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arctic classes

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The ABS database contains hundreds of ships classed with an Arctic Ice class. This information should be public domain. It is, however, not. The information is only available to ship owners, shipyards, and ABS engineers. This information is considered proprietary and confidential, and I cannot give it away.

I am limited to google, IMO documents, and other public information in trying to come up with information. There isn't much out there because unless you need to know about it, its very boring information to have.--Dj245 20:31, 12 September 2007 (UTC)[reply]

I listed ship articles in Category:Ships with ice classification. Most ships with an article on Wikipedia seem to be in Category:Ships in Ice Class 1A. The only ship with a ABS classification seems to be MV John Hamilton Gray -- Petri Krohn 02:42, 17 September 2007 (UTC)[reply]
This category is far from complete. There are thousands, if not tens of thousands, of ships with ice class. The ice class notation is often not heavilly publicised. Finding these ships without the benefeit of a classification society database is like trying to hunt rabbits by firing a cannon straight up.
Most platform supply vessels have both a firefighting notation and an ice class notation. We do large numbers of these vessels at ABS.
Please note that the Rules HAVE been unified in 2006. All major class societies are now playing by the same rules. Most class societies have what I would call "internal rules" but these rules are just the international rules with the individual class societies own spin on them. The IMO and IACS oversee these rules now and make amendments when required. Older documents may still refer to the way things used to be. The baltic ice classes do not belong to Finland any more than the arctic ones are overseen by ABS. This is like saying the police write the lawbook- it just isn't the case. --Dj245 03:23, 18 September 2007 (UTC)[reply]

Finnish-Swedish ice class

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I changed "Baltic ice classes" to "Finnish-Swedish ice class" as the latter is more commonly used. I also rewrote the section since it contained factual errors and gave some sources (although I'm not sure which is the correct way to refer to the Finnish law in FINLEX - please fix if you know better). Tupsumato (talk) 13:01, 8 April 2010 (UTC)[reply]

Hi
Ice Str (Suitable) ships and Ice Classed ships.
1 - A slight correction is required to the opening lines of the article, as people mix up the terms "ice class" and "ice Strengthned". A ship that is "ice Strengthned" (suitable for passage through ice) may not be "ice classed" (Insured for ice transit).
2 - Here is a copy of a spreadsheet I put together some years ago at the time of the 2006 ice class unification to compare the different ice class notations.
If one of you bright sparks who know how to do nice formatting could put it into the Ice Class article I'd appreciate it.
Approximate correspondence between Ice Classes of the Finnish-Swedish Ice Class Rules
					
(Baltic Ice Classes) and the Ice Classes of other Classification Societies					
					
Classification Society	 		                               Ice Class		

Finnish-Swedish Ice Class Rules	                        IA      IA	IB	IC      Category
                                                        Super                        	II

Russian Maritime Register of Shipping (Rules 1995)	UL	L1	L2	L3	L4

Russian Maritime Register of Shipping (Rules 1999)	LU5	LU4	LU3	LU2	LU1

American Bureau of Shipping	                        IAA	IA	IB	IC	D0

Bureau Veritas	                                        IA 	IA	IB	IC	ID
                                                        Super

CASPPR 1972	                                        A	B	C	D	E

China Classification Society	                        B1*	B1	B2	B3	B

det Norske Veritas	                                ICE-1A*	ICE-1A	ICE-1B	ICE-1C	ICE-C

Germanischer Lloyd	                                E4	E3	E2	E1	E

Lloyd's Register of Shipping	                        1AS	1A	1B	1C	1D

Nippon Kaiji Kyokai	                               IA Super	IA	IB	IC	ID

Registro Italiano Navale 	                        IAS	IA	IB	IC	ID
— Preceding unsigned comment added by Severndroog (talk • contribs) 16:29, 25 October 2011 (UTC)[reply]
Thank you for sharing the information — I put it inside a collapsible box to improve the readability of both the table and the talk page. The Finnish Maritime Administration has compiled a similar equivalence table for HELCOM in 2003. However, I don't think such technical details are absolutely necessary in the general ice class article — perhaps in a separate article about the Finnish-Swedish ice classes some equivalencies to classification society specific notations could be mentioned. As for the terms, "ice class" is commonly used to refer to the level of ice strengthening in the ship and personally I have never seen it used for anything related to insurance. Tupsumato (talk) 20:20, 25 October 2011 (UTC)[reply]
I moved most of the text about Finnish-Swedish ice classes to their own article. I will expand it later. Tupsumato (talk) 21:01, 21 November 2011 (UTC)[reply]
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Ice class comparison table

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The following table about "approximate correspondence between ice classes" was added to the article by 194.26.81.12:

Extended content
Approximate correspondence between ice classes
Classification Society: Finnish-Swedish classification Polar class (IACS) ASPPR (1972) ABS BV DNV GL LR NK RINA RS (1995) RS (1999) KR CCS Ice Conditions Impact limits
Ice Class Icebreaker Multi-year ice with glacial inclusions Repetitive ice impact
PC 1 CAC1 PC 1 POLAR-30 AC3 LL1 LU9 First-year ice with ridges Incidential ice impact
PC 2 CAC1 PC 1 POLAR-20 AC2 LL2 LU8
PC 3 CAC3 PC 3 POLAR-10 AC1.5 LL3 LU7
ICE-15 No ice impact
PC 4 CAC4 PC 4 ICE-10 C1 LL4 LU6
PC 5 PC 5 ICE-05
ICE-1A*F 1 m ice thickness
1A Super PC 6 A 1AA / PC 6 1A SUPER ICE-1A* E4 1AS 1A Super 1AS UL / ULA LU5 ISS B1 1 m ice thickness
1A PC 7 B 1A / PC 7 1A ICE-1A E3 1A 1A 1A L1 LU4 IS1 B1 0,8 m ice thickness
1B C 1B 1B ICE-1B E2 1B 1B 1B L2 LU3 IS2 B2 0,6 m ice thickness
1C D 1C 1C ICE-1C E1 1C 1C 1C L3 LU2 IS3 B3 0,4 m ice thickness
Category II E D0 1D ICE-C E 1D 1D 1D L4 LU1 IS4 B

I reverted this addition as uncited, outdated and factually incorrect, but this was in turn reverted by the original editor. In order to avoid an edit war, let's discuss the issue here before including this (or any) table to the article. My arguments are the following:

  • According to the editor, the table "...is based on the Dutch Wikipedia and on the tables found online". However, only one citation is given and it only covers ice classes up to 1A Super; the part of the table where the correspondence is least reliable (see below) is therefore practically uncited.
  • The information in the table is outdated in many ways: most classification society specific ice classes have been superceded by the IACS Polar Classes, the current RMRS "Ice", "Arc" and "Icebreaker" classes are missing, the merger of DNV and GL is not indicated, and so on.
  • The biggest problem by far is that a reliable comparison of different ice classes can only be done on a case-by-case basis by taking vessel size, hull form etc. into account: an ice class correspondence table developed for a small tugboat would likely look quite different from that of a large tanker. This is due to the different background theories, design scenarios etc.; see this and this presentation for more information and note the remarks adjacent to the correspondence tables. It should also be clearly indicated that the correspondence would be valid only for the ice class rule requirements; it should not be used for actual built vessels which can only be evaluated by comparing the required scantlings to the actual hull structures. Finally, even if it was somehow possible to correct the "ranking" of different ice classes, the last two columns ("ice conditions" and "impact limits") are largely misleading and/or incorrect: for example, the table gives an impression that only a "DNV Icebreaker" is designed to operate in multi-year ice and/or utilize ramming while even PC 1 is limited to first-year ice. Without extensive disclaimers, the table is therefore factually incorrect.

For the above reasons, I strongly oppose including a generalized ice class correspondence table to the article. Tupsumato (talk) 21:12, 15 November 2019 (UTC)[reply]

As mentioned I edited the article based on the Dutch wikipedia as I am currently working in the marine industry and performing design work for which ice class rules need to be taken into account. Each class has his own ice class rating, but in general they are all based on each other and especially on the Finnish-Swedish ice class. Based on the experience I have, I decided to also update the English wikipedia as I know that it can be helpful and to improve the understanding of ice classes and also show which class societies exist including their ratings. At the moment this is all not accounted for in the article and I think this can be a big improvement. Of course the references etc. can be improved, but instead of step by step improving the edit is now deleted and just ignored. Also most of the ice classes are still valid and for example for the Russian ice class the ice class ratings are stated for that year. Tupsumato mentions that the ice class are factually incorrect, although all these ratings have existed and because no exact year is mentioned you cannot say that it is uncorrect, only maybe outdated, but with each others help we can update this to the current applicable ratings.
For me and in my line of work I can see the clear benefit to add this information to this page and therefore I am convinced that this can be of added value. As said, I agree that this table can be improved, but removing it is in my view going backwards instead of going forward. Disclaimers are indeed a good idea and therefore the naming was already changed to "approximate comparison". Maybe that we can come up with a way to show these different ice classes without an exact comparison.
I can search for a lot more references where these comparisons are done, which show to me that there is clearly an overlap between these ratings:

The main problem with an ice class correlation table is clearly apparent on slide 14 of this presentation and slide 11 of this presentation. Compare the correlations presented on the left hand side of both slides: while there are certainly some similarities, there are also quite significant differences particularly on the right hand side of the graphs. As stated in the very same slides, the correspondence of ice classes "depends on ship size, hull form, structural configurations etc." and "correspondence depends on what is assessed". Thus, you can't just simplify and reduce it particularly to a table or grid which gives an impression that one ice class clearly and directly corresponds to another specific ice class. I'm against including such table to Wikipedia because even with extensive disclaimers sooner or later someone will think it's the truth, the whole truth and nothing but the truth. If the industry professionals clearly state that "comparison of ice classes is not easy", we definitely should not give an impression that it can be reduced to a simple table. Notwithstanding the aforementioned, general information about pre-IACS PC ice classes could be described in the article body under "Classification Societies".

For the Finnish-Swedish ice classes, I don't think copying the full Trafi correlation table is very encyclopedic because with few exceptions, it's trivial which classification society specific distinguishing mark corresponds to which Finnish-Swedish ice class. Furthermore, correlation between "obsolete" ice classes and current regulations is presented primarily for administrative purposes such as collection of fairway fees and eligibility for icebreaker assistance in the Baltic Sea. I have now added a sentence which states that sometimes there are differences in notation; if the reader is interested in the topic, the full list can be found in the cited reference.

As for my claim about factual incorrectness, this relates to two specific topics: the generalized correlation between specific ice classes and the columns "Ice Conditions" and "Impact limits". Looks like much of the information comes from the 2007 DNV presentation; not only is it copied incorrectly (e.g. POLAR classes are suitable for operations in multi-year ice), but it is specific to DNV and cannot be generalized to all ice classes. "Icebreaker" is also not a specific ice class, but an additional distinguishing notation that allows more aggressive icebreaking operations.

Tupsumato (talk) 06:56, 19 November 2019 (UTC)[reply]

USCG ice breaker classing

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The USCG like the CCG uses "heavy icebreaker", "medium icebreaker", "light icebreaker"; are they the same capability as the CCG categories already in the article?

If so, it should be so stated, if not, they should be added.

-- 67.70.25.80 (talk) 23:14, 12 August 2023 (UTC)[reply]

The categorization of icebreakers to different classes within the USCG and CCG is not the same as "ice class". Tupsumato (talk) 08:57, 13 August 2023 (UTC)[reply]
No, not whether they are the same as ice class, but whether a Canadian rating of heavy icebreaker is the same as an American rating of heavy icebreaker, etc. This article already lists the Canadian heavy/medium/light icebreaker ratings on the chart -- 67.70.25.80 (talk) 02:51, 14 August 2023 (UTC)[reply]
The article includes description of two Canadian ice class systems (ASPPR and CAC). The CCG classification is incorrect in this context so I have deleted it; the rest of the text should be rewritten as well to reflect e.g. the fact that some of them are no longer in use. As for USCG, I've seen both propulsion power and icebreaking capability used to differentiate between their "medium" and "heavy" icebreakers, but I'm not sure if that's an official way of rating the vessels. Tupsumato (talk) 06:50, 14 August 2023 (UTC)[reply]
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