IACS Nears Completion of Requirements

Shipowners want stronger ships. Regulators want stronger ships. Both want new requirements to apply across the industry - a level playing field. In response, the 10 Members of the International Association of Classification Societies (IACS) are progressing technical programs that will lead to more uniform scantling requirements and wastage limits for bulk carriers, oil tankers and, eventually, other ship types. At Posidonia, IACS Chairman Igor Ponomarev outlined work in progress that will culminate in new Unified Requirements (URs) for stronger vessels. For bulk carrier newbuildings, a major initiative - concerned with strength and safe operation - consists of new, harmonized design loading conditions and notations so as to provide increased transparency of the operating capabilities and limits of bulk carriers. This work, which has been developed in response to and in communication with owners’ associations, is near to completion. IACS Council is considering a new UR which, when adopted, will be published on the IACS Website, that will specify the following notations and annotations: BC-A: for bulk carriers designed to carry dry bulk cargoes of cargo density 1.0 tonne/m3 and above with specified holds empty in addition to BC-B conditions BC-B: for bulk carriers designed to carry dry bulk cargoes of cargo density 1.0 tonne/m3 and above with all cargo holds loaded in addition to BC-C conditions BC-C: for bulk carriers designed to carry dry bulk cargoes of cargo density less than 1.0 tonne/m3 The new UR provides for additional notations and annotations giving further detailed description of limitations to be observed during operation as a consequence of the loading condition applied during the design in specified cases. In addition, the UR will clarify the general design loading conditions for all notations and specify ballast conditions. This initiative, concerned with newbuildings, complements IACS’ eight-point action plan for existing bulk carriers which, inter alia, accelerates the schedule for strengthening of the foremost cargo hold’s transverse corrugated bulkhead and double bottom, addresses the strength of the side structure in cargo holds, increases requirements for forward hatch covers, requires the installation of improved bulwarks or breakwaters when ships are not fitted with a forecastle and further increases the requirements of the IACS Enhanced Survey Program earlier in the service life of these ships. Some of the requirements in this package will also apply to new tonnage. For example, in the case of newbuildings, it is expected that forecastles will be required. Meanwhile, IACS’ full reassessment of the strength requirements for hatch cover scantlings (UR S21) – the central recommendation of the Re-opened Formal Inquiry into the loss of the bulk carrier Derbyshire, is now well advanced. Completion of this work is expected in August. The results will be submitted to the IMO. Work is also progressing on a longer term project aimed at increased harmonization of scantling requirements for bulk carrriers and tankers. As a first step, each IACS member is performing scantling evaluations for two “study ships” – a VLCC and a Panamax bulk carrier – to identify the minimum scantlings required to satisfy its Rules. These comparative results will identify the areas of substantial similarities and differences amongst IACS members. The comparative study work is well under way and should be completed later this year. Work will then focus on developing a refined plan for the development of new unified requirements and the formulation of unified minimum scantling requirements for midship scantlings for tankers and bulk carriers. The net scantling approach will be used in the development of these new unified requirements. In this approach, the minimum required scantling for new construction is the net scantling plus a corrosion addition. The IACS Chairman said: “This is an extremely important advance. We hope to have some of the new higher strength, minimum scantling URs ready for consideration by IACS Council by mid-2004. Work in this area is extremely challenging, yet progress is being made. The significance of the project centres on the fact that, at present, each classification society applies its own structural evaluation criteria to determine minimum scantling requirements. Although there are URs governing longitudinal strength that are currently applied by all IACS societies, the minimum scantlings are, at present, sufficiently different to encourage efforts by some shipyards to seek approval of ever lower steel weights for new construction. “Safety may be compromised if commercial parties remain free to ‘shop around’ for lower cost solutions for newbuildings which, in some cases, can undermine prudent standards of structural strength. The new IACS URs will largely remove the potential for such undesirable practices. In taking action, we are responding decisively to calls by shipowners’ associations and other parties for an end to competition on standards to achieve ever lower steel weights.” Other IACS initiatives now in progress and concerning vessel strength include: • A comprehensive revision of UR S11, the longitudinal strength standard with a net scantling approach. Work in this area has the aim of developing requirements for hull girder loads and yielding checks for bending moments and shear forces, together with ultimate strength checks. This task is targeted for completion by the third quarter of next year. • New specifications for HT 40 hull structural steels of thicknesses up to 100 mm. The specifications form part of a new revision of UR W11, which is expected to be adopted this month by the IACS Council. A number of these projects are being taken forward by IACS’ Working Party (Strength). In due course, the Working Party will also submit proposals for a uniform, transparent approach to allowable wastage allowances to achieve uniform scantling renewal requirements amongst IACS societies for use with the new unified minimum required scantlings for new construction. The proposals will be considered for adoption by the IACS Council and for incorporation into the Rules of IACS societies. Igor Ponomarev says: “The uniform wastage allowances will be based on an analysis of over half a million sets of corrosion data concerning the structural elements of bulk carriers and oil tankers, contributed by all IACS societies. The collation and analysis of the data sets was undertaken within a project that began in 1995 and predates the current initiatives for stronger vessels.” The IACS Chairman concludes: “In all areas concerned with the strength of vessels, IACS will continue in its leadership role and will continue to support the IMO’s important work in many related areas. IMO Secretary-General William O’Neil recently stressed the importance of the industry moving ahead on a joint basis. We share this objective.”