Equalizing the ears is one of the most basic skills a diver should master before taking that first dive. Failure to equalize could result in lasting damage. Scuba divers are vulnerable to ear problems because the delicate mechanisms that govern our hearing and balance just aren’t designed for the rapid pressure changes that result from diving.
The key to safe equalizing is opening the normally closed Eustachian tubes. Each has a kind of one way valve at its lower end called the “Eustachian cushion,” which prevents contaminants in your nose from migrating up to your middle ears. Opening the tubes, to allow higher-pressure air from your throat to enter your middle ears, normally requires a conscious act. Swallowing usually does it too.
There are different techniques or methods to equalize the ear but the most commonly taught and practiced method is called the Valsalva Manuever (Pinch Your Nose and Blow).
Pinch your nostrils (or close them against your mask skirt) and blow through your nose. The resulting overpressure in your throat usually forces air up your Eustachian tubes.
But the Valsalva maneuver has three problems:
1. It does not activate muscles which open the Eustachian tubes, so it may not work if the tubes are already locked by a pressure differential.
2. It’s too easy to blow hard enough to damage something.
3. Blowing against a blocked nose raises your internal fluid pressure, including the fluid pressure in your inner ear, which may rupture your “round windows.” So don’t blow too hard, and don’t maintain pressure for more than five seconds.
Other methods require patience and a lot of practice, but they could prove as effective alternatives to the Valsalva manuever.
The Frenzel Maneuver
Pinch Your Nose and Make the Sound of the Letter “K”
Close your nostrils, and close the back of your throat as if straining to lift a weight. Then make the sound of the letter “K.” This forces the back of your tongue upward, compressing air against the openings of your Eustachian tubes.
Pinch Your Nose and Swallow
With your nostrils pinched or blocked against your mask skirt, swallow. Swallowing pulls open your Eustachian tubes while the movement of your tongue, with your nose closed, compresses air against them.
Voluntary Tubal Opening
Tense Your Throat and Push Your Jaw Forward
Tense the muscles of the soft palate and the throat while pushing the jaw forward and down as if starting to yawn. These muscles pull the Eustachian tubes open. This requires a lot of practice, but some divers can learn to control those muscles and hold their tubes open for continuous equalization.
Swallowing—and various methods of equalizing—are all ways of opening the normally closed Eustachian tubes, reducing the pressure differential between the outer ear and inner ear. The safest clearing methods utilize the muscles of the throat to open the tubes. Unfortunately, the Valsalva maneuver that most divers are taught does not activate these muscles, but forces air from the throat into the Eustachian tubes.