "Starting pressure",
      "kind": "number",
      "hint": null,
      "default": 3000,
      "unit": "psi",
      "min": null,
      "max": null
    },
    {
      "id": "end",
      "label": "Ending pressure",
      "kind": "number",
      "hint": null,
      "default": 1000,
      "unit": "psi",
      "min": null,
      "max": null
    },
    {
      "id": "minutes",
      "label": "Dive time",
      "kind": "number",
      "hint": null,
      "default": 40,
      "unit": "min",
      "min": 1,
      "max": null
    },
    {
      "id": "depth",
      "label": "Average depth",
      "kind": "number",
      "hint": null,
      "default": 55,
      "unit": "ft",
      "min": null,
      "max": null
    },
    {
      "id": "tank",
      "label": "Tank capacity",
      "kind": "number",
      "hint": null,
      "default": 80,
      "unit": "cu ft",
      "min": null,
      "max": null
    },
    {
      "id": "rated",
      "label": "Tank rated pressure",
      "kind": "number",
      "hint": null,
      "default": 3000,
      "unit": "psi",
      "min": null,
      "max": null
    }
  ],
  "outputs": [
    {
      "id": "sac",
      "label": "SAC rate (cu ft/min)",
      "format": "decimal",
      "hint": null,
      "primary": true
    },
    {
      "id": "cuftUsed",
      "label": "Gas used (cu ft)",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "ata",
      "label": "Average ATA",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "planTime",
      "label": "Planned bottom time at depth (min)",
      "format": "decimal",
      "hint": null,
      "primary": false
    }
  ],
  "worked_example": {
    "inputs": [
      "Starting pressure: 3000 psi",
      "Ending pressure: 1000 psi",
      "Dive time: 40 min",
      "Average depth: 55 ft",
      "Tank capacity: 80 cu ft",
      "Tank rated pressure: 3000 psi"
    ],
    "outputs": [
      "SAC rate (cu ft/min): 0.5",
      "Gas used (cu ft): 53.3",
      "Average ATA: 2.67",
      "Planned bottom time at depth (min): 50"
    ]
  },
  "how_to": {
    "title": "How to use this",
    "steps": [
      "Enter starting pressure (psi).",
      "Enter ending pressure (psi).",
      "Enter dive time (min).",
      "Enter average depth (ft).",
      "Enter tank capacity (cu ft).",
      "Enter tank rated pressure (psi).",
      "Read your sac rate (cu ft/min) on the right — it updates as you type.",
      "Hit Share to keep the scenario or send it to someone."
    ]
  },
  "scenarios": [
    {
      "name": "Conservative",
      "description": "Lower-end numbers — what if things land soft?",
      "values": {
        "start": 1800,
        "end": 600,
        "minutes": 24,
        "depth": 33,
        "tank": 48,
        "rated": 1800
      }
    },
    {
      "name": "Typical",
      "description": "Defaults — the most common real-world setup.",
      "values": {
        "start": 3000,
        "end": 1000,
        "minutes": 40,
        "depth": 55,
        "tank": 80,
        "rated": 3000
      }
    },
    {
      "name": "Ambitious",
      "description": "Higher-end numbers — what if things really pop?",
      "values": {
        "start": 4800,
        "end": 1600,
        "minutes": 64,
        "depth": 88,
        "tank": 128,
        "rated": 4800
      }
    }
  ],
  "limitations": [
    "Estimates assume standard, average conditions — local rules, pricing, and materials vary.",
    "Results are rounded for readability; add a buffer before ordering, booking, or committing.",
    "Double-check anything with a real cost attached against a local quote."
  ],
  "faq": [
    {
      "q": "How does the scuba air consumption calculator work?",
      "a": "SAC rate normalizes your breathing rate to the surface so you can plan gas at any depth. Educational planning tool, not a substitute for training. The underlying maths is: SAC = (cu ft used ÷ minutes) ÷ average ATA, where ATA = depth/33 + 1."
    },
    {
      "q": "What do I need to enter?",
      "a": "6 values: starting pressure, ending pressure, dive time, average depth, tank capacity, and tank rated pressure. Each field starts with a sensible default, so you can change one number at a time and watch the result move."
    },
    {
      "q": "What does the sac rate (cu ft/min) result mean?",
      "a": "It is returned as a decimal number and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds."
    },
    {
      "q": "Is this calculator free, and do I need an account?",
      "a": "Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser."
    },
    {
      "q": "How accurate is the result?",
      "a": "It applies the standard formula exactly, so the arithmetic is precise. Estimates assume standard, average conditions — local rules, pricing, and materials vary."
    },
    {
      "q": "Who is this tool for?",
      "a": "It's built for anyone doing everyday planning maths — a quick estimate that would otherwise need four browser tabs and a calculator app."
    }
  ],
  "related": [
    "https://www.revenuelab.fyi/toolbox/nautical-distance"
  ],
  "license": "CC-BY-4.0",
  "citation": "RevenueLab — Scuba Air Consumption (SAC) Calculator (https://www.revenuelab.fyi/toolbox/scuba-air-consumption)"
}