To ascertain the legal equivalence between ECDIS and paper products the ECDIS systems installed on a ship must be checked and approved by an official body who is duly authorised by IMO and IEC.
Following standards define the requirements:
Certain areas are not fully covered with ENC data. Therefore, it is allowed to carry raster charts (RNC) in RCDS mode together with a reduced portfolio of official paper charts. (Recommendations see under Port State Control).