The grease will pick up dirt, preventing formation of a seal. Seals should be kept clean and well greased and the lid should always slide easily on or off. If a lid can be directly lifted off the desiccator, either the desiccator was not properly sealed or, more likely, it needs fresh lubricant. Rubber stoppers in the lid should always be pliable. Crucibles should not be packed excessively tight in a desiccator.
Air movement is necessary to cool crucibles.
Crucibles should not touch each other. The desiccator lid should be left open for minimal amount of time. Desiccant should be checked and dried periodically. Replace desiccant twice annually or more often depending on use. Use of desiccant with color indicator for moisture is recommended.