sentences:  The qualification required to dive at work in South Africa is linked to the mode of diving, the equipment to be used, and the diving environment.There are six classes of occupational diver registration, all of which may be employed in scientific diving operations within the scope of the specified competence and when supported by the required infrastructure.In each of these classes, the fundamental diving or supervisory competences include those of the class with the next higher number, though specialist skills may differ from person to person and may have no obvious connection to the registered class.