How to Control Humidity in Clean Rooms

A clean room is a highly controlled environment in which products are manufactured. Everything from electronics and cosmetics to biopharmaceuticals requires a properly functioning clean room for safe and successful product completion. Different products have their own relative humidity (RH) requirements, but generally the humidity should be maintained between 35 and 65 percent at a temperature below 70 degrees Fahrenheit. Several devices can keep the humidity in check.

Things You'll Need

• Air conditioner
• Dessicant
• Air scrubber

Show More

Instructions

• 1

  Install an air conditioning system. Air conditioning lowers the temperature of a surface exposed to the clean room airstream below the dew point of that airstream, preventing condensation on exposed surfaces. Excess water vapor is condensed and removed, resulting in dehumidified air.

• 2

  Install an air dessicant. A dessicant medium dries out the air. Air passes through it and the medium absorbs moisture directly from the air. The dehumidified air is rerouted to the clean room. Dessicant dehumidifiers produce dew points below zero degrees Fahrenheit.

• 3

  Install an air scrubber. Air scrubbers are especially useful in clean rooms where the manufacturing process of the product produces a liquid waste such as grease or vapor. Liquid waste can raise the humidity in a clean room. Higher humidity levels result in greater risk of contamination, less control over chemical reactions and the risk of static electricity. An air scrubber neutralizes and removes these effluents.

• 4

  Control the human element. Clean rooms are classified: Class 100, Class 1,000 and Class 10,000. The class refers to the number of particles allowed per cubic foot of air. A Class 100 clean room does not allow more than 0.5 microns per cubic foot, which is 200 times smaller than a single human hair. Coast Wide Labs reports that a motionless human being releases up to 100,000 particles per minute. Consider the impact of several human beings in motion and the release of skin cells, sweat droplets, cosmetic particles and the like. The more humans move and the more they bring with them into the clean room, the greater the potential for risk of contamination and the harder air purification systems have to work.