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What should you consider when you want to dive 5-7m at snorkeling?
That's very important Make sure the pressure equalization.
The biggest error in pressure equalization is to make it too late. At the first meters and centimeters under the water surface, the pressure increase is strongest. Therefore, the first pressure equalization must be made very early. A good depth graduation would be 2 m, 4 m, 10 m.
Wait too long, e.g. to 3 or 4 m or even until the ears are in pain, it is usually already too late. Then, by the prevailing pressure difference, the ear trumpet (Eustachsche tube) closed so far, that even bubbles in the held nose no longer functionErt.
Experienced divers also get the pressure equalization through dry swallow, which they are usually already at 1m, 3 m 6 m 10 m. But the ear trumpet must be free.
In cold, the ear trumpet is never free but swollen and therefore one must never dive. Whether the ear trumpet is free, you can also check before dipping by still holding your nose in the dryness and lightly pure. You have to feel that directly in the ear or on the eardrums.
No. This is not physically possible. And a longer snorkel, as mentioned here in another response as a possibility, also does not lead to diving disease, but for safe death because of collapsing the lungs. MaximAle snorkel length is 35 centimeters.
No, snorkeling is not a real diving.
Coming on how long your snorkel is.