Cave Diving Cheat Sheet

The key takeaways for beginners – the five golden rules, the guideline as your way back and calm technique against panic and lost visibility.

The 5 golden rules

Rule	In short
Training	Specific cave training is the biggest safety factor – nearly all deaths involve untrained divers.
Guideline	Constant contact to the exit – your substitute eyes the moment visibility is gone.
Thirds rule	One third in, one third out, one third reserve – standard since 1980, never negotiable.
Depth/gas mix	Choose a gas mix matched to the planned depth – standard air has clear limits.
Light	3-light rule: a primary light plus two independent backups.

Cavern vs. cave

Cavern: The daylight zone with visual contact to the exit – almost every training starts here.
Cave: True darkness with a mandatory guideline – its own training stage, nobody starts straight at depth.
Train in stages: Cavern, intro, cave – each stage with minimum dive counts between them, instead of transferring experience from elsewhere.

The 3 golden technique rules

Factor 1: Never let go of the line

Concept: The guideline is your substitute eyes when visibility is gone – contact never breaks, even when switching hands only the hand changes. Tip: Train touch-contact with your eyes closed until the grip is automatic. Arrows point to the exit, cookies mark your own entry point.

Factor 2: Kick horizontal against silt-outs

Concept: A classic flutter kick pushes water downward and stirs up sediment within seconds – then visibility is gone, not just for you. Tip: Establish the frog kick: the water thrust goes backward, not down. Scale it down to a modified frog kick in tight passages.

Factor 3: Stop-breathe-think-act against the panic chain

Concept: Panic rarely strikes suddenly – it builds from a chain of small problems, and stress raises breathing and CO2 in a self-reinforcing loop. Tip: At any problem, stop first, breathe deliberately, assess the situation, only then act – the standard response in any serious cave training.

Emergency: lost line or buddy

Step	What matters
Stop immediately	Hold position instead of searching wildly – the first ten seconds decide the outcome.
Shotgun pattern	Set two fixed points, search outward like spokes, return to centre before each new direction.
Search budget	Plan at least double your exit gas for the buddy search, with a fixed turnaround limit.
Drill the protocol	Train regularly in zero visibility with real surprise, until the reaction runs automatically.

Gas planning: when a third is not enough

The sixths rule for beginners: Limit your penetration to a sixth while your own consumption under stress is still hard to judge – almost double the reserve.
Factor in current: Estimate consumption separately for each direction – the more expensive direction sets your turn pressure.
Write down your turn pressure: Calculate and note it before the dive, never work it out underwater – stress makes mental math worse.

Pro tip: Crystal-clear water makes the danger less visible, not smaller – the five golden rules apply in a cenote just as much as in a murky quarry. Drill the real emergency until stop-breathe-think-act beats panic to the punch.