Batch numbering

A batch is a quantity of material produced in a single defined operation and expected to be homogeneous within itself. The batch number is the identifier under which every record about that quantity is filed: synthesis conditions, analytical results, storage history and distribution.

Its value comes entirely from consistency of use. A number that appears on the certificate but not on the container, or that changes format between systems, breaks the link it exists to preserve.

What a workable system provides

• A unique identifier that is never reused, printed on the container itself rather than only on outer packaging.
• A one-to-one link between the identifier and a complete set of records.
• A retained sample from each batch, so later questions can be tested rather than argued.
• A recorded manufacture date and, where applicable, a retest or expiry date derived from stability data rather than from convention.
• A defined route by which a batch can be traced forwards to everyone who received it, which is what makes withdrawal possible.