BTV — Voluntary Tubal Opening

BTV is a way to open the Eustachian tubes manually. It helps divers equalize their ears when the Valsalva maneuver fails.

You use this during deep descents or when pressure changes are rapid. It affects the middle ear space directly. I often saw divers struggle with this at 15 m in Koh Tao because of sinus congestion. Most people attempt it by swallowing or moving the jaw.

Do not force the movement too hard. A common mistake is applying excessive pressure against a blocked tube. This can cause ear pain or even a burst eardrum. Try gentle jaw movements instead. Keep your descent slow so your body has time to adjust.