Why Clean Room Humidity Standards Matter

Formerly reserved for the medical, pharmaceutical, and micro-electronics industries, clean rooms have become more widespread and prevalent across the world as the tech industry has continued to boom, and regulations have constricted their grasp on more quality control departments.

Clean rooms are monitored and controlled for seemingly every environmental condition, but one that is very, very relevant, to both the micro-electronic tech corporations and the medical and pharmaceutical industries is . . .


Controlling the humidity of a clean room is important to companies not because of a single problem that extreme high or low humidity causes, but rather because of its influence on many factors that could degrade a clean room’s environment, and thus its certification on the ISO class scale.

Those factors include the following:

1. Static Charge

You’d think that low levels of humidity would be the preferred option every time, but static electricity shows that a happy medium is ideal. When humidity levels in an environment get to low, static electricity builds up.

2. Metal Corrosion

While some metals (like aluminum) form a protective oxide on their surface, blocking degrading corrosion caused by high humidity, other metals (like copper oxides) do not. If your clean room is dealing with metals, be sure to keep your humidity under that 60% threshold.

3. Condensation

The conversion of water from a gas state to a liquid state is bad news for your clean room. The effect of Kelvin condensation specifically, becomes very problematic when humidity reaches the 70% threshold.

4. Personnel Comfort

The last thing your personnel, with their E.T. like contamination suits and astronaut-looking helmets on want to be is hot and sticky. Keep humidity levels low enough as to not make them uncomfortable.

5. Bacterial Growth

Bacteria and mold like moisture. Once your clean room climbs above the 60% Relative Humidity threshold, bacteria, viruses, fungi, and more will start to multiply. Very literally, your clean room will cease being clean.