Cleanrooms and equipment

How is the cleanliness of a cleanroom generally expressed?

  1. ABy the number of particles above a certain size in a given volume of air
  2. BBy the room's temperature and humidity
  3. CBy the brightness of the lighting
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Answer: A. By the number of particles above a certain size in a given volume of air

Cleanroom cleanliness is expressed by the number of particles above a certain size in a given volume of air. The international standard ISO 14644-1 classifies cleanrooms into Classes 1 to 9 based on particles per m³; the smaller the number, the cleaner. Temperature and humidity are also controlled, but they are not measures of cleanliness.

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More Cleanrooms and equipment questions

  1. What is the main reason yellow lighting is used in lithography areas?
  2. Which correctly describes a FOUP?
  3. What is the main purpose of the downflow method, in which air flows in one direction from ceiling to floor in a cleanroom?
  4. Which high-performance filters are used to remove fine particles from cleanroom air?
  5. What is the approach called that keeps only the small space around wafers at high cleanliness?