In many instances, food containers are loaded directly into carriers immediately after final packaging. This situation makes stationary lot sampling and inspection impractical. For such circumstances, the optional procedure for on-line sampling and inspection using cumulative sum sampling plans is provided. On-line sampling and inspection is a procedure in which subgroups of sampling units are selected randomly from predesignated portions of production. The acceptability of the portions of production is determined by inspecting, at the time of the sampling, the subgroups which represent these portions. On-line sampling and inspection contrasts with stationary lot procedures in which sample units are selected randomly and inspected and lot acceptability determinations are made only after lot production is completed.

On-line sampling and inspection procedures may be instituted only when all of the following conditions are met:

When authorized by the Administrator and acceptable to the user and producer, if different from the user.

When inspection is origin inspection (see § 42.102).

When previous production lots from the producer are currently on, or eligible to be on, either normal or reduced inspection. (When shifting from stationary lot sampling and inspection to on-line sampling and inspection, normal on-line inspection shall be initially used.)

When inspection of the containers is performed at a point after which all condition of container related characteristics are fixed and will not be subject to change during final handling.