Breakage

What It Measures

Breakage — also described as mechanical durability, shatter resistance or fines generation — describes how much of a consignment breaks into smaller pieces or dust under handling and transit. It is expressed either as a durability percentage (mass surviving a defined stress) or as a fines fraction (mass passing a stated sieve).

For compressed cube or briquette charcoal it captures whether pieces stay intact from factory to bowl; for lump charcoal it captures the production of dust and undersized fragments.

Why It Matters

Breakage costs money twice: broken pieces and fines are hard to sell at full price, and dust is a complaint and a handling hazard. A product that arrives largely intact protects margin and customer experience.

Breakage also interacts with size grading — a load that breaks in transit no longer matches the declared size distribution, so breakage and size tolerance are read together.

Typical Measurement Method

Mechanical durability is assessed by subjecting a known mass of material to a defined stress and measuring what survives. Tumbling methods (such as the ISO 17831-1 durability drum) rotate a sample and then weigh the intact fraction; drop tests (such as the ASTM D440 drop shatter for coal) drop a sample a defined number of times and measure the surviving coarse fraction.

Fines are determined by sieving a sample and reporting the mass passing a stated sieve size. The method, the stress applied, and the sieve cut must all be stated for a result to be meaningful.

Buyer Relevance

Buyers who ship in bulk or who repack should specify a maximum fines fraction or a minimum durability figure and agree the test method, because breakage is strongly influenced by packaging and handling, not just the product.

Because breakage develops in transit, a factory durability figure may not describe the load as delivered; an arrival inspection on the landed consignment is the more commercially meaningful check.

Limitations

Breakage is sensitive to the stress conditions of the test and to packaging and handling, so results are comparable only under matched methods. A durability drum and a drop test measure different things and produce different numbers.

No single durability figure predicts arrival condition across all logistics routes. This page describes methodology only and publishes no breakage figures.

Data Source

Public standard methodology (general); not supplier-specific test data.

Last updated: 2026-10-07

Public methods commonly referenced

• ISO 17831-1 — Solid biofuels: determination of mechanical durability of pellets and briquettes
• ASTM D440 — Drop shatter test for coal
• Sieve-based fines determination (fraction below a stated size)

Standard references are given as general, publicly documented method families. Applicability, current edition and reporting basis must be confirmed with the testing laboratory for any specific report.