Cleanrooms and equipment

In downflow cleanrooms, why are perforated floor panels (gratings) used?

  1. ATo make the floor non-slip
  2. BTo make the floor lighter
  3. CTo pass air blown from the ceiling into the space below the floor for recirculation
Show answer and explanation

Answer: C. To pass air blown from the ceiling into the space below the floor for recirculation

In the downflow method, air blown from ceiling filters is drawn through the perforated floor into the underfloor space, then returns to the ceiling through side passages and the like to recirculate. Because the air flows in one direction, generated particles are carried below the floor immediately.

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More Cleanrooms and equipment questions

  1. For process equipment using vacuum, which device treats exhaust gas containing harmful substances produced by reactions, tool by tool?
  2. Which equipment is installed in semiconductor fabs to prevent loss of wafers in process due to voltage sags or power outages?
  3. Which ISO 14644-1 cleanliness class corresponds to Class 100 of the former US federal standard (no more than 100 particles of 0.5 µm or larger per cubic foot)?
  4. What is a typical guideline for the air velocity blown from the ceiling in downflow cleanrooms?
  5. In bay-and-chase cleanrooms, how is the cleanliness of the maintenance space behind equipment (the chase) typically handled?