We have now finished the first part of our scuba diving course, both in the pool and in the classroom, and tomorrow we head out to the Great Barrier Reef for a couple of days in the open water.

We turned up yesterday morning to the first day of our course along with about twelve others and were taken into the back to what would be our classroom over the next couple of days and after completing a quick medical check (had no idea how hard it is to stand on one leg with your eyes shut??) we were ready to begin.

Our instructor was a Dutch guy called Mike who soon had us watching four hours of videos covering everything from basic dive techniques to health and safety regulations and everything in between, with a test after each one that we needed to complete. After a break for lunch we headed out the back to the pool to complete the swimming requirements, which were no more than swimming 200 metres and treading water for ten minutes, then it was time to get geared up with the necessary equipment before getting into the water proper for the first time.

By the time we had our flippers, masks and snorkels, weights, BCD (the vest that you fill with air to keep you afloat) and air tanks it was far from easy to make our way to the pool, but after much struggling we were all in the water and ready to scuba! Once we were paired off into "buddies" we practiced the hand signals and basic maneuversbefore moving onto some of the required skills such as taking our masks off under water and swapping air with our buddies.

We were in the pool for little over three hours and by the time we had finished our first day we were pretty knackered and ready for an early night, but for the first time in years we had homework and revision to do for the final exam the next day.

Today's learning was started in the pool and we spent most of it in the deeper section so that we could get used to equalizing (so our ears didn't explode) and to complete some of the more difficult exercises, such as taking off our BCD's and tanks underwater. We also had to be able to breathe out consistently for thirty seconds so that if we ever had to do an emergency accent without air we could breathe out for the required time so that we don't drown.

It's pretty dangerous this diving lark! You can only ascend at a maximum speed of eighteen metres in one minute and that's an emergency accent rate, so if you are down lower than that and you run out of air, you need to make sure that your buddy has some air left or your going to want to get to the surface before you run out and if you do that you are likely to get the bends! And if you are stupid enough to hold your breath while you ascend it will cause your lungs to explode and we were reliably informed by our instructor that this is quite likely to hurt a bit. Not only that, but it will be a couple of years before you can breathe again painlessly, about five years before the lungs are strong enough to cope with swimming, seven to eight years for you to be able to take a breath and go a little underwater, and you will never be able to scuba dive again (or dive at all over more than a metre so it also rules out any underwater exploration when snorkelling as well). And these are just a couple of the more obvious problems.

Once we had completed all the practical exercises it was back into the classroom for a few more hours of videos and tests, and then it was onto the final exam that we had to pass before we were allowed out into the open water. It was a little strange doing our first exams in well over two years, but we both passed easily enough and were allowed to leave once we were done.

Tomorrow we are heading out into the reef where we will have to complete all the exercises again to prove we can cope with the extra issues of salt water and the fact that we will be eighteen metres under the water instead of the two metres in the training pool.