Moisture Sensitive Devices (MSD) refer to electronic components that are sensitive to moisture.
Moisture, also known as humidity, refers to the amount of water vapor in the atmosphere that the components are exposed to. The environment is typically the factory floor or production line, as well as any environment the components are exposed to after being removed from vacuum-sealed packaging.
Please note that liquid or solid water cannot be counted as part of humidity! In fact, the human body can feel humidity. In a high humidity environment, you can feel that sticky sensation, like when it’s about to rain but hasn’t started yet, and your whole body feels damp.