ordinary member of the public, and therefore there is no obligation to train recreational divers in first aid or other medical skills. Nevertheless, first aid training is recommended by most, if not all, recreational diver training agencies. Recreational diving instructors and divemasters, on the other hand, are to a greater or lesser extent responsible for the safety of divers under their guidance, and therefore are generally required to be trained and certified to some level of rescue and first aid competence, as defined in the relevant training standards of the certifying body. In many cases this includes certification in cardiopulmonary resuscitation and first aid oxygen administration for diving accidents. Professional divers Professional divers usually operate as members of a team with a duty of care for other members of the team. Divers are expected to act as standby divers for other members of the team and the duties of a standby diver include rescue attempts if the working diver gets into difficulties. Consequently, professional divers are generally required to be trained in rescue procedures appropriate to the modes of diving they are certified in, and to administer first aid in emergencies. The specific training, competence and registration for these skills varies, and may be specified by state or national legislation or by industry codes of practice. Diving supervisors have a similar duty of care, and as they are responsible for operational planning and safety, generally are also expected to manage emergency procedures, including the first aid that may be required. The level of first aid training, competence and certification will generally take this into account. In South Africa, registered commercial and scientific divers must hold current certification in first aid at the national Level 1, with additional training in oxygen administration for diving accidents, and registered diving supervisors must hold Level 2 first aid certification. Offshore diving contractors frequently follow the IMCA recommendations. Diver medic A diver medic or diving medical technician is a member of a dive team who is trained in advanced first aid. A diver medic recognised by IMCA must be capable of administering first aid and emergency treatment, and carrying out the directions of a physician, and be familiar with diving procedures and compression chamber operation. The diver medic must also be able to assist the diving supervisor with decompression procedures, and provide treatment in a hyperbaric chamber in an emergency. The diver medic must hold,