To get started you simply need to be able to swim, understand a few elementary principles of physics, and be able to "pop" your ears (release air pressure in your inner ears by holding your nose and blowing, rather as you would in an aeroplane). The first step is to qualify as an open water diver (cave diving and night diving - when the coral colours look magnificent illuminated by underwater torches - require more advanced instruction). At the end of your course you will need to pass a basic written test and be able to perform a few underwater exercises. Apart from introductory dives, you will not be sold air in scuba tanks unless you can produce internationally recognised certification showing that you have been trained.
Where to train
In Britain there are two options: a BSAC (British Sub-Aqua Club) or a PADI (US-run Professional Association of Dive Instructors) course. BSAC is very much a club: you train and become a member at one of the 1,400 branches. Courses are geared for British diving - in conditions that are generally difficult. Your qualification, though, will be internationally recognised.
PADI training, on the other hand, is designed for easier, international resort diving in warmer countries. You can attend PADI courses in Britain or learn from scratch on a diving holiday abroad.
For more information contact BSAC at Telfords Quay, Ellesmere Port, South Wirral, Cheshire L65 4FY (0151-357 1951) or PADI at Unit 6, Unicorn Park, Whitby Road, Bristol BS4 4EX (0117-971 1717). Details of training courses (which start at around pounds 99) are advertised in magazines such as Diver and Sports Diver.
The underwater environment
A diver generally poses more of a threat to sea life (even sharks) than such life does to him. A group of divers can leave a trail of destruction by crashing about, dropping bits of equipment and teasing the fish. Wherever you train, it will be emphasised that you must learn to protect the environment you are entering - coral reefs, in particular, are extremely fragile. In many countries collecting specimens such as shells and even dead coral is strictly illegal.