Editing Dynamic positioning (section)

==International Maritime Organization class requirements==
Based on [[International Maritime Organization|IMO]] (International Maritime Organization) publication 645<ref name="IMO 645" /> the [[Classification Society|Classification Societies]] have issued rules for Dynamic Positioned Ships described as Class 1, Class 2 and Class 3.

*Equipment Class 1 has no redundancy.<br />Loss of position may occur in the event of a single fault.
*Equipment Class 2 has redundancy so that no single fault in an active system will cause the system to fail.<br />Loss of position should not occur from a single fault of an active component or system such as generators, thruster, switchboards, remote controlled valves etc., but may occur after failure of a static component such as cables, pipes, manual valves etc.
*Equipment Class 3 which also has to withstand fire or flood in any one compartment without the system failing.<br />Loss of position should not occur from any single failure including a completely burnt fire subdivision or flooded watertight compartment.

Classification Societies have their own Class notations:

{| class="wikitable"
|- valign="top"
|style="background:#DDDDDD"| Description ||style="background:#DDDDDD"| [[International Maritime Organization|IMO]]<br />Equipment Class||style="background:#DDDDDD"| [[Lloyd's Register|LR]]<br />Equipment Class ||style="background:#DDDDDD"| [[Det Norske Veritas|DNV]]<br />Equipment Class ||style="background:#DDDDDD"| [[Germanischer Lloyd|GL]]<br />Equipment Class||style="background:#DDDDDD"| [[American Bureau of Shipping|ABS]]<br />Equipment Class||style="background:#DDDDDD"| [[Nippon Kaiji Kyokai|NK]]<br />Equipment Class||style="background:#DDDDDD"| [[Bureau Veritas|BV]]<br />Equipment Class
|-
| style="background:#DDDDDD"| Manual position control and automatic heading control under specified maximum environmental conditions || - || DP(CM) || DYNPOS-AUTS || - || DPS-0 || -
|-
|- valign="top"
| style="background:#DDDDDD"| Automatic and manual position and heading control under specified maximum environmental conditions || Class 1 || DP(AM) || DYNPOS-AUT & DPS1|| DP 1 || DPS-1 || DPS A || DYNAPOS AM/AT
|-
|- valign="top"
| style="background:#DDDDDD"| Automatic and manual position and heading control under specified maximum environmental conditions, during and following any single fault excluding loss of a compartment. (Two independent computer systems). || Class 2 || DP(AA) || DYNPOS-AUTR & DPS2 || DP 2 || DPS-2 || DPS B || DYNAPOS AM/AT R
|-
|- valign="top"
| style="background:#DDDDDD"| Automatic and manual position and heading control under specified maximum environmental conditions, during and following any single fault including loss of a compartment due to fire or flood. (At least two independent computer systems with a separate backup system separated by A60 class division). || Class 3 || DP(AAA) || DYNPOS-AUTRO & DPS3 || DP 3 || DPS-3 || DPS C || DYNAPOS AM/AT RS
|}
DNV rules 2011 Pt6 Ch7 introduced "DPS" series of classification to compete with ABS "DPS" series.