A lab desiccator is a sealable container used in a laboratory to create and maintain an atmosphere of low humidity. Its primary function is to protect moisture-sensitive items (hygroscopic chemicals, dried samples, biological specimens, etc.) from ambient moisture and dust. The desiccator works by containing a drying agent, called a desiccant (such as silica gel, anhydrous calcium chloride, or molecular sieves), in its lower compartment. This desiccant absorbs water vapor from the air inside the sealed container, maintaining a very dry environment.