Diving certification for beginner through to instructor levels is issued by prominent worldwide organisations such as PADI, which rely largely on self-regulation.
About 70 per cent of divers in Hong Kong have received their diving certificates through the PADI system.
According to the system, people select a training course that has been certified by PADI - the Professional Association of Diving Instructors - and which is conducted by a recognised instructor.
Learners, no matter where they do the training, use the same study modules, which are designed by the diving organisation.
PADI has a very clear requirement on course contents. For example, a beginner course requires six to 10 hours of theory study, six to eight hours of practice in confined water, such as a swimming pool, and then four to six to dives in open water. A written examination and skill assessment may be conducted, at the discretion of the instructor. However, PADI does not carry out checks on the implementation of the training course unless a student files a complaint to the organisation.
Once the instructor believes a student has the skills to fulfil the course requirements, the instructor issues the learner a certificate.
Students can go on to get certificates for advanced diving, rescue diving and instruction. No re-examination or refresher course is required for instructors; they can teach diving even if they have not been diving for a long time.
In the last several years, criticism has arisen that the international training organisations make diving training courses too short and easy, and that they 'profit' from the growing demand for diving training.
Dive centres, resorts, educational facilities and divemasters teach the bulk of the world's recreational divers, with most of the instructors running the training as a business.