We all know about space temperature but when it comes humidity not many have a grasp of the subject. This engineering white paper (EWP-7.b) is a supplement to the humidity basics engineering white paper EWP7. While the previous white paper focused on preventing dry conditions by maintaining relative humidity generally ≥40%rh, this white paper focuses on preventing humid conditions. We used dehumidification equipment (removal of moisture from the air) to maintain relative humidity generally ≤60%rh. But before we dive into dehumidifying let’s do a quick review on humidity in general.