The VDI (Verein Deutscher Ingenieure) published the standard 2083, part 2 final in April until then only available as draft. In principle, this standard summarises the requirements on clean rooms according to VDI 2083 part 1and 3 as well as DIN EN ISO 14644-1 and -3 together and indicates the time intervals at which compliance with the requirements should be checked. What is meant by this are the measurements from the first qualification (OQ) that have to be repeated periodically. These include among others the determination of the airflow velocity, the volume flow rate and air change rate of rooms, filter leak tests, determination of filter pressure differential and pressure difference between rooms, air cleanliness classification as well as other tests such as noise level and illuminance.
The VDI standard 2083 part 2 can be bought at the publishing house Beuth Verlag in German and English language.