As you know, the clean room whose level is  Class 10 is made of FFU (fan filter unit),access floor,dry coil and their control system included temperature,humidity ,differential pressure and particle.There must be one or more OAC(out air conditioner) or MAU(make-up air unit)set in this system to keep the differential pressure between clean room and outside of clean room.There was a clean room,Class 10,1500m²,constructed in our company last year.And now the production facilities are being installed in it.