DIVER SAFETY & MEDICAL GUIDELINES

Equalizing early and continuously prevents middle ear barotrauma.

The Science: Eustachian Tubes & Water Pressure

Your eardrum separates your outer ear canal from the air-filled space of your middle ear. As you descend, surrounding water pressure increases rapidly, pushing the eardrum inward. The Eustachian tubes—which connect the back of your throat to your middle ear spaces—are naturally closed. To equalize, muscle action or air pressure must open these tubes to allow high-pressure air into the middle ear, balancing the pressure across the eardrum.

Ear Equalization Methods

1. Start Equalizing BEFORE You Submerge

Listen for a gentle "pop" or "click" in both ears while on the boat or surface buoy before deflating your BCD. Pre-opening your Eustachian tubes ensures they are clear and ready before water pressure begins clamping them shut.

2. Equalize Continuously in the First 15 Feet (5 Meters)

Pressure changes are relative and most severe near the surface:

• Do NOT wait for a schedule or pain: Equalize continuously with every breath during your first 10–15 feet of descent.
• Stay ahead of the pressure: If you feel fullness or discomfort, you have already waited too long.

3. Descend Feet-First

Studies published by DAN show that equalizing requires up to 150% more effort when in a head-down orientation. Descending feet-first allows air to rise more naturally up the Eustachian tubes toward your middle ear.

4. Choose the Right Equalization Technique

While the gentle Valsalva maneuver (pinching your nose and blowing gently) is standard, it doesn't open the Eustachian tube muscles directly. Consider learning these alternative techniques recommended by DAN:

• Lowry Technique: Pinch your nose, blow gently, AND swallow at the same time.
• Frenzel Maneuver: Pinch your nose and push the back of your tongue upward against the roof of your mouth to drive air upward without using diaphragm force.
• Marcante-Odaglia / VTO: Contract the soft palate muscles while flexing your jaw to pull the Eustachian tubes open directly.

5. Never Force It: The "Stop, Ascend, Equalize" Rule

Never forcefully blow against blocked ears! Excessive force during a Valsalva maneuver can rupture the delicate round or oval windows of the inner ear, causing permanent hearing loss or severe vertigo. If your ear locks: Stop your descent immediately, signal your buddy, ascend 2–3 feet until the discomfort completely disappears, equalize gently, and then resume your descent slowly.

Official DAN Safety Resource

For a comprehensive, illustrated breakdown of ear anatomy, equalization maneuvers, and barotrauma prevention, download the official guide courtesy of Divers Alert Network (DAN):

Download DAN's "Beat the Squeeze" Smart Guide (PDF)

Credit & Special Thanks: Divers Alert Network (DAN) — Medical & Safety Services.

Medical Safety Note: Decongestants & Cold Diving

Never dive with congestion, allergies, or a cold. Using oral or spray decongestants to force a dive risks a dangerous reverse block—where medication wears off mid-dive, trapping expanding air inside your middle ear or sinuses during ascent.

Remember DAN’s rule: It is always better to cancel one dive than to risk permanent ear damage that ends your diving career forever.