The gold ducts deliver air to filters and fans that cover the entire ceiling of the rooms below.
These HEPA filters pass less than 1 particle (larger than 1 micron) per cubic meter of air. This "Class 1" air is more than 100,000 times cleaner than the air of a hospital's surgical cleanroom.
Extreme cleanliness is required because the transistor switches of an integrated circuit (IC) can be less than 0.1 microns in size. A single dust particle can thus disrupt the fabrication of many transistors, causing the entire chip to fail.