Wastage allowances for ships under 90 m
Ninety metres is the line most societies draw, and they draw it in four different ways: a separate table, a shared column with larger ships, a percentage added to the standard figures, or nothing at all. This table holds every under-90 m regime found in the documents on file, and records with its clause where a society has none.
- table
- T09
- last verified
- 2026-08-04
- verified by
- —
- cycle
- each class edition, and each January
Does the society draw a line at 90 m, and what happens on the small side of it
Four answers appear. A separate table of its own. A column shared with larger ships. The standard figures adjusted by a stated amount. Or no length distinction at all, in which case the clause proving it is cited. 14 rows · every value carries its clause and PDF page
| Society · structural member | Separate regime under 90 m?yes, shared, adjusted, or none | What the source saysand where the figures sit |
|---|---|---|
| ABSPart 7 — July 2026 | Yes — its own table 7-A1-4/35.3 TABLE 2 · PDF p. 611 | "Individual Wastage Allowances, Conventional Vessels Under 90 Meters (295 Feet)" — eight members at 25 % or 30 %. Aluminium hulls take Table 3, which carries no length limit; yachts of 24 m to 61 m take Table 4. ABS also sets a separate thickness measurement extent for vessels under 90 m at special periodical surveys, and adds hull requirements for vessels under 90 m in unrestricted service. 7-A1-4/35.3 TABLES 2, 3, 4 · PDF pp. 611–612 |
| BVNR467 Part A — R26, July 2026 | Adjusted — the standard figures, plus 5 Pt A Ch 2 App 3 [4.3.6] · PDF p. 146 | BV writes its acceptance criteria for cargo-area structure on a ship longer than 90 m, and then lets the surveyor carry them onto a smaller ship by adding 5 (%) to each tabulated percentage — a 10 % criterion becomes 15 %, and so on. Deck and bottom zone figures are held back from that increase. The same 5 (%) is on offer for structure lying outside the cargo area, and the two reliefs cannot be taken together. The deck and bottom zone exclusion is what protects the hull girder: the zone criteria rest on the current section modulus not falling below 90 % of the rule modulus within 0,4L amidships. Pt A Ch 2 App 3 [4.3.6] · PDF p. 146 |
| CCSTM Guidelines Ver 6.6 — March 2025 | Yes — for named members only Chapter Three §II.2, Table 3.1 · PDF p. 24 | Table 3.1 splits the minimum renewed thickness of structural members in fore peak and aft peak ballast tanks at 90 m. A second split at 90 m governs the renewal thickness of cargo hold hatch coamings on bulk carriers contracted between 1 July 1998 and 1 January 2004. CCS states the criterion as a minimum remaining percentage of original thickness, not as an allowable diminution — read the figures as "renew below this". Chapter Three §II.2 Table 3.1 · PDF p. 24 and §II.3.2 · PDF p. 25 |
| DNVDNV-CG-0182 — Edition July 2022 | older edition — Jul 2022Yes — its own section Sec.2 [2] · PDF p. 9 | older edition — Jul 2022Sec.2 is split into [2] Vessels with length, L < 90 m and [3] Vessels with length, L ≥ 90 m. The under-90 m section is four lines: flat diminution percentages, two minimum-thickness formulas, and a single figure for stainless steel and aluminium. The 90 m and over section runs to hull girder section modulus and ultimate buckling strength. Sec.2 applies to main class notation 1A and excludes container ships, naval vessels, high speed and light craft, yachts, aluminium vessels and vessels with class notation CSR. Sec.2 [2] and [3] · PDF p. 9 |
| INSBPart I — December 2024 | Both — a column of its own in one table, shared in the other Pt I Ch 3 Sec 13 Tables C and D · PDF pp. 82–83 | Category 3 is all ship types having a length L < 90 metres. Table D, maximum reduction of topside and bottom areas at transverse sections, gives Category 3 its own pair of columns. Table C, maximum reduction of individual plates and stiffeners, merges Category 2 and Category 3 into one column. Table D Note 4 allows a greater reduction over 0.5L amidships against a 90 % section modulus check for Categories 1 and 2 only. Category 3 is left out of that relief. Pt I Ch 3 Sec 13 Table D Note 5 · PDF p. 83, Tables C and D · PDF pp. 82–83 |
| KRRules Part 1 — 2026 edition | Yes — by class band rather than by length directly Pt 1 Annex 1-5 Table 1, Note 1 · PDF p. 277 | Class I is ships of length 90 m and above classed with Classification Survey during Construction after 1 July 1998, or ships carrying liquid cargo classed the same way. Class II is ships other than Class I and Class III. A steel ship under 90 m that does not carry liquid cargo therefore falls into Class II, which carries the more generous wear limits throughout Table 1. Class III is steel craft to the Rules for High Speed and Light Crafts, with a flat wear limit. For ships classed through Classification Survey after Construction, separate requirements specified by the Society apply. Pt 1 Annex 1-5 Table 1, Note 1 · PDF p. 277 |
| LRTM and Close-up Survey Guidance Part 1 — Ver 7.3 | older edition — Nov 2016 v7.3A category of its own, but a shared column Pt 1 Ch 5 Sec 1 §1.5 · PDF p. 25 | older edition — Nov 2016 v7.3Category 3 is all ship types having a length L less than 90 metres. Every table that follows sets Category 3 alongside Category 2: Table 1.5.4 is headed "General Dry Cargo Ships and All Other Category 2 & 3 Type Ships", and Table 1.5.5 gives one shared "Category 2 & 3 ships" column. No figure in the held edition applies to Category 3 alone. L here is the Rule length, which LR fixes in the Rules for Ships at Part 3, Chapter 1.6.1. Pt 1 Ch 5 §1.5 · PDF p. 25, Table 1.5.4 · PDF p. 31, Table 1.5.5 · PDF p. 32, Note 5 · PDF p. 33 |
| ClassNKGuidance for Undergoing Class Maintenance Surveys | older edition — 2014No separate regime Appendix 3.5 (1) · PDF p. 177 | older edition — 2014The wastage allowance table is written by structural member only — shell plates, deck plates, floors and girders, hatch covers and so on. No length threshold, no ship-size column and no small-ship note appears anywhere in Appendix 3.5. Item (1) prints five numbered items, (i) to (v), above the table rather than under it. Item (i) is introductory and does no more than announce the table; the four that qualify it are (ii) longitudinal strength, (iii) uniform wear, (iv) local corrosion, and (v) ships under the retroactive requirements for existing bulk carriers, which are assessed one ship at a time. The high tensile steel rule is not among them: it is a subsection of its own, item (2). Item (iv) is the one a surveyor reaches for most often: pitting and stress corrosion are left to the Surveyor's discretion, with 40 % of the original thickness given as the standard limit for local corrosion other than stress corrosion. Appendix 3.5 (1)(i) to (v) and (2) · PDF p. 177 |
| ClassNKRules and Guidance, Part B — Class Surveys | older edition — 2022No separate regime Pt B Tables B1.3.1-1(a) to (d) · PDF pp. 446–447 | older edition — 2022Tables B1.3.1-1(a) to (d) give the corrosion addition t_c for steel hatch covers and coamings by type of structure, feeding t_renewal = t_as-built − t_c + 0.5 mm, and they are keyed to contract date and to whether the ship is built under Part CSR-B or CSR-B&T. No 90 m threshold appears in them. Pt B Tables B1.3.1-1(a) and (b) · PDF p. 446 |
| PRSPart I — January 2026 | not published Pt I, report forms TM1-G to TM7 · PDF pp. 100–111 | Part I publishes no wastage allowance figures at all, for any ship size. Every thickness measurement report form carries a "Maximum Allowable Diminution" column and the standing note that "the maximum allowable diminution could be stated in an attached document". The figure is therefore issued per ship, not per rule. Searched: the whole of Part I. Substantial corrosion is defined in Chapter 1, and the measurement pattern in §5.1.3.7, but no allowance table appears. Pt I §5, report forms and their notes · PDF pp. 100–111 |
| RINAPart A Ch 2 App 2 — 1 July 2024 | older edition — 1 Jul 2024Adjusted — the standard figures, plus 5 Pt A Ch 2 App 2 [4.3.6] · PDF p. 13 | older edition — 1 Jul 2024RINA [4.3.6] and BV [4.3.6] carry the identical provision. The criteria are written for cargo-area structure on a ship above 90 m in length; below that length every tabulated percentage may be lifted by 5 (%), deck and bottom zones excepted; structure outside the cargo area earns the same 5 (%); and the two reliefs cannot be claimed at once. The buckling strength criterion of [4.4.1] draws a second, higher line: it applies only to ships having a length greater than 120 metres. Pt A Ch 2 App 2 [4.3.6] · PDF p. 13 |
| IACS Common Structural RulesBulk carriers and double hull oil tankers | N/A — under 90 m is outside the Rules Pt 1 Ch 1 Sec 1 [1.2.1] and [1.3.1] · PDF pp. 21–22 | The Rules apply to bulk carriers of freeboard length L_LL of 90 m or above and to double hull oil tankers of L_LL of 150 m or above. Ships outside the Rules are to comply with the relevant Rules of the Society, so no CSR wastage arithmetic reaches an under-90 m ship. Pt 1 Ch 1 Sec 1 [1.2.1], [1.3.1] and [1.1.3] · PDF pp. 21–22 |
| IACS UR Z7Hull classification surveys | not published §1.2.8 · PDF p. 5, Table 1 · PDF pp. 16–17 | Z7 publishes no wastage allowance of any kind, for any ship length. Its definition of substantial corrosion refers to "allowable margins" without stating them, and the survey report forms send the reader to "substantial corrosion allowable limits, according to the individual classification Society's Rules". §1.2.8 · PDF p. 5, with the report form notes · PDF pp. 42–48 |
| IACS UR Z10 seriesZ10.1 to Z10.5, ESP ship types | not published §1.2.11 · PDF p. 7 | The Z10 series sets survey scope, close-up survey extent, thickness measurement extent and the expansion tables. It publishes no allowable margin, so it carries no length threshold for one. The ESP ship types it covers are in any case large ships. §1.2.11 · PDF p. 7, with Table II referenced at §2.4.1 · PDF p. 14 |
ABS Appendix 7-A1-4/35.3 — the small-ship and light-alloy tables
Percentages are applied to the as-built thickness for unconverted, conventional type vessels built to ABS Class. Table 2 is steel and limited to vessels under 90 m; Table 3 is aluminium and carries no length limit; Table 4 covers yachts of 24 m to 61 m. 14 rows · every value carries its clause and PDF page
| Society · structural member | TABLE 2 — steelconventional vessels under 90 m (295 ft), 2016 | TABLE 3 — aluminiumconventional vessels built to ABS Class, 2025 | TABLE 4 — yachtssteel or aluminium, 24 m (79 ft) to 61 m (200 ft) |
|---|---|---|---|
| Main Deck Plating | 25% 7-A1-4/35.3 TABLE 2 · PDF p. 611 | 15% 7-A1-4/35.3 TABLE 3 · PDF p. 611 | N/A Table 4 lists no deck member under this name; it splits by framing direction. 7-A1-4/35.3 TABLE 4 · PDF p. 612 |
| Bottom Plating | 25% 7-A1-4/35.3 TABLE 2 · PDF p. 611 | 15% 7-A1-4/35.3 TABLE 3 · PDF p. 611 | N/A 7-A1-4/35.3 TABLE 4 · PDF p. 612 |
| Keel Plating | 25% No keel condition attaches to this figure. Table 2 carries Notes 1 to 5 and not one of them mentions the keel. The rule that a keel plate goes for renewal once it falls to the thinnest the bottom plating beside it is allowed to be belongs to the 90 m and over tables only — Note 8 of TABLE 1A at PDF p. 606, Note 6 of TABLE 1B at PDF p. 608 and Note 7 of TABLE 1C at PDF p. 610. 7-A1-4/35.3 TABLE 2 · PDF p. 611 | 15% 7-A1-4/35.3 TABLE 3 · PDF p. 611 | N/A 7-A1-4/35.3 TABLE 4 · PDF p. 612 |
| Sheer Strake | 25% 7-A1-4/35.3 TABLE 2 · PDF p. 611 | 15% 7-A1-4/35.3 TABLE 3 · PDF p. 611 | N/A 7-A1-4/35.3 TABLE 4 · PDF p. 612 |
| Bilge Strake | 25% 7-A1-4/35.3 TABLE 2 · PDF p. 611 | 15% 7-A1-4/35.3 TABLE 3 · PDF p. 611 | N/A 7-A1-4/35.3 TABLE 4 · PDF p. 612 |
| Side Shell Plating | 30% 7-A1-4/35.3 TABLE 2 · PDF p. 611 | 20% 7-A1-4/35.3 TABLE 3 · PDF p. 611 | N/A 7-A1-4/35.3 TABLE 4 · PDF p. 612 |
| Forecastle | 30% 7-A1-4/35.3 TABLE 2 · PDF p. 611 | 20% 7-A1-4/35.3 TABLE 3 · PDF p. 611 | N/A 7-A1-4/35.3 TABLE 4 · PDF p. 612 |
| Internals and Bulkheads | 30% An internal member counts towards longitudinal strength only where it runs continuously, or is effectively developed at its ends, right through the 0.4L amidships region. 7-A1-4/35.3 TABLE 2 · PDF p. 611 | 20% 7-A1-4/35.3 TABLE 3 · PDF p. 611 | N/A 7-A1-4/35.3 TABLE 4 · PDF p. 612 |
| Longitudinally Framed Shell and DecksYacht table only | N/A 7-A1-4/35.3 TABLE 2 · PDF p. 611 | N/A 7-A1-4/35.3 TABLE 3 · PDF p. 611 | 15% Conditional. The figure holds only where permanent set in the strength deck plating stays at or below s/100 and no frame, longitudinal or beam is found deformed; s is the stiffener spacing. Beyond that, ABS sends the Surveyor to a technical office for guidance. 7-A1-4/35.3 TABLE 4 · PDF p. 612 |
| Transversely Framed Shell and DecksYacht table only | N/A 7-A1-4/35.3 TABLE 2 · PDF p. 611 | N/A 7-A1-4/35.3 TABLE 3 · PDF p. 611 | 10% Conditional. The figure holds only where permanent set in the strength deck plating stays at or below s/150 and no frame, longitudinal or beam is found deformed; here s is the frame spacing. Beyond that, ABS sends the Surveyor to a technical office for guidance. 7-A1-4/35.3 TABLE 4 · PDF p. 612 |
| Other Internal Structure and External Structure Providing Weathertight Integrity to the HullYacht table only | N/A 7-A1-4/35.3 TABLE 2 · PDF p. 611 | N/A 7-A1-4/35.3 TABLE 3 · PDF p. 611 | 15% 7-A1-4/35.3 TABLE 4 · PDF p. 612 |
| Hull girder check that sits over the tableSatisfying the member percentages is not enough on its own | The member percentages are the minimum for individual members and plates; on top of them the hull girder section modulus has to hold at 90 % or more of the larger of two required values — the modulus required when the ship was built, and the modulus the ABS Rules for Building and Classing Marine Vessels call for at 3-2-1/3.1. 7-A1-4/35.3 TABLE 2, Notes 2 and 3 · PDF p. 611 | not published Table 3 carries no notes of its own; the only sentence under it directs vessels built to other society rules to the Technical Office. 7-A1-4/35.3 TABLE 3 · PDF p. 611 | not published The three notes to Table 4 cover fairing filler and permanent set, not hull girder strength. 7-A1-4/35.3 TABLE 4, Notes 1–3 · PDF p. 612 |
| Extra limit below 61 mA second length threshold inside the under-90 m table | Below 61 m (200 feet), and only there, deck or bottom area may lose at most 20 percent of the Rule required area 7-A1-4/35.3 TABLE 2, Note 4 · PDF p. 611 | N/A 7-A1-4/35.3 TABLE 3 · PDF p. 611 | N/A 7-A1-4/35.3 TABLE 4 · PDF p. 612 |
| Vessels built to another society's rulesPrinted under both Table 2 and Table 3 | ABS publishes no figure. The allowance comes from whichever Technical Office ran the initial plan review, and it may be set from the requirements of the previous society 7-A1-4/35.3 TABLE 2 and Note 5 · PDF p. 611 | Same answer under Table 3 — ask the Technical Office that ran the initial plan review for the allowance 7-A1-4/35.3 TABLE 3 · PDF p. 611 | not published 7-A1-4/35.3 TABLE 4 · PDF p. 612 |
INSB Category 3 — ships under 90 m, maximum reduction of topside and bottom areas
Table D is the only table in the documents on file that gives ships under 90 m a column entirely of their own. Each figure caps an average, not a spot reading: the reduction is averaged across the plates or the longitudinals lying in a topside or a bottom area, taken at a transverse section. Values between the two columns come from linear interpolation. 7 rows · every value carries its clause and PDF page
| Society · structural member | Over 0.5L amidshipsCategory 3 — L < 90 m | At 0.075L from endsCategory 3 — L < 90 m |
|---|---|---|
| Topside areas — PlatingWhat counts as topside area: the deck — on a dry cargo ship only the part outside the line of openings — together with the stringer and the sheer strake, rounded gunwales included, and the longitudinals that go with them | 15% Pt I Ch 3 Sec 13 Table D · PDF p. 83 | 30% Pt I Ch 3 Sec 13 Table D · PDF p. 83 |
| Topside areas — Longitudinals | 20% Pt I Ch 3 Sec 13 Table D · PDF p. 83 | 30% Pt I Ch 3 Sec 13 Table D · PDF p. 83 |
| Bottom areas — Plating, single bottom constructionBottom area means the keel, the bottom and bilge plating, and the longitudinals attached to them | 15% Pt I Ch 3 Sec 13 Table D · PDF p. 83 | 30% Pt I Ch 3 Sec 13 Table D · PDF p. 83 |
| Bottom areas — Plating, double bottom construction | 20% Pt I Ch 3 Sec 13 Table D · PDF p. 83 | 30% Pt I Ch 3 Sec 13 Table D · PDF p. 83 |
| Bottom areas — Longitudinals | 20% Pt I Ch 3 Sec 13 Table D · PDF p. 83 | 30% Pt I Ch 3 Sec 13 Table D · PDF p. 83 |
| When the reduction runs past three quarters of these figuresA trigger inside the table, separate from substantial corrosion | Once plating or longitudinals in a topside or a bottom area run past 0.75 of the tabulated figure, the Surveyor calls for further transverse sections and those are measured too Pt I Ch 3 Sec 13 Table D, Note 6 · PDF p. 83 | Same note, both columns Pt I Ch 3 Sec 13 Table D, Note 6 · PDF p. 83 |
| Relief not offered to Category 3The section modulus route out of the amidships figures | Categories 1 and 2 may be let past the tabulated figure over 0.5L amidships on one condition: the hull girder section modulus worked out from the actual gauged thicknesses stays at 90 % or above of what the Rules asked of the ship when new. Where that relief is asked for, the scantlings have to be reassessed. Category 3 is not named. Pt I Ch 3 Sec 13 Table D, Note 4 · PDF p. 83 | N/A The note is written for the amidships figures only. Pt I Ch 3 Sec 13 Table D, Note 4 · PDF p. 83 |
The remaining under-90 m figures, one source at a time
DNV, KR, BV, RINA and CCS each give the small ship something different: flat percentages with a minimum thickness formula, a class band, an adjustment to the standard figures, and a member-specific split. 15 rows · every value carries its clause and PDF page
| Society · structural member | The figure, as printedwith the condition it carries |
|---|---|
| DNV — plates, L < 90 mMain class notation 1A, steel, no major conversion | older edition — Jul 2022Allowable diminution up to 20 % may be accepted Sec.2 [2] · PDF p. 9 |
| DNV — stiffeners, L < 90 m | older edition — Jul 2022Allowable diminution up to 25 % may be accepted Sec.2 [2] · PDF p. 9 |
| DNV — stainless steel or aluminium, L < 90 mPlates and stiffeners alike | older edition — Jul 202210 % Sec.2 [2] · PDF p. 9 |
| DNV — minimum thickness, weather and strength deck, L < 90 mThe percentage is capped by an absolute floor | older edition — Jul 2022t_min = 4.5 + 0.02 L √k, mm k is the material factor — 1.0 where the steel is mild — and DNV-RU-SHIP Pt.3 Ch.3 Sec.1 [2] is where it is defined. The formula is set as an image in the source, PDF p. 9, with no text layer behind it, and was read off the page visually. Sec.2 [2] · PDF p. 9 |
| DNV — minimum thickness, bottom and bilge, L < 90 m | older edition — Jul 2022t_min = 4.5 + 0.035 L √k, mm set as an image in the source, PDF p. 9, with no text layer behind it, and read off the page visually. Sec.2 [2] · PDF p. 9 |
| KR Class II — strength deck plating, sheer strake and their longitudinals, shell plating, bottom shell plating, deep tank bulkhead plating, topside and hopper side sloping plating, inner bottom platingClass II is where a steel ship under 90 m that does not carry liquid cargo lands | (20 % of original thickness) + 1 mm Class I, being ships of 90 m and above and liquid cargo ships, takes 20 % of original thickness with no added millimetre. Pt 1 Annex 1-5 Table 1 · PDF p. 277 |
| KR Class II — floor and girder of double bottom, web and face of primary supporting member | 25 % of original thickness Class I: 20 % of original thickness. Pt 1 Annex 1-5 Table 1 · PDF p. 277 |
| KR Class II — effective deck and superstructure deck plating; deck plating within the line of the cargo hatch openings; watertight bulkhead plating apart from deep-tank bulkheads; hatch covers and hatch coamings, stiffeners included; and the webs, faces and brackets of secondary stiffenersA secondary stiffener is one carried by a primary supporting member that carries no further member itself | 30 % of original thickness Class I: 25 % of original thickness. Pt 1 Annex 1-5 Table 1 · PDF p. 277 |
| KR Class II — web, face and brackets of frames in cargo hold or tankTwo limits, the greater governs | 25 % of original thickness or 2.5 mm, whichever greater Class I: 20 % of original thickness or 1.5 mm, whichever greater. Pt 1 Annex 1-5 Table 1 · PDF p. 277 |
| KR Class II — partial corrosion, for example pitting | 35 % of original thickness Class I: 30 % of original thickness. Pt 1 Annex 1-5 Table 1 · PDF p. 277 |
| KR Class III — every member in the tableSteel craft to the Rules for High Speed and Light Crafts | 1 mm One merged cell spanning all member rows — an absolute limit, not a percentage. Pt 1 Annex 1-5 Table 1 · PDF p. 277 |
| BV — the small-ship increase, L under 90 mReaches the isolated area, item, group and zone criteria of the wastage tables alike | Add 5 (%) to each tabulated wastage percentage — a 10 % criterion becomes 15 %, and so on — everywhere but the deck and bottom zones The same 5 (%) is offered a second way, for structure outside the cargo area; a ship cannot take both at once. Pt A Ch 2 App 3 [4.3.6] · PDF p. 146 |
| RINA — the small-ship increase, L under 90 m | older edition — 1 Jul 2024Add 5 (%) to each tabulated wastage percentage — a 10 % criterion becomes 15 %, and so on — everywhere but the deck and bottom zones The buckling strength criterion of [4.4.1] starts at a length above 120 metres, so it does not reach an under-90 m ship either. Pt A Ch 2 App 2 [4.3.6] · PDF p. 13 |
| CCS — structural members in fore peak and aft peak ballast tanks, L < 90 mStated as the minimum thickness that may remain, not as the wastage that may be lost | 70 % minimum renewed thickness L ≥ 90 m takes 75 %. CCS states the clarification exists because no specific corrosion limit for interior members of peak ballast tanks is defined in the CCS Rules themselves. Chapter Three §II.2 Table 3.1 · PDF p. 24 |
| CCS — cargo hold hatch coaming renewal thickness, L < 90 mBulk carriers whose construction contract was signed on or after 1 July 1998, and before 1 January 2004 | 70 % L ≥ 90 m takes 75 %. Ships contracted on or after 1 January 2004 are assessed against IACS UR S21.6.2 instead, which carries no 90 m split. Chapter Three §II.3.2 · PDF p. 25 |
Where the line sits. Ninety metres is a rule length, not an overall length, and each society defines it in its own scantling part — LR names Part 3 Ch 1.6.1 of the Rules for Ships, DNV uses its rule length L, ABS states the figure in metres and in feet (90 m / 295 ft). Check which length the ship's documents record before deciding which regime applies. Correction to a common assumption. ABS Appendix 7-A1-4 does not carry a separate aluminium table for ships under 90 m. In the July 2026 edition, Table 2 is "Individual Wastage Allowances, Conventional Vessels Under 90 Meters (295 Feet)" and is steel; Table 3 is "Aluminum Wastage Allowances, Conventional Vessels built to ABS Class (2025)" and carries no length limit at all; Table 4 covers steel or aluminium yachts of 24 m to 61 m. Under 90 m is outside CSR. The Common Structural Rules apply to bulk carriers of freeboard length 90 m and above and to double hull oil tankers of 150 m and above, so no under-90 m ship is a CSR ship and none of the t_ren arithmetic applies to one. What IACS does not publish. Neither UR Z7 nor the UR Z10 series publishes a wastage allowance of any kind. They set the survey and measurement extent and leave the allowable margins to each Society, which is why the numbers below differ from society to society for the same plate. Editions. Rows carrying an older-edition badge were read from the edition named on the cell; a newer edition exists and sits behind a member login.