Standard made in galvanized steel, inox or aluminium on request.
External insulation with heat-insulating adhesive polyethylene on first class of fire reaction (DM 26/06/1984).
Maximum operating temperature: 70°C.
PDM plenum are installed on multidirectional diffusers. The purpose of the plenum, or calm box, is that of delete or reduce the non-uniformity of the air speed profile, that come from the supply line. Thanks to that the diffuser launch characteristics will comply those provided.