Radiation processing is carried out under fixed path conditions where (a) a process load is automatically moved through the radiation field by mechanical means or (b) a process load is irradiated statically by manually placing product at predetermined positions before the process is started. In both cases the process is controlled in such a manner that the process load position(s) and orientation(s) are reproducible within specified limits.

Some radiation processing facilities that utilize a fixed conveyor path for routine processing may also characterize a region within the radiation field for static radiation processing, sometimes referred to as "Off Carrier" processing.

Radiation processing may require a minimum absorbed dose (to achieve a desired effect or to fulfill a legal requirement), and a maximum dose that can be tolerated (while the product, material or substance still meets functional specifications or to fulfill a legal requirement).

Dose mapping is used to characterize the radiation process and assess the reproducibility of absorbed-dose results, which may be used as part of operational qualification and performance qualification.

Dose mapping is used to determine the spatial distribution of absorbed doses and the zone(s) of maximum and minimum absorbed doses throughout a process load, which may consist of an actual or simulated product.

Dose mapping is used to establish the relationship between the dose at a reference position and the dose within the minimum and maximum dose zones established for a process load.

Dose mapping is used to verify mathematical dose calculation methods. See Guide E 2232.

Dose mapping is used to determine the process shutdown and startup transit dose effect on the distribution of absorbed dose and the magnitude of the minimum and maximum doses.

Dose mapping is used to assess the impact on the distribution of absorbed dose and the magnitude of the minimum and maximum doses resulting from the transition from one process load to another where changes, for example, in density or product loading pattern may occur.