Concession Volume

Concession volume commonly refers to the quantity of material, parts, assemblies, or finished units covered by an approved concession. In manufacturing and quality contexts, a concession is a documented acceptance of a specified nonconformance under defined conditions, and the concession volume sets the numerical scope of that acceptance.

This term helps define boundaries. It indicates how many affected items may be shipped, used, processed, or accepted under the concession. It does not, by itself, describe the technical deviation, the reason for acceptance, or the disposition decision criteria. Those details are usually recorded elsewhere in the concession or related quality records.

How it is used in operations

In practice, concession volume may appear as a count of pieces, batches, serial-numbered units, lots, or another controlled quantity measure. The exact unit depends on how the product is identified and controlled in the organization.

• For discrete manufacturing, it may be the number of parts or assemblies covered.

• For lot-controlled material, it may be a lot, batch, or a defined subset of that lot.

• For serialized products, it may refer to specific serial numbers rather than a general count.

Systems such as QMS, MES, or ERP may reference concession volume when tracking nonconforming product, release decisions, genealogy, and downstream use restrictions.

What it includes and excludes

Concession volume includes only the quantity explicitly authorized by the approved concession. It does not automatically extend to future production, similar parts, or additional nonconforming units unless those are also documented and approved.

It also should not be confused with broader production volume, shipment volume, rework volume, or scrap volume. The term is limited to the quantity within the approved scope of concession treatment.

Common confusion

Concession volume is often confused with concession rate or concession frequency. Concession volume is the amount of product covered by a specific concession, while concession rate refers to how often concessions occur or what share of output they represent.

It can also be confused with deviation quantity. In some organizations the terms are used similarly, but a deviation often refers to permission before manufacture or processing, while a concession commonly refers to acceptance of a known nonconformance after it exists. Usage varies by company and industry.

Example

If 25 parts in a lot have a minor documented nonconformance and quality approval allows those 25 specific parts to be accepted for use, the concession volume is 25 parts, not the full lot unless the full lot is explicitly included.