Some evolutionists believe that we came from the sea. If so, returning to it has often been painful, thanks to a few human design flaws.
For example, our ears might not get the CE stamp of approval. Pressure-changes, whether flying or diving, can hurt and cause injury, and our ears are also prone to infections from colds and other illnesses.
As a child, I often played in local seawater swimming pools. The Mediterranean summer sun would evaporate the water, while the kids would dilute it, leaving a foetid mix of concentrated salt and stagnant boy brine in which to swim. The result was countless outer-ear infections.
Surface swimmers often use ear-plugs to seal their vulnerable outer ear canals from the water and whatever contaminants infest it, but divers are told not to. Blocking creates an air-space in the outer ear that can’t be equalised on descent.
This imbalance in pressure – which is higher in your body tissues, which assume the surrounding water pressure, and lower in your sealed-off ear canals – causes the canal walls to swell with body fluid to try to fill in the gap.
At the same time, your eardrum is forced outwards into the canal by back pressure, which can rupture it.
This is called a reverse squeeze, and happened to me after I forgot to flood a tight wetsuit hood, something I was stupid enough to do only after
I got my second instructor rating. It sealed my ear just like an ear-plug.
Warning beginners never to use ear-plugs while diving is right up there with “don’t hold your breath”.
So at 40m, where the pressure is five times that on the surface, why didn’t the ear-plugs
I was wearing recently punch out my eardrums, meet in the middle of my head and turn my brain even mushier? And why was I even diving with them?
Well, I still go into pools from time to time. They are a lot more hygienic now but, even so, I often struggle to shake the water out of my ears and get my hearing back, much more than I do after being in the sea.
I blame this on some of the chemicals used in pools, especially those meant to bond with surface scum and sink it to the bottom, where it’s easier to filter. It seems to congeal in my ears.
And, when I get to dive in the tropics, I’m very conscious of the risk of infections from local water-borne organisms. So when I saw that Surfears was claiming that its earplugs were being used not only by surfers but by freedivers, I asked to try them.