Safety Disclaimer
Everything on ScubaSetup is researched education, not dive instruction. The calculators are planning and teaching tools, never a substitute for certified training, published dive tables or a dive computer, and no output from any of them is a dive plan. Scuba diving carries a real risk of decompression sickness, oxygen toxicity, barotrauma and drowning.
Read this in full before you use anything on this site
These calculators are for planning and education only. They are not a substitute for certified dive training, published dive tables, or a dive computer. Always dive within the limits of your certification and verify every plan with your own computer and a qualified instructor or divemaster.
That paragraph appears on every calculator and every dive planning page on ScubaSetup.com, and it is the most important sentence we publish. This page explains what sits behind it, because a disclaimer that is only read as legal boilerplate has failed at its job.
What is this site, and what is it not?
ScubaSetup.com publishes researched guidance and education about scuba equipment and the arithmetic of dive planning. It is written for certified recreational divers who want to understand the reasoning rather than be handed a conclusion.
It is not dive instruction. It is not a training agency, it is not affiliated with one, and reading it does not qualify anybody to do anything. Recreational scuba diving is taught in person, with supervised dives, by an instructor who can see you in the water and correct you. Nothing published on a web page can substitute for that, and this site never positions itself as if it could.
What are the calculators, precisely?
They are teaching instruments. Each one performs a standard piece of dive arithmetic, prints the formula it used, states the assumptions it made, and warns when an input takes you outside recreational limits. That design is deliberate: this audience is trained and can check the working, and a tool that shows its working can be checked while a black box cannot.
What they are not:
- They are not dive plans. A maximum operating depth is one input into a plan. A rock bottom figure is one input into a plan. A plan is made by a trained diver for a specific dive with a specific buddy in specific conditions.
- They are not dive tables. Published tables come from a training agency, are taught with a method, and carry rules about repetitive dives, surface intervals and altitude that a web form does not enforce.
- They are not a dive computer. A computer models your actual profile continuously, second by second, and adjusts. A calculator answers one question about one set of numbers you typed in.
- They do not know your dive. They cannot see the current, the visibility, your fitness on the day, your hydration, your fatigue, the temperature, or your buddy.
Where the numbers disagree, the order of authority is: your training, then your agency's published materials, then your own computer, then anything on this site. If a figure here contradicts your instructor, your instructor is right and we want to hear about it.
Why do no-decompression limits vary, and which one is right?
Published no-decompression limits differ between training agencies and between the algorithms that computers run, sometimes by tens of minutes on the same profile. This is not a mistake by anybody. Decompression models are mathematical approximations of a physiological process that is not fully understood, and different models make different conservative choices.
Two consequences follow, and both are practical rather than academic:
- Any table we publish is labelled with its source, usually the PADI Recreational Dive Planner for air with no repetitive dive, and it sits under a prominent warning that limits vary and that your own computer supersedes it.
- A buddy pair on different computers runs the dive on the more conservative of the two. Not the average, not yours because you bought it more recently. The more conservative one.
Decompression sickness also occurs within published limits. A limit is a statistical boundary, not a guarantee, and the factors that push an individual dive across it, including cold, dehydration, exertion, fatigue and individual physiology, are invisible to every model.
Why does gear never substitute for training?
Because every piece of equipment on this site assumes a set of skills, and it fails silently if those skills are missing. A surface marker buoy deployed from depth requires a taught procedure. A drysuit is a second buoyancy device with failure modes that will invert an untrained diver. A computer that supports trimix will happily display a profile that will hurt you.
So we state it as a rule rather than a caveat: buying an item does not qualify you to use it, and no product on this site extends the limits of your certification. Where a piece of gear implies training, the page says which training. Where a topic needs a course, the page says so and stops.
What will this site not publish, and why?
We do not publish procedures for decompression diving, technical diving, cave and wreck penetration, solo diving or rebreather diving. We explain what each discipline is, why it requires formal training, and where that training comes from, and then we stop.
The reasoning is not legal caution. It is that reading confers no competence, and a procedure written for a general audience will be read by someone who has not been taught the failures it assumes they can handle. A gas switch schedule is not dangerous because it is complicated, it is dangerous because executing it wrong at depth is unforgiving and because recognising that it has gone wrong is itself a trained skill. The technical diving page sets this out in full.
For the same reason, the calculators stop at recreational limits and warn rather than calculating when an input crosses one.
What are the actual risks of scuba diving?
Stated plainly, because a disclaimer that lists no risks is not informing anybody:
| Risk | What it is | Where it appears on this site |
|---|---|---|
| Decompression sickness | Inert gas coming out of solution as bubbles during or after ascent | Every page touching no-decompression limits or ascent |
| Oxygen toxicity | Central nervous system effects at elevated oxygen partial pressure | The nitrox MOD calculator and every nitrox page |
| Barotrauma | Pressure injury to ears, sinuses or lungs, including lung overexpansion | Ascent rate and buoyancy pages |
| Drowning | The outcome most other failures lead to if uncorrected | Gas planning, weighting and equipment redundancy pages |
| Nitrogen narcosis | Impaired judgement at depth, which nitrox does not reduce | The nitrox pages, which say so explicitly |
| Entanglement | Line, net or monofilament, addressed by a cutting tool you can reach | Every complete setup on the site |
Diving inside the limits of your certification, with a buddy, on a plan you made before you got in the water, with gear that has been serviced, reduces every one of those substantially. None of them is eliminated by equipment or by reading.
Product information and specifications
Every depth rating, cylinder capacity, algorithm name, nitrox ceiling and price on this site is the manufacturer's published figure at the time we recorded it, unless stated otherwise. We do not test gear in person and we never claim to. Specifications change between hardware revisions and firmware versions, and prices and availability change constantly, so confirm anything that matters against the manufacturer's current documentation and the retailer page before you buy.
Where we could not confirm a figure against the maker's own documentation, we omit it rather than guess. If a specification here is wrong, tell us through the contact form with a link to the documentation, and we will fix it.
In an emergency
Contact emergency services and a diving medical emergency hotline. Do not consult a website. Symptoms of decompression illness can appear during a dive, immediately after, or hours later, and can be subtle: unusual fatigue, joint or muscle pain, tingling or numbness, weakness, dizziness, breathing difficulty or confusion. If you are unsure whether symptoms are dive related, treat them as if they are and speak to a physician trained in diving medicine.
Limitation of liability
ScubaSetup.com is provided on an "as is" basis, without warranty of any kind, express or implied. We make no warranty that the information here is complete, current or accurate, and we specifically disclaim any warranty of fitness for a particular purpose. To the fullest extent permitted by law, ScubaSetup.com and its authors accept no liability for any loss, injury or damage arising from the use of this site, from reliance on anything published here, or from any product purchased through a link on it.
By using this site you accept that scuba diving is an activity carrying inherent risk of serious injury and death, that you are responsible for diving within the limits of your own training and certification, and that you will verify every plan against your own computer and a qualified instructor or divemaster. Full terms are on the terms of service page.
Related pages
Frequently asked questions
Can I plan a dive with the calculators on this site?
No. You can use them to learn the arithmetic, to sanity check a figure, and to understand what your computer is showing you. A dive plan is made by a trained diver using their own computer, their agency's tables and the conditions on the day, with a buddy who has checked it. Every calculator here prints its formula and assumptions precisely so that you can check our work rather than trust it.
Why do your no-decompression limits differ from my computer?
Because published limits vary between training agencies and between decompression algorithms, sometimes by tens of minutes on the same profile. The figures we publish are labelled with their source, usually the PADI Recreational Dive Planner for air with no repetitive dive. Your computer models your actual multi level profile continuously rather than pricing the whole dive at maximum depth, and it supersedes any table, including ours.
Is a dive computer enough to keep me safe?
No. A computer models inert gas loading using assumptions about an average body, and it cannot see your hydration, fatigue, temperature, workload, patent foramen ovale status or how fast you actually ascended. Decompression sickness occurs within published limits. A computer is an instrument that makes a trained diver better informed, and it is not a safety device that makes an untrained diver safe.
Why will you not publish technical diving procedures?
Because reading a page confers no competence, and any procedure written for a general audience will be read by someone who has not been taught the failures it assumes they can handle. Decompression diving, cave and wreck penetration, solo diving and rebreathers all require formal training with an instructor and supervised dives. We explain what they are and where to learn them, and we stop there deliberately.
What should I do if I think a figure on this site is wrong?
Tell us immediately through the contact form, with the page, the figure and your working. Corrections to dive planning math go to the front of the queue ahead of every other message, and we publish the fix rather than quietly editing it. In the meantime, treat your own training, your agency's materials and your computer as authoritative over anything published here.
What should I do in a diving emergency?
Contact emergency services and a diving medical emergency hotline immediately. Do not consult a website. Symptoms of decompression illness can appear hours after a dive and can be subtle, including unusual fatigue, joint pain, tingling, weakness or confusion. If you are unsure whether symptoms are dive related, treat them as if they are and get medical advice from a physician trained in diving medicine.
How we choose: we compare published manufacturer specifications, published training agency standards, and verified owner reviews across retailers. We do not test gear in person, and every depth rating, cylinder capacity and algorithm name quoted here is the manufacturer's published figure unless we say otherwise, so confirm it on the current spec sheet before you buy. Nothing here is dive instruction, and no calculator output on this site is a dive plan. Scuba diving carries a real risk of decompression sickness, oxygen toxicity, barotrauma and drowning. Dive within the limits of your certification, verify every plan with your own computer, and buy the training before the gear that assumes it.
Logging your own SAC rate and gas plans? The Dive Kit & Air Planning Workbook is the paid version of these pages: 8 printable worksheets you fill in with your own numbers, plus the full PDF, $29.