Dalton vs Deep Frontier Dive Tools

Know your gas. Trust your numbers. Dalton is the gas calculator that shows its work. Every result is verified against PADI Nitrox Tables, TDI Trimix Tables, and Shearwater manuals. Every formula is published with step-by-step derivations and source citations. No black boxes. GAS CALCULATIONS - MOD (Maximum Operating Depth): Find the safe depth limit for any gas mix based on your ppO2 tolerance - Equivalent Air Depth: Calculate nitrogen loading equivalents for nitrox decompression planning - Equivalent Narcotic Depth: Determine narcotic effects at depth for trimix planning - Best Mix: Find the optimal oxygen percentage for your target depth - Gas Properties: Calculate density, partial pressures, and breathing resistance at depth DIVE PLANNING - Return Number (Dalton Pro): Gas volume required for safe ascent — rule of thirds, fourths, or custom reserve fractions. The overhead environment gas management tool most divers do on paper or skip entirely - Dive Profile Advisor (Dalton Pro): Plan multi-level dives with gas switches and depth segments - Bottom Time Calculator (Dalton Pro): Determine available bottom time based on gas supply and consumption Dalton Pro tools require a one-time in-app purchase. All gas calculation tools are free. FORMULA REFERENCE Tap any result to see the full formula derivation with source citations. Dalton is the only mobile gas calculator that publishes every formula it uses. Teach the math. Show the math. SHARE YOUR CALCULATIONS Share any result as a URL with a QR code. Recipients with Dalton installed open the calculation directly in the app. Everyone else sees a web preview with the full results. Dalton Pro tool links show a result summary before the in-app purchase prompt -- useful for team briefings where not everyone has the app. Export formula cards as branded images. Send your gas plan to a buddy, post it in the group chat, or print it for the dive briefing whiteboard. One calculation, shared with the entire team in seconds. HOME SCREEN AND LOCK SCREEN WIDGETS - Quick Launch: A 2x2 grid that opens MOD, Best Mix, EAD/END, or Gas Properties with a single tap. No navigating through menus at the fill station - Quick MOD Reference: Pre-computed MOD for your selected gas mix, available on home screen and lock screen in circular, rectangular, and inline formats. Glance at your lock screen and see your MOD without opening the app - Both widgets are free - All values are pre-computed inside Dalton. No calculation logic runs in the widget extension SAFETY-FIRST DESIGN - Three-tier safety warnings tied to recognized physiological thresholds - Gas-density guidance from Anthony and Mitchell research: preferred below 5.2 g/L, caution from 5.2 to below 6.2 g/L, danger at 6.2 g/L and above - Configurable safety limits with ppO2 range from 1.2 to 1.6 bar - Standard gas mix presets: Air, EAN32, EAN36, and common trimix blends - Full gas range: air, nitrox, and trimix including hypoxic blends to 300m - All calculations work offline; anonymous crash and release-health diagnostics may be sent when online - No subscriptions, no ads, no account creation Every calculation is verified. Every result is reliable. A Tools for Divers, LLC product

Deep Frontier Dive is a decompression planner for trained technical divers. Plan open-circuit and CCR dives with two validated models, complete gas planning, and the contingencies that matter — on iPhone and iPad, fully offline, in metric units. TWO DECOMPRESSION MODELS • Bühlmann ZHL-16C with gradient factors — presets or fully custom GF low/high • VPM-B and VPM-B/GFS with conservatism levels 0–4 • Cross-validated against published reference schedules OPEN CIRCUIT AND CCR • Open-circuit plans with automatic gas switches at sensible depths — ppO2 hard-capped at 1.6, lean deco mixes at 1.4 • CCR plans with bottom and deco setpoints and diluent control • Full open-circuit bailout schedules from your carried bailout gases — never assumed, always checked, with clear warnings when coverage or volume falls short GAS PLANNING • Per-cylinder consumption from your bottom and deco SAC rates • Reserve strategies including rule of thirds • Minimum gas / rock bottom for a two-diver problem at depth • Lost-gas contingencies: every deco gas lost, replanned, and checked against the remaining volumes DIVE DAYS • Repetitive dives with surface intervals • Tissue and bubble state carried from dive to dive • Cumulative CNS and daily OTU totals WARNINGS THAT MATTER ppO2, END, gas density, isobaric counterdiffusion (rule of fifths), CNS and OTU — flagged as caution or danger before you get wet. GAS TOOLS MOD, best mix, EAD, END, gas density and equivalent air-density depth, SAC calculator, and partial-pressure blending worksheets. BUILT FOR THE FIELD • Altitude diving support • Three configurable ascent-rate phases: bottom to deco, during deco, deco to surface • Salt and fresh water • Saved plans — editable, duplicable, never locked • Runtime tables with depth, duration, runtime, gas and ppO2 for every level • Depth-profile chart with stops and gas-switch markers • Works completely offline. No account, no ads, no tracking. FREE AND PRO Open-circuit Bühlmann planning, the gas plan and saved plans are free forever. A single one-time purchase — Deep Frontier Dive Tools Pro — unlocks CCR planning, VPM-B, lost-gas contingencies, dive days and the gas tools. No subscription. IMPORTANT This app is a planning tool for trained technical divers. It is not a substitute for formal training, a dive computer, or your own judgement. Decompression planning involves inherent uncertainty: always validate schedules against your training and agency procedures, plan adequate reserves, and dive entirely at your own risk.