may be considered an application of professional diving where the diver engages in underwater work for industrial, construction, engineering, maintenance or other commercial purposes. In most jurisdictions, the diving training and certification is the same for all branches of commercial diving, but specialist training may be needed for specific work skills associated with the application. Diver tr
aining is the set of processes through which a person learns the necessary and desirable skills to safely dive underwater within the scope of the diver training standard relevant to the specific training programme. Most diver training follows procedures and schedules laid down in the associated training standard, in a formal training programme, and includes relevant foundational knowledge of the underlying theory, including some basic physics, physiology and environmental information, practical skills training in the selection and safe use of the associated equipment in the specified underwater environment, and assessment of the required skills and knowledge deemed necessary by the certification agency to allow the newly certified diver to dive within the specified range of conditions at an acceptable level of risk. Diver training is closely associated with diver certification or registration, the process of application for and issue of formal recognition of competence by a certification agency or registration authority. Commercial diver certification is generally in terms of a diver training standard published by a national government organisation or department, or an international organisation of which such national bodies are members. Training standards specify the mode of diving, equipment and scope of operations for divers registered in terms of that standard. International recognition of professional diver certification may require registration through a national government agency or an agency appointed by a national government for this purpose. Work skills specific to the underwater environment may be included in diver trailing programmes, but are also often provided independently, either as job training for a specific operation or as generic training by specialists in the fields.