As it absorbs moisture, orange silica gel turns green, indicating that it needs to be activated again or replaced. prevents mold, condensation, and rust from growing in enclosed spaces. Orange-colored silica gel is ideal for applications requiring visual moisture control. As it absorbs moisture, the silica gel will turn green or orange, indicating that it needs to be reactivated or replaced. By adsorbing and trapping moisture from the air, silica gel lowers humidity and prevents mold, condensation, and rust from growing in enclosed spaces.