scope:

This standard is applicable to all ventilation and air-conditioning systems and units falling within the scope of VDI 6022 Part 1. It describes the hygiene requirements to be met by underground components, particularly in non-insulated outdoor-air intakes built for constructional reasons, and by ground heat exchangers.

A distinction must be made between direct and indirect ground heat exchangers. Indirect systems (with a heat transfer fluid) are not addressed by this standard. Furthermore, open direct systems in which air flows through beds of gravel or crushed rock, or between plates, are also excluded from the scope of this standard.

The standard includes information on the design and hygiene-compliant construction of underground air ducts, taking into account the protection goals specified in the series of standards VDI 6022.