In general, all incoming materials and finished products should be quarantined immediately after receipt for processing, until they are released for use or for distribution.

The manufacturer of starting materials normally specifies the storage conditions for raw materials. The manufacturer of the finished product must be aware of the storage conditions for the materials used in the factory, and must ensure that the materials are stored under appropriate conditions. Inspectors should check that the storage areas are maintained at the correct temperature and relative humidity specifications. The conditions should thus be controlled, monitored and recorded. Review the SOP and records for these parameters and ensure that the materials are stored in the correct environment by verifying the label information and environment control records

All containers of materials should be stored in an orderly way to prevent cross-contamination and mix-ups. Segregation between products is necessary to prevent possible cross-contamination. Segregation of different batches of the same product is also recommended to promote stock rotation.

Ensure that the manufacturer also has a system of controlling stock. Different systems exist for materials management, including a bin card system and bin locations, and computerized stock control. It is important to look at the process of issuing of material as well as the return of unused material back to the store.

During the inspection, also ensure that materials that have the shortest expiry date, are used first (First-in-first-out (FIFO) or EEFO (Earliest Expiry, First Out).