Most disappointing biomass shipments do not fail because the supplier was dishonest. They fail because the buyer evaluated a sample and the supplier could not repeat it. Sampling tells you what one lot looked like on one day. Repeatability is a property of the operation, and it has to be assessed separately.
Start with the production method, not the sample
Ask how the material is produced, dried and screened before you ask for a sample. A supplier who sun-dries on open ground will have a moisture profile that swings with the season. A supplier with mechanical drying will not. Neither is disqualifying, but they carry different risk, and the difference should be priced rather than discovered on arrival.
Ask what happens to material that fails
This question is more revealing than any certificate. A supplier with a real process can describe where off-spec material goes and who decides. A supplier without one will usually answer in generalities, which tells you the specification is aspirational rather than operational.
The practical checklist
- Production method, drying method and screening arrangement
- Whether the sample was drawn from the lot being offered or from a separate batch
- Storage conditions between production and loading
- Who performs pre-shipment checks and what is recorded
- References from prior counterparties, ideally in your own market
- Whether the supplier has issued the document set your destination requires before
A trial container against an approved sample is cheaper than an unusable full shipment. Buyers who insist on one before committing to a schedule generally have fewer disputes.
Seasonality is a specification issue
In Indonesia the rainy season materially affects the moisture content of open-stored biomass. If a moisture ceiling is agreed in the dry season and the schedule runs into the wet season, either the price or the ceiling needs to move. Agreeing tolerance bands up front avoids a renegotiation at the worst possible moment.
This note is general guidance for buyers, not legal, tariff or financial advice. Requirements vary by destination and by commodity — confirm your own position with your customs broker and advisers.