This document establishes a classification of filters based on their performance, as determined in accordance with ISO 29463‑3, ISO 29463‑4 and ISO 29463‑5. It also provides an overview of the test procedures and specifies general requirements for assessing and marking the filters, as well as for documenting the test results. It is intended to be used in conjunction with ISO 29463‑2, ISO 29463‑3, ISO 29463‑4 and ISO 29463‑5.