The Secret Art of Hands-Free Equalisation

What is Hands-Free Equalization?

Every diver knows the problem. You descend, the pressure builds, and you have to stop — pinch your nose, force air into your ears, and then keep going. It breaks your streamline, occupies your hands, and demands constant mental attention. Now imagine descending without any of that. No hands touching your face. No pressure, no forcing. Just you, moving through the water, with your ears equalizing automatically as you go.

That’s hands-free equalization — also known as BTV (béance tubaire volontaire, French for voluntary tube opening) or VTO (voluntary tubal opening). Rather than using pressure to force air through the Eustachian tubes, this technique involves voluntarily activating a small muscle called the Tensor Veli Palatini (TVP), which mechanically opens the Eustachian tubes on demand. No pressure. No pinching. No hands required.

It is the only purely mechanical equalisation technique in freediving. And it is extraordinarily rare.

“If you have the art of stifling a yawn while in polite company, you might have the skill to join the exclusive band of divers who can perfect this technique.”

— Dr. Georges Delonca, French Navy, 1950s

Where Hands-Free Equalisation Sits in the Hierarchy

There are three main equalisation methods used in freediving, each with different mechanics, risk profiles, and depth ceilings.

Beginner — Valsalva

Pinch and blow
Familiar to anyone who’s flown with a cold
Too much pressure and too little control
Not recommended for serious freediving

Intermediate to Advanced — Frenzel / Mouthfill

The industry standard
Uses the tongue as a piston to push trapped air into the middle ear
Mouthfill is the advanced version used when lung volume decreases at depth

Advanced — Rare + Hands-Free (BTV/VTO)

Pure muscle activation
No pressure and no nose pinch
Eustachian tubes open voluntarily through TVP engagement
The gentlest technique on the ears
Works seamlessly with mouthfill at depth

Hands-Free Mouthfill — Going Beyond the Limit

What makes Dan Parsons one of Australia’s deepest hands-free equalizers isn’t just the ability to open his Eustachian tubes — it’s how he applies that ability at serious depth. At around 20–25 metres, as the lungs approach residual volume and it becomes impossible to shift more air from the chest, Dan takes a mouthfill: a large reservoir of air held in the oral cavity.

From that point on, the hands-free technique takes over completely. The TVP muscle activates, the tubes open, and air moves from the mouth into the middle ear in a continuous, pressure-free cycle — all the way to the bottom. No hands on his face. No forcing. Just clean, mechanical equalization, deeper than almost anyone in the country can achieve using the same method.

Where most freedivers doing Frenzel use their tongue as a piston to push air, Dan’s tubes simply open. The air follows. And as the mouthfill compresses with depth, his cheeks and jaw naturally close inward, managing the reducing air volume without conscious effort. It is, by most accounts, the most elegant form of equalization in the sport.

Hands-free is not a backup for when Frenzel gets hard. It is a fundamentally different approach — and in the hands of someone who has mastered it, it is arguably superior.

By the Numbers

Less than 30% of hands-free divers learned it via formal certification
121m deepest known hands-free dive (Andrea Zuccari, with mask)
0 major certification agencies formally teach this technique

What People Get Wrong About Hands-Free

The freediving community is full of misinformation about this technique. Here are the most common myths — and the truth behind each of them.

✗ “You can’t go deeper than 20–30 metres with hands-free.”

False. Andrea Zuccari performed a verified 121-metre hands-free dive with a mask. The only real depth limit is how effectively you can combine the technique with a mouthfill and manage your air at depth. Dan Parsons is proof this works far below 30 metres.

✗ “It’s a genetic gift — you either have it or you don’t.”

False. The TVP muscle that opens your Eustachian tubes is the same one you use every time you swallow, yawn, or chew. Everyone activates it unconsciously. The challenge is learning to do it voluntarily and on demand — a trainable motor skill, not an anatomical lottery.

✗ “Using a nose clip or mouthfill means you’re not really doing hands-free.”

False. A nose clip simply seals the nasal cavity — it doesn’t contribute to equalization at all. And mouthfill is an air management technique, not an equalization technique. Hands-free divers routinely combine all three. The mechanism — TVP activation, no pressure — remains entirely hands-free.

✗ “Hands-free eliminates all barotrauma risk.”

False — and a dangerous misconception. Because the technique doesn’t use pressure, the Eustachian tubes are more vulnerable if equalization is delayed. Equalizing early and often is even more critical than with Frenzel. Once negative pressure builds, the TVP muscle alone cannot overcome it.

✓ “It’s the gentlest technique on the ears.”

True. Because it works purely through mechanical muscle activation rather than forced air pressure, it is considered the least traumatic equalization method for the eardrum and middle ear — one of the key reasons serious deep divers and spearfishers seek to master it..

Why This Technique Changes Everything

For a freediver, equalization is the invisible ceiling. No matter how good your breath-hold, your technique, your relaxation — if your ears stop you, your dive stops with them. Most divers hit this ceiling somewhere between 20 and 40 metres, working through the limitations of Frenzel with progressively complicated mouthfill coordination.

Hands-free removes that ceiling in a different way. It doesn’t fight pressure — it sidesteps it entirely. The tubes open before pressure becomes a problem. There’s no forcing, no tongue mechanics to coordinate under compression, no moment where you realise you’ve left your equalization too late.

For spearfishers and underwater photographers, the advantages are obvious: both hands remain free throughout the dive. You can aim, track, and shoot without breaking your position to pinch your nose. For deep competitive freedivers, it means the mental bandwidth usually spent on equalization can go toward relaxation, hydrodynamics, and awareness of your body at depth.

Guillaume Néry — who descended to 126 metres — uses continuous hands-free equalization throughout his dives, keeping his Eustachian tubes open from the moment he enters the water. His equalization simply happens. That is the promise of hands-free at its highest level.

“I equalize from the beginning to the end of my descent using BTV, meaning I keep my Eustachian tubes continuously open through the activation of small muscles. This technique allows me to focus on relaxation and hydrodynamics.”
— Guillaume Néry, Multiple Freediving World Champion

Why Almost Nobody Teaches It

The frustrating reality is that none of the major freediving certification bodies — not AIDA, SSI, PADI, CMAS, or Molchanov — formally teach hands-free equalization. The knowledge passed informally — peer to peer, forum post to forum post — full of contradictions, half-truths, and flat-out myths.

Less than 30% of hands-free divers surveyed said they learned about the technique during any kind of course. The rest pieced it together on their own.

Students who naturally equalize hands-free often struggle in courses, because their instructors don’t recognise what they’re doing and teach them pressure-based techniques that don’t work for their anatomy. Divers who want to learn it find almost no structured pathway to do so.

Which is exactly why voices like Dan Parsons’ matter. Experienced hands-free divers — particularly those who have pushed the technique to genuine depth — are among the only people in the world who can speak to it with authority.

Can You Actually Learn This?

Yes. But it requires understanding what you’re actually trying to train.

The TVP muscle is not a muscle most people have ever consciously activated. It’s deep, it has almost no proprioceptive feedback, and the sensation of opening your Eustachian tubes voluntarily feels different to almost everyone who discovers it. Some describe it as a subtle jaw movement. Others feel it as a widening at the back of the throat. Many find it on land first — a quiet click or hum — before they can replicate it in the water.

The path typically starts dry: learning to feel the tube opening at surface pressure, building hundreds of repetitions until the muscle engages reliably on demand. Then comes the much harder transition — reproducing that same activation while horizontal in water, under increasing pressure, while managing breath-hold and relaxation simultaneously.

The important caveat: hands-free is not a shortcut past Frenzel. If you can’t equalize at all, this is not where you start. But for divers who have a solid foundation and want to explore what’s possible beyond it — this is one of the most rewarding frontiers in the sport.