Cargo Grade Change Procedure Checklist

It covers the operational steps used to change from one cargo grade to another on a gas carrier. The checklist includes liquid freeing, inerting, aeration, purging, and inhibitor injection, with room for cargo-specific limits and verification steps. It is meant to document the sequence and confirm each step before the next one starts.

Use it whenever the vessel is changing cargo grades and the tanks, lines, or associated systems must be prepared for the next product. It is especially useful when the previous cargo and the next cargo have different compatibility, contamination, or safety constraints. It should not replace the vessel's approved cargo manual, terminal instructions, or company procedures.

The DRI is usually the officer or operations lead responsible for the cargo changeover, with execution supported by the deck team and verified by the responsible officer. The exact assignment should follow the vessel's chain of command and company policy. For a system template, let the tenant assign the DRI at import time rather than hard-coding a role.

It is typically recurring only when a cargo grade change is planned, so the recurrence should be event-based rather than a fixed calendar cadence. If your operation uses scheduled trade patterns, you can clone the template for each planned changeover window. Avoid setting a weekly recurrence unless the vessel actually performs that work on a weekly basis.

Common misses include skipping a verification step after inerting, starting aeration before the tank atmosphere meets the required condition, and applying the wrong cargo-specific limit. Another frequent issue is combining multiple actions into one checklist item, which makes it hard to confirm what was actually done. This template keeps each item independently verifiable so gaps are easier to catch.

The template should include fields or checklist items for the limits that matter to the cargo being handled, such as butadiene, VCM, or ammonia requirements. Those limits should be reviewed against the approved cargo manual and site or vessel procedures before use. If a limit does not apply to the current cargo pair, mark it N/A rather than deleting the control.

Yes. You can adapt the checklist items to match tank design, line configuration, instrumentation, and terminal handover requirements. Keep the core sequence intact, but tailor the verification steps, limits, and sign-off points to the vessel and cargo family. That makes the template reusable without turning it into an ad-hoc note.

A checklist reduces reliance on memory and makes the sequence visible to everyone involved. It also creates a clear record of what was verified, what was blocked, and what still needs action before the next step. Compared with an informal log, it is easier to audit, easier to hand off, and less likely to miss a critical control.

Useful integrations include document links for the cargo manual, attachments for gas readings or certificates, and task routing for approvals or hold points. If your workflow supports it, connect the checklist to incident or deviation tracking so any out-of-limit reading becomes a follow-up task. That keeps the procedure tied to action instead of leaving exceptions in comments.