This table shows the ranks and insignia of officers and warrant officers in the navies of member countries of NATO. NATO maintains a "standard rank scale" in an attempt to match every member country's military rank to corresponding ranks used by the other members. The rank categories were established in the document STANAG 2116, formally titled NATO Codes for Grades of Military Personnel.
Warrant officers (WO1–5)
Warrant officers rank below officers and above enlisted servicemen.
WO are used for United States warrant officers only. Countries not listed use only regular officer ranks, do not have warrant officers, or warrant officers are considered OR (Other/Enlisted Rank).
References
Ranks and insignia of NATO navies' officers Wikipedia(Text) CC BY-SA