Based on information from DAN South Africa and DAN Europe
You've just finished your first dive of the day and everything is going great! You pinch your nose and blow to equalise your ears, but nothing happens. You try again with the same result.
Your ears start to hurt . . . you try again but it's the same!
So what now?
Ascend and end the dive or push on?
No, its time to learn to equalise the correct way . . .
Thats right, you may be equalizing the wrong way!
The real isssue is the way most of us were taught to equalise, and the method that usually works is the wrong way to do it.
It's the Valsalve Maneuver: Pinch your nostrils and blow through your nose. The resulting overpressure in your throat usually forces air up your Eustachian tubes.
How come it works if it's the wrong way?
It works perfectly fine as long as you keep the tubes open ahead of the pressure changes. However, if you do not equalize early or often enough, the pressure differential can force the soft tissues together, closing the ends of the tubes. Forcing air against these soft tissues just locks then shut.
There are three problems . . .
|It does not activate muscles which open the Eustachian tubes. so it may not work if the tubes are alreay locked by a pressure differential.|
|It's all too easy to blow hard enough to damage something.|
|And 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 5 seconds.|
Five Better Ways to Equalize
When to Equalize?
Sooner, and more often than you might think. Most recommend equalizing every metre of descent, but thats often too late. The rule of thumb is to equalize while you are still on the surface before you begin your descent, then equalize on your descent BEFORE you feel and pressure. Many divers descent at a fast rate and will be equalizing almost continuously. The good news is that the deeper you are the less you will need to equalize.
10 Tips to make it easier
- Listen for the "pop"
Before you even get into your dive gear, make sure that when you swallow you hear a "pop" or a "click" in both ears. This indicates that your Eustacean tubes are open.
- Start Early
Several hours before your dive gently equalize your ears. "This has great value and is said to help reduce the chances of a block early on descent", says Dr Earnest S. Campbell, webmaster of Diving Medicine Online.
- Equalize at the Surface
Pre-pressurizing at the surface helps you get past the initial pressure difference as you start to descent where you're often busy dumping air and clearing your mask. It may also inflate your Eustacean tubes so they are slightly bigger. The guide here is to pre-pressurize only if it seems to help you and to pressurize gently.
- Descent Feet First
Air tends to ride up your Eustacean tubes, and fluid like mucus tends to drain downwards. Study has shown that the Valsalva maneuver requires 50% more force when you're in a head down position than head up.
- Look Up
Extending your neck tends to open your Eustacean tubes.
- Stay Ahead
Equalize often, trying to maintain a slight positive pressure in your middle ear.
- Use a Descent Line
Pulling yourself down an anchor or descent line helps control your descent rate more accurately. Without a point of reference your descent rate will probably increase more than you realise. A line also helps you stop your descent quickly if you feel pressure, before Barotrauma has a chance to occur.
- Stop if it Hurts
Don't try to push through pain. Your Eustacean tubes are probably locked shut by pressure differential and the only result will be barotrauma. If your ears begin to hurt, ascent a metre or so and try to equalize again.
- Avoid Tobacco and Alcohol
Both tobacco smoke and alcohol irritate your mucus memranes, promoting more mucus that can block your Eustacean tubes.
- Keep your mask clear
Water up your nose can irritate your mucus membranes, which then produce more of the stuff that clogs.