NagiFreediving · Japan

03 · Safety

Freediving Safety Rules

Freediving can be very safe or very dangerous — the difference is a handful of simple rules.

The headline first: recreational freediving done by the rules is a remarkably safe sport — and the vast majority of accidents come from breaking the same few basic rules. Read this page and you’re already ten times safer than most self-taught divers.

Rule one: never dive alone

No exceptions — not in shallow water, not because you’re a strong swimmer. Freediving’s main risk (blackout) is one you cannot rescue yourself from; a trained buddy beside you is the entire difference. This is why proper courses treat rescue skills as core curriculum.

Rule two: one up, one down

How the buddy system actually works: while one dives, the other watches from the surface — until the diver surfaces, completes recovery breathing and signals OK. Only then do you swap. Two people underwater at the same time is the same as no buddy at all.

Rule three: no hyperventilation

Fast, deep breathing before a dive adds no oxygen — it just switches off your CO₂ alarm so blackout arrives without warning. Calm breathing is the best preparation (see the breathing guide).

Know LMC and blackout

Sounds scary? In a proper course these are standard procedures drilled in the pool until they’re muscle memory. Knowing exactly what to do is what real peace of mind feels like.

The other iron rules


Practicing these rules hands-on is the heart of the AIDA2 course.

04 · Freediving Gear: A Beginner's Guide → ← All topics