Home NI629 Certification of offshore access systems This Guidance Note provides guidelines for the certification of offshore access systems (OAS), based on gangways, and used for the transfer of persons from ships to offshore facilities or from ship to ship. ReferenceTitleDateNI629 R00Certification of offshore access systemsMay 2016check related documents:NR445 Rules for the classification of offshore unitsNR467 Rules for the classification of steel shipsCheck other Bureau Veritas rules and guidelines.