Anatomy of a comment sheet

A comment sheet is a formal document issued by a classification society following its review of a drawing or document submitted for class approval. When a design office submits a drawing, the surveyor or plan approval engineer examines it against the applicable rules, standards, and any flag-state requirements. Where the submission does not satisfy those requirements, or where clarification is needed, the society raises comments. The comment sheet is the instrument through which those comments are communicated to the design office. It is not an informal note; it is a tracked record in the approval process, and every comment on it requires a formal response before the drawing can be approved.

Comment sheets arrive at intervals determined by the submission schedule of the project. On a typical newbuild, a design office will make dozens of drawing submissions across structural, machinery, electrical, and outfitting disciplines, and most of those submissions will return at least one round of comments. Major structural drawings — midship sections, transverse bulkheads, hatch covers — commonly go through two or three review cycles. Across a full newbuild project, the total number of individual comments addressed can run into the hundreds. The comment sheet arrives after the society has completed its review, which may take days to several weeks depending on the drawing complexity and the society's workload. The office should not treat the interval between submission and comment return as idle time; the discipline lead will normally be refining downstream drawings that depend on the same structural or systems logic.

The content of a comment sheet follows a consistent structure across most classification societies, though the exact layout varies. Each comment is assigned a sequential number within the document, which becomes the primary reference for tracking. The sheet identifies the drawing or document under review by its number and title, and records the revision of that drawing that was submitted — a detail that matters later when a revised drawing is issued. Each comment is assigned a discipline tag, such as structural, machinery, electrical, stability, or fire safety, reflecting which branch of the society's technical department raised it. The comment text itself states what is missing, what is incorrect, or what additional information the society requires. Many comments include a rule reference — a specific paragraph of the classification rules, a referenced standard, or a statutory instrument — that grounds the comment in a defined requirement. Not all comments cite a rule; some request clarification or ask the office to demonstrate compliance by calculation or by reference to an approved document.

The design office's formal response to each comment is called a disposition. A disposition is not optional and it is not a narrative reply; it is a structured statement that resolves the comment within the approval record. The three standard disposition positions are: accepted, where the office agrees with the comment and will revise the drawing accordingly; not accepted, where the office disagrees with the comment and provides a technical justification for maintaining the current design; and revised as noted, used when the office has already incorporated the required change into the drawing being returned. The disposition must be complete enough that the reviewing surveyor can close the comment without needing to correspond further. Vague dispositions — acknowledging the comment without committing to a specific action — will generally result in the comment remaining open.

Each disposition position has different implications in practice. An accepted disposition commits the office to making a specific change. That change must appear in the next revision of the drawing, and the comment sheet will be checked against that revision when it is submitted. A not-accepted disposition triggers a technical exchange: the office's justification is reviewed by the society, which may accept the argument, modify its position, or maintain the comment as open. This exchange can take more than one cycle and requires the discipline lead to prepare a substantive technical response, often with supporting calculations or reference to an accepted alternate standard. The not-accepted route is not inherently adversarial, but it carries obligation — the justification must be specific, technically grounded, and referenced to an identifiable source.

Close-out is the process by which each comment is formally resolved and the drawing moves toward approval. A comment is considered closed when the society's reviewer confirms that the disposition is satisfactory and that any required changes have been incorporated correctly in the revised drawing. Close-out typically occurs when the office returns a marked-up drawing or a revised drawing revision accompanied by a completed disposition table. The society reviews each comment against the returned material and marks it closed in its own tracking record. If the society does not accept a disposition — because the justification is insufficient, the promised change was not reflected in the drawing, or a new issue was introduced by the revision — the comment remains open and the drawing cannot proceed to approval in that state.

An open comment carries a concrete obligation that does not expire with the review cycle that generated it. If a comment remains open when the project reaches the next formal milestone — a subsequent design review stage, a flag-state submission, or a class survey — it must be resolved before that stage can be closed. Open comments from an early stage that have not been addressed by the time the project progresses accumulate risk: they may block certificate issuance, trigger additional survey requirements, or require rework of drawings that were otherwise finalised. The discipline lead is responsible for knowing the open status of every comment in their area. Treating open comments as a background administrative matter rather than a live engineering obligation is the most common way a comment register becomes a critical-path problem late in a project.

Class comments almost always trigger a drawing revision. The revision cycle works as follows: the original submission is, say, revision B. The society comments on revision B. The office prepares revision C, incorporating the accepted changes, and returns it alongside the disposition table. The comment sheet references revision B because that is what was reviewed; the close-out assessment will compare the revision C drawing against the revision B comments to confirm each is addressed. If revision C introduces new content beyond what was required to address the comments, the society may flag that new content for additional review, which is why some offices prefer minimal revisions that address only the open comments rather than incorporating unrelated design development. The revision number recorded on the comment sheet is therefore a fixed reference — it does not update when a new revision is issued — and both the office and the society use it to anchor the comment to the state of the design at the time it was raised.

Unanswered comments do not quietly lapse between design review stages. When a drawing with open comments is included in a subsequent submission — whether because the drawing has been updated for other reasons or because the project has advanced to a later approval stage — the society will carry forward all unresolved comments from prior reviews. The new submission does not reset the comment record. The reviewer will expect to see dispositions on every prior open comment before they will process any new comments raised on the updated drawing. In practice this means that an office carrying open comments into a later stage faces a compounded review burden: the society must close the legacy comments and then assess the new revision, which extends the review timeline. The discipline lead who keeps the comment register current and closes comments promptly, cycle by cycle, is doing work that is invisible when it goes well and very visible when it does not.

There is a dimension of disposition strategy that the mechanics above do not fully capture. An office that accepts every comment and revises sends a consistent signal to the reviewing surveyor: every comment was correct. An office that uses not-accepted dispositions precisely — backed by rule references, precedent, and a specific technical argument — builds a track record of successful challenges over time. That track record is not formally logged by the class society, but it is accumulated. Surveyors form views about the quality of the submissions they review and the rigour of the arguments they receive. An office that challenges weak comments and wins those challenges, project after project, earns a kind of technical standing that a flawless record of accepted comments does not. Principals who have watched both patterns play out across a career know which one produces better approval outcomes. So do the surveyors.