The Zone/Date System

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2.1 Why Introduce an Ice Regime System?

Since the introduction of the Arctic Shipping Pollution Prevention Regulations, ships of different class or type have their access to the Arctic governed by the Zone / Date System. The Arctic is divided into 16 zones, where Zone 1 is generally considered to have the most demanding conditions, and Zone 16 the least.

Access to each zone was established, based on historical data related to the probable ice conditions at different times of the year. The least capable ships would never be permitted access to the most stringent zones, while the most capable would never be denied access. For other combinations of ship and zone, allowable operating windows were defined; hence the system is often referred to as the Zone / Date System. Both the access dates and the zones for 'Arctic Class' ships and 'Type' ship classes are clearly shown together on the following pages.

Although simple and predictable, this system has one major drawback - ice conditions vary significantly from year to year. So in a severe year, an inexperienced operator might attempt a voyage well beyond the capabilities of the ship. In a light ice year, the rigidity of the regulatory system may prevent ships from transiting areas which could be completely free of ice. The Arctic Ice Regime Shipping System ( AIRSS ) developed through the joint work of government and industry, is a more flexible and safe system.

2.2 Using the Zone / Date Table - Arctic Class vs CAC Vessels

As mentioned earlier, the AIRSS has been introduced through a transitional period, during which it can be used to extend the operating areas/seasons when ice conditions permit outside of the Zone / Date System. Ships may however continue to use the Dates of Entry Table for basic passage planning to learn when the lighter ice conditions may occur. The Ice Regime System is to be used when making access decisions outside of the established dates.

Since the Zone / Date Table only uses the existing Arctic Class and Type designations, owners of CAC ships are prompted to use the Ice Regime System outside of the normal Zone / Date System. CAC ships could, if they choose, also use the Table 1 of the Equivalent Standards For The Construction Of Arctic Class Ships, TP 12260 to find their equivalent Arctic Class which would allow them to use the Zone / Date System. Arctic Class ships however, do not have a choice because the table is not reciprocal. Thus those shipowners are encouraged to apply for a CAC equivalency to allow them to utilize the Ice Regime System.

Following the transitional period, it is proposed that the AIRSS could completely replace the Zone / Date System, but this will only be done through the consultation process. User feedback during the transition period coupled with operational experience will allow fine-tuning of the system. All operators are strongly encouraged to provide comments and their suggestions for improvements, as outlined at the beginning of this publication.

Note: There are additional date restrictions contained in Section 6. of the Arctic Shipping Pollution Prevention Regulations for certain ships.

June, 1996

2.3 Structural Requirements

A new system now exists for determining how the most highly ice-strengthened vessels are classed by Transport Canada, Marine Safety. Four Canadian Arctic Categories ( CAC ) have now replaced the previous Arctic 1 - Arctic 10 Classes. Details of the new structural classifications are provided in the Transport Canada publication Equivalent Standards For The Construction Of Arctic Class Ships - TP 12260 (see Section 8.2); to summarize:

• CAC 1 is seen as an icebreaker which can operate anywhere in the Arctic and can proceed through Multi-Year ice continuously or by ramming according to the owner's performance requirements. A CAC 1 ship is capable of navigation in any ice regime found in the Canadian Arctic and unrestricted ramming of the heaviest ice features (except icebergs or similar ice formations) for the purpose of ice management.
• Class CAC 2 is seen as a commercial cargo carrying ship which can trade anywhere in the Arctic, but would take the easiest route. It could proceed through Multi-Year ice continuously or by ramming according to the owner's performance requirements. A CAC 2 ship is capable of navigation in any ice regime found in the Canadian Arctic and ramming of heavy ice feature restricted by its structural capability.
• Class CAC 3 is seen as commercial cargo carrying ship which can trade in the Arctic where ice regimes permit. It would proceed through Multi-Year ice only when it is unavoidable and would do so in a controlled manner usually by ramming. It would be unrestricted in Second and heavy First-Year ice.
• Class CAC 4 is seen as commercial cargo carrying ship which can trade in the Arctic where ice regimes permit. It would be capable of navigating in any thickness of First-Year ice found in the Canadian Arctic, including First-Year ridges. It would avoid Multi-Year ice and when this is not possible it would push or ram at very low speeds.

Vessels CAC 1, 2, 3, and 4 may also be considered suitable escorts, capable of escorting ships of lower classes.

Canada has developed structural standards for each of these classes. Ships built to polar standards of other Classification Societies and national authorities can apply for CAC equivalency on a case-by-case basis, as can owners of vessels previously classified under the existing Canadian system for Arctic Class vessels.

The approach that Canada took was to base: Type A, B, C, D, and E vessels on the Finnish- Swedish (Baltic) rules where ‘Type A ships can operate in Thick First-Year ice and Type E ships are considered Open Water vessels with no ice strengthening. The Type designation will apply to most of ships working in the Arctic which are less structurally capable than CAC vessels, but have some level of ice strengthening over and above open water requirements.

The ‘Type’ ships have the capacity to work in First-Year ice of approximately the thicknesses and types shown below:

ASPPR Type Ships and their Approximate WMO Ice Conditions

2.4 Vessel Certification - Arctic Pollution Prevention Certificates

Ships that sail into Canada's Shipping Safety Control Zones with a valid Arctic Pollution Prevention Certificate comply with the Arctic Shipping Pollution Prevention Regulations. Vessels without the certificate, which is not mandatory, may be inspected for compliance. Thus all vessels are encouraged to have a valid Arctic Certificate issued prior to undertaking any voyage into the Shipping Safety Control Zones. The certificate may also be issued outside Canada by an approved Classification Society or within Canada waters by the Administration.

The Arctic Pollution Prevention Certificate indicates what the ice class of the vessel is at specific drafts. The ship's ice class (Type, Arctic Class or CAC ) designation could now either be applied to the Zone / Date Table previous pages) or directly in the case of a CAC ship to the Arctic Ice Regime Shipping System using the Table of Ice Multipliers (page 11). Mariners intending to navigate in ice-covered waters should ensure they know the ice class or type of their ship, and have a good understanding of the combinations of ice conditions and operating procedures which are likely to be safe for the voyage.

Note: The specific details related to the Arctic Pollution Prevention Certificate can be found in Sections 12. to 18. of the Arctic Shipping Pollution Prevention Regulations.

2.5 Coast Guard Icebreakers and the AIRSS

Canadian Coast Guard ( CCG ) icebreakers like many other vessels have been built to a variety of structural standards. Government icebreakers are not classed under the Zone / Date System for operational purposes. In order to provide feedback, CCG ice-capable vessels are encouraged to perform Ice Numeral calculations and for this purpose structural equivalency may be determined. Arctic Pollution Prevention Certificates will not be issued to CCG ice-capable vessels as per current policy.

Icebreakers that are involved with an escort are however encouraged to utilize the AIRSS from the perspective of the commercial ship following them while looking at the icebreaker’s track (Section 7.2.1) or for voyage planning.

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