Appendix - Methodology for Assessing Operational Capabilities and Limitations in Ice: Polar Operational Limit Assessment Risk Indexing System (POLARIS)

Introduction

I The Polar Operational Limit Assessment Risk Indexing System (POLARIS) has been developed incorporating experience and best practices from Canada's Arctic Ice Regime Shipping System, the Russian Ice Certificate supplemented by pilot ice assistance as prescribed in the Rules of Navigation on the water area of the Northern Sea Route and other methodologies.

II The basis of POLARIS is an evaluation of the risks posed to the ship by ice conditions in relation to the ship's assigned ice class. It uses the WMO nomenclature and the ice class consistent with the ice class(es) referenced in the Polar Ship Certificate.

III POLARIS uses a Risk Index of Risk Values (RIVs) which are assigned to a ship based on the ice class. The RIVs may be used to evaluate the limitations of the ship operating in an ice regime using input either from historic or current ice charts for voyage planning or in real time from the bridge of the ship.

IV The principal features of POLARIS are:

• .1 the use of a combination of IACS Polar Class ice classes and ice classes assigned equivalence to Finnish-Swedish Ice Class Rules under HELCOM^footnote, which are consistent with ice class references used elsewhere in the Code;

• .2 the use of ice type definitions generally consistent with WMO nomenclature and which can be found on international ice charts;

• .3 consideration of different ice regimes (e.g. waters with partial ice concentrations of different ice types and development stages and ice free waters);

• .4 consideration of ice decay – the outcome of which is a reduced risk due to a reduction in ice strength for some ice types when operating in warmer ambient temperatures; and

• .5 an acknowledgement that ships operating under icebreaker escort have a different risk profile to ships operating independently.

1 Polar Operational Limit Assessment Risk Indexing System (POLARIS)

1.1 Risk Index Values

1.1.1 Ships assigned an ice class and ships without an ice class have been assigned a Risk Index in POLARIS. The Risk Index Values (RIVs) within the Risk Index are values corresponding to a relative risk evaluation for corresponding ice types.

1.1.2 Ice types in POLARIS generally conform to WMO nomenclature used on ice charts with the exception that Medium First Year Ice and Multi Year Ice are given two RIVs. Where the operator can confidently determine that the Medium First Year Ice in a regime is less than 1 metre in thickness, the RIVs in the column "Medium First Year Ice less than 1 m thick" may be used. Otherwise the RIVs in the column "Medium First Year Ice" should be used. Similarly, where the operator can confidently determine that the Multi-Year Ice in a regime is less than 2.5 metres in thickness, the RIVs in the column "Light Multi-Year Ice" may be used. Otherwise the RIVs in the column "Heavy Multi-Year Ice" should be used.

1.1.3 Risk Index values have been developed in tables 1.3 and 1.4. Table 1.4 reflects a reduction in risk associated with decayed ice during times of higher ambient temperatures for certain ice types. The standard Risk Index Values of table 1.3 should be used unless ice decay is confirmed by ice information/visual observation by personnel on board qualified in accordance with chapter 12 of the Polar Code. Only then may table 1.4 be used.

1.2 Risk Index Outcome

1.2.1 POLARIS uses a Risk Index Outcome (RIO) value to assess limitations for operation in ice. Risk Index Values (RIVs) are assigned to the ship based on ice class and ice types present according to tables 1.3 and 1.4. For each ice regime encountered, the Risk Index Values are used to determine a RIO that forms the basis of the decision to operate or the limitation of operations.

1.2.2 The RIO is determined by a summation of the RIVs for each ice type present in the ice regime multiplied by its concentration (expressed in tenths):

• RIO = (C₁xRIV₁)+(C₂xRIV₂)+(C₃xRIV₃)+…(C_nxRIV_n)

• Where C₁…C_n are the concentrations (in tenths) of ice types within the ice regime; and

  • RIV₁…RIV_n are the corresponding Risk Index Values for each ice type.

1.3 Evaluation of the Risk Index Outcome for independent operations

1.3.1 Operational limitations for ships operating independently are determined based on the criteria in table 1.1, using the calculated value of the RIO for the ice regime encountered by the ship, given that due caution of the Mariner will be exercised, taking into account such factors as changes in weather and visibility.

1.3.2 POLARIS addresses three levels of operation, normal operation, elevated operational risk and operation subject to special consideration. For the purpose of POLARIS the RIO values in table 1.1 equal these three levels of operation.

^* See section 1.4

^** See section 1.5

1.4 Elevated Operational Risk

1.4.1 Ships operating in an elevated risk ice regime, based on the RIO outcome, should limit the speed to the values indicated in table 1.2. Operational measures may also include, provision of additional watch keeping or use of icebreaker support. When the speed reduction may impair the ship manoeuvrability, the operation should be avoided.

1.4.2 Ships equipped with ice load measurement and monitoring systems can utilize these systems to calibrate recommended speeds included in table 1.2.

1.4.3 Ships having undergone full scale ice trials and/or calculation-based methodologies can utilize these results to calibrate recommended speeds included in table 1.2.

1.4.4 Recommended speed limits for elevated operational risk conditions should be included in the Polar Water Operational Manual (PWOM).

1.4.5 For voyage planning generally, areas in which the potential to encounter elevated risk operations has been identified should be avoided. Where elevated risk operations are identified and included in a voyage plan, contingency plans should be in place and documented in the PWOM.

1.5 Operations Subject to Special Consideration

1.5.1 Operations Subject to Special Consideration mean operations whereby extreme caution should be exercised by the Master and officers in charge of a navigational watch when navigating in ice.

1.5.2 Where a ship encounters an ice regime where the RIO identifies Operations Subject to Special Consideration, suitable procedures should be contained in the PWOM and should be followed. Such procedures should contain guidance to the operator on reducing the increased risks present to the ship and should include course alteration/re-routing, further reduction in speed and other special measures.

1.5.3 For voyage planning purposes, ice regimes where the RIO identifies Operations Subject to Special Consideration should be avoided.

1.6 Risk Index Outcome for ships under icebreaker escort

1.6.1 In determining the RIO for a ship under icebreaker escort, the ice immediately ahead of the ship should be considered as its ice regime. This regime should include both the track of the icebreaker and, when the icebreaker has a smaller beam than the escorted ship, any unmodified ice out to the maximum beam of the escorted ship.

1.6.2. The icebreaker itself should calculate its own RIO along the intended route.

1.6.3 In general, escorted operations should be reconsidered if the icebreaker encounters a RIO below 0 or if the escorted ship is in an ice regime for which operation is subject to special consideration.

1.6.4 For voyage planning purposes when icebreaker escort is intended to be used, the RIO derived from non-escorted historical ice data may be assumed to be modified by adding 10 to its calculated value. However, it is cautioned that this is an average value which can vary significantly. For actual operations, the RIO under escort should not be modified and should be derived as described in the previous paragraphs.

1.7 Operations in ice regimes containing glacial ice

1.7.1 The presence of glacial ice represents additional risks to the ship. Areas containing glacial ice should be approached with caution.

1.7.2 Appropriate training should be provided to the Master and officers in charge of a navigational watch when navigating in ice on identification and avoidance of glacial ice and the consequences of collision. Measures to avoid glacial ice should be documented in the PWOM.

1.7.3 Where glacial ice is encountered, in addition to the RIO, a safe stand-off distance should be observed by the ship. This stand-off distance should be recorded in the PWOM.