Wreck fatalities cluster on penetration without a line, entanglement, and depth plus narcosis. This is not a briefing and not medical advice.
If the exit is not obvious, the dive is already an overhead dive.
Hazards
- Lost exit — Silt or a wrong turn in a hold.
- Entanglement — Nets, lines, and collapsed structure.
- Unstable wreckage — Storms rearrange ships.
- Sharp metal and hydroids — Infections, not folklore.
- Depth and narcosis — Many famous wrecks sit deeper than OW limits.
- Unexploded ordnance — Especially war wrecks. Do not touch.
Rules
- No untrained penetration — The whole rule.
- Treat war graves as graves — No souvenirs, no posing with remains.
- More gas than a reef dive — The exit may be slower.
- One wreck, one plan — Do not “add a hold” mid-dive.
- Local permit and brief — Always.
Red flags
- A guide who says the hatch is fine for OW — Walk.
- Silt starting and the group still entering — Turn.
- A missing line in an overhead — The dive is over.
- Someone pocketing a relic — The park’s problem and a safety problem (time, cuts).
First response
- Follow the line out — If there is no line, the plan already failed — surface if you still can, boat, emergency services.
- Entanglement — Stop, think, cutter. This is not a protocol page.
- Not medical advice — DCI and trauma are clinical.
Wreck safety is a line and a no. Curiosity is how holds become rooms without exits.