Line and float-line tangles
Explainer · Last reviewed 2026-08-19
A tangle around a diver is an entanglement hazard rather than an inconvenience, which changes both how it is prevented and what to do when it happens.
Safety: entanglement — can cause serious injury or death.
Never dive alone, dive one up one down, and never extend a dive for a fish.
Spearfishers carry more line than they think: shooting line on the gun, a float line or reel line to the surface, and sometimes a stringer. Every one of them is a potential entanglement, and the diver's own equipment is the largest source of entanglement incidents in the discipline.
WHERE TANGLES COME FROM.
SHOOTING LINE WRAPPED UNEVENLY on the gun's line guides. It loops on release, catches on the muzzle or a band, and the shot goes wrong at the moment of firing.
FLOAT LINE LOOPING IN FRONT of the diver instead of trailing behind. Any turn, any current change, and it is around an arm or a fin.
REEL LINE PAYING OUT AROUND STRUCTURE while the diver follows a fish. This is the interaction behind most serious entanglement incidents, and it is why hole hunting is the highest-risk technique in the discipline.
SLACK LINE ANYWHERE. Line under tension behaves; slack line finds things.
THE RESPONSE. Stop. Do not thrash — movement tightens a tangle and burns the oxygen you have. Establish what is caught. Use the knife if the line cannot be cleared quickly, and cut without hesitation: line is cheap. Signal the buddy, who should already be watching.
AND THE KNIFE MUST ACTUALLY CUT. Dyneema is very difficult to cut with a dull blade, and a knife that has rusted into its sheath is not equipment.
Prevention is a habit rather than a technique
Know where every line is before descending. That is the whole of it, and it is a habit practised on every dive rather than a skill acquired once.
Wrap the shooting line under even tension. Keep the float line behind and to one side. Do not swim through your own line to reach a fish. Do not enter an opening you cannot back out of.
Use a breakaway where a fish is likely to run into structure, so the gun separates from the fish rather than the diver being connected to both.
Carry the knife where either hand can reach it, because a knife on the right calf is unreachable if the right arm is caught.
And on the surface, keep the float line managed rather than trailing loose. A large share of tangles begin at the surface between dives, where nobody is paying attention because nothing is happening.
Official guidance — why, and the sources (1)
Stated by a fisheries authority, scientific institute or recognised angling body. Authoritative, but summarising rather than demonstrating.
- BSAC diving safety guidance and annual incident report — British Sub-Aqua Club (Water-safety or diver-training authority)Relied on for: Diving safety guidance on entanglement hazards, line management and emergency cutting equipment.States this directlyCitation checked — the work exists and is described correctly
Safety
Never dive alone, dive one up one down, and never extend a dive for a fish. The full set of breath-hold essentials — training, the buddy system, conditions, equipment and visibility — is on the spearfishing safety page.
Entanglement — Can cause serious injury or death
A breath-hold diver held by their own shooting line, float line or reel line has only the remainder of one breath, and struggling tightens the tangle while spending oxygen.
What reduces it: Knowing where every line is before descending, keeping the float line clear and behind, breakaway systems near structure, a sharp knife reachable with either hand, and a buddy watching.
Where to go next
Where it matters
Gear this affects
Sources and evidence
- BSAC diving safety guidance and annual incident report — British Sub-Aqua Club (Water-safety or diver-training authority)Relied on for: Diving safety guidance on entanglement and emergency equipment.States this directlyCitation checked — the work exists and is described correctly
Why the 4 connections on this page are here, and the sources
Where it matters
Official guidance — 2 connections
Stated by a fisheries authority, scientific institute or recognised angling body. Authoritative, but summarising rather than demonstrating.
Hole hunting
The technique that most reliably produces it.
- BSAC diving safety guidance and annual incident report — British Sub-Aqua Club (Water-safety or diver-training authority)Relied on for: Diving safety guidance on entanglement hazards, line management and emergency cutting equipment.States this directlyCitation checked — the work exists and is described correctly
Spearfishing
A membership assertion rather than a topical one: this page teaches the discipline or its equipment, so the discipline's mandatory safety posture applies to it.
- CMAS technical and sporting standards for underwater activities — Confédération Mondiale des Activités Subaquatiques (Standards body)Relied on for: Breath-hold spearfishing as a defined discipline with its own technical, equipment and safety standards, set out by the international underwater federation.States this directlyCitation checked — the work exists and is described correctly
- DAN guidance on freediving safety, hypoxia and shallow-water blackout — Divers Alert Network (Water-safety or diver-training authority)Relied on for: That the safety requirements of breath-hold diving apply across the discipline rather than to particular equipment or techniques within it.States this directlyPassage read and verified
Gear this affects
Official guidance — 2 connections
Stated by a fisheries authority, scientific institute or recognised angling body. Authoritative, but summarising rather than demonstrating.
Dive floats and float lines
The equipment that causes the problem it also solves.
- BSAC diving safety guidance and annual incident report — British Sub-Aqua Club (Water-safety or diver-training authority)Relied on for: Diving safety guidance on entanglement hazards, line management and emergency cutting equipment.States this directlyCitation checked — the work exists and is described correctly
Speargun reels
The architecture most associated with the hazard.
- BSAC diving safety guidance and annual incident report — British Sub-Aqua Club (Water-safety or diver-training authority)Relied on for: Diving safety guidance on entanglement hazards, line management and emergency cutting equipment.States this directlyCitation checked — the work exists and is described correctly
What experienced anglers do — 1 connection
Widely and independently recommended by experienced anglers and specialist sources. This is real angling knowledge, not proof: controlled evidence for it is limited, and FishingHQ records it as convention rather than as a demonstrated effect.
Dive floats and float lines
An explainer carrying a mechanism the equipment record depends on.
- CMAS technical and sporting standards for underwater activities — Confédération Mondiale des Activités Subaquatiques (Standards body)Relied on for: Breath-hold spearfishing practice, equipment convention and the safety expectations set out by the international underwater federation.States this directlyCitation checked — the work exists and is described correctly
- BlueWater Hunting and Freediving — BlueWater Freedivers, Ventura, California, 1995 (Practitioner report)Relied on for: Spearfishing equipment and practice: gun, shaft, tip and rigging choice, and the handling of a shot fish, from a practitioner tradition distinct from the European one.States this directlyCitation checked — the work exists and is described correctly
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