5. Take care of your teeth

One thing I certainly learned in my first decompression session was how important it was for my teeth to be in good shape.

After a couple of hours of being in the chamber, one of my fillings blew off. Thankfully for me, when it blew off there was no pain, just a hole left where the filling used to sit. Other's aren't so lucky. I've seen one guy have a crown blow off, taking part of the tooth and gum with it. Painful stuff to have to endure for the next three days

If a tooth is decayed below the filling and air is locked into that space, during decompression it will blow off. Be a regular at the dentist is the advice here.

6. Sharks are no less scary after 30 years

When you’re young, brave and learning to be a deep sea diver, you fear nothing. Working in the North Sea and talking to the cod, skate and lobsters is fun, but nobody tells you that when you see your first shark, you are going to crap your pants – no matter how brave you are.

Sharks are scary, even the little ones. If they like you, they won’t eat you, but they have a way of always making you feel nervy. They look at you like a meal. You've got nowhere to hide and feel very vulnerable.