There is a way to do 'wet' equalizing techniques more safely (in terms of infections).
You can use sterile saline solution (like for contact lenses), which contains antibacterial agents. You fill your sinuses on the surface and then put a nose clip on.
I came up with a different wet equalizing technique in late 2003 as a method to equalize during FRC dives, beyond the mouthfill depth. Even for me, a perfect mouthfill on an FRC dive gets me to only 70m. So, the idea is to have a cup of saline on the surface. You inhale (last breath), or, in the case of FRC, exhale, then, tilt your head back and pour the saline into your mouth. Then start the dive. You equalize with air, normally, in the first few meters, keeping the water in your mouth. Then, around 20m, you do a partial somersault and open your soft palate, allowing the water to flow from your mouth into your sinuses. Then, you close your soft palate, sealing the water into your sinuses. Then, you tilt your head back, and equalize, but if done properly no water gets into your ears, because the angle of your head prevents it.
This is the most difficult equalizing technique ever invented. Even having mastered the mouthfill, it took me many hours and weeks of practice and still I couldn't do this technique while still relaxed. There is a huge gag reflex which occurs when you allow the water to flow from the mouth to the sinuses---DO NOT ATTEMPT THIS WITHOUT PROPER SAFETY! You could easily DROWN! I first practiced it on land many times, and then had my buddy follow me all the way down to 20m to grab me if I chocked on the water.
The watersuck technique, if mastered, has some advantages:
- Can be done in AIDA rules (with a mask)
- No water in the eutachian tubes
- No chance of infection (sterile saline), even if you screw up
Of course, because you don't get water into your eustachian tubes, the ultimate depth limit of this technique is less than the Pipin technique.
However, with a 192m limit for standard mouthfill, I calculated that the watersuck technique increases your depth limit by about 40%, so about 269m. If you want to go deeper than that, then you can use Pipin's technique.