Part B - Verifications and approval requirements 
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4.1.1 Technical codes of practice 
The following primary codes of practice for the verification of offshore wind turbines shall ap 
ply: 
DIN EN 61400-22 Wind turbines - part 22: Conformity testing and certification, German 
version EN 61400-22:2011 
DIN EN 61400-3 Wind turbines - Part 3: Design requirements for offshore wind tur 
bines 
GL-IV-2 GL Rules and Guidelines, IV Industrial Services, Part 2 Guideline for 
the Certification of Offshore Wind Turbines 
In the following, a type certification based on the codes of practice listed above shall be 
termed an “offshore type certification”. 
Codes of practice for the verification of onshore wind turbines are not sufficient as these do 
not cover marine conditions. An existing “onshore type certification” may be extended under 
application of the above offshore codes of practice in consultation with the appointed inspec 
tor. 
4.2 Development phase 
4.2.1 Preliminary remarks 
Generally, the decision to implement a specific offshore wind turbine type is not yet made dur 
ing the development phase. However, in order to be able to assess the technical feasibility of 
the project and compile the preliminary design of the foundation concepts, minimum basic 
technical parameters for the rotor/nacelle assembly are required. These parameters shall be 
provided as a range of parameters, or as maximum values, so as to be able to include differ 
ent installation types in the considerations. 
4.2.2 Requirements and required verifications 
The following basic parameters describing the offshore wind turbine shall be submitted during 
the development phase: 
• Rotor diameter 
• Hub height (above the mean sea level) 
• Rated output 
• Installation type (axial direction, output control, number of rotor blades, windward or lee 
ward runner): Should the planned installation type deviate from the current state of the art 
(horizontal rotation axis, variable rotational speeds, adjustable blade pitch, windward run 
ner), a more exact description of the planned installation shall be submitted at this point 
which shall include a complete technical specification sheet. 
• Number of installations and wind farm configuration (erection plan and respective installa 
tion types) 
These basic parameters shall be submitted as “from-to” figures or maximum values. As a re 
sult, the decision to implement a specific type of installation is not required during the devel 
opment phase. With regard to the preliminary design of the foundation concepts, it may be 
necessary to supply preliminary loading assumptions for the rotor/nacelle assembly.