Bunker Knowledge Base

Bunker Guides & Insights

Practical reference for bunker buyers, charterers, and vessel operators. Regulations, specifications, procedures, and operational guidance written for working professionals.

6 min read

IMO 2020 Sulphur Cap — What It Means for Bunkering

The IMO 2020 regulation capped marine fuel sulphur at 0.50% globally — a transformation of the bunker market. What happened, how compliance works, and what the ongoing implications are.

7 min read

ISO 8217 Marine Fuel Specifications — Practical Guide

ISO 8217 is the global specification standard for marine fuels. What the key parameters mean in practice and how to read a bunker quality certificate.

8 min read

The Bunkering Procedure — Step by Step

A practical overview of how a bunker delivery actually happens — from nomination to final quantity agreement — and where the operational and commercial risks sit.

4 min read

Bunker Delivery Note (BDN) — What It Contains and Why It Matters

The BDN is the primary regulatory document for a bunker delivery. What information is required, how to handle it, and the retention obligations that follow.

5 min read

Bunker Quantity Surveys — Why and When to Appoint One

A quantity survey is an independent witness to the bunker delivery. When they're worth paying for and what they actually do.

6 min read

Fuel Quality Testing — Pre-Bunker, Post-Bunker, and Dispute

How fuel quality testing actually works — which labs, which tests, what the results tell you, and how they're used in disputes.

5 min read

How to Choose a Bunker Supplier — What Actually Matters

Beyond price per tonne. The factors that separate a supplier who creates value from one who creates problems.

7 min read

EU ETS and FuelEU Maritime — What Every Bunker Buyer Should Know

EU ETS and FuelEU Maritime are transforming bunker economics on European voyages. The essentials of both regimes and how they interact with bunker decisions.

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