Desiccator Plate

Quick Answer: A desiccator plate is the flat, perforated plate that rests on the internal ledge of a laboratory desiccator, separating the drying agent below from the upper chamber and supporting crucibles, weighing bottles and dishes while they cool or are kept dry.

The Shelf Inside a Desiccator

A desiccator has two zones: the lower bowl, which holds a drying agent such as silica gel or anhydrous calcium chloride, and the upper chamber, where samples sit. The plate separates them. Its holes let water vapour pass down to the desiccant, while its flat surface keeps crucibles and bottles clear of the drying agent. Many plates have several larger holes sized to seat crucibles, so they stand upright rather than sliding about.

Plates of this kind are most often glazed porcelain, which is heavy enough to lie flat, easy to clean and tolerant of warm crucibles set on it after their first cooling. Plastic and perforated metal plates are also made. The plate must match the inside diameter of the desiccator at the ledge: one that is too small tips when loaded, and one too large will not seat. The listing does not state the diameter or material.

Replacement plates are needed when the original cracks or goes missing. The plate sits inside a laboratory glass desiccator or a vacuum desiccator, so measure the ledge diameter of yours before ordering.

Applications

• Cooling ignited crucibles before weighing in gravimetric analysis.
• Storing dried samples and primary standards away from humidity.
• Keeping hygroscopic reagents dry in weighing bottles.
• Replacing a cracked or lost plate in an existing desiccator.

Specifications

Care & Handling

• Let crucibles cool briefly on a heat-resistant tile before placing them on the plate.
• Wipe spilled desiccant dust off the plate so it does not contaminate samples.
• Wash and dry the plate completely before refitting; a wet plate adds moisture to the desiccator.
• Handle it by the edges, since porcelain plates chip if knocked against the desiccator wall.

Why Choose LabEquip

Analytical labs, pharmacy colleges and quality-control units that run gravimetric tests or store dried standards need desiccator plates, both with new desiccators and as spares. LabEquip lists this plate in General Lab Products; send the inner diameter of your desiccator at the ledge through the contact page.

Frequently Asked Questions

What is a desiccator plate for?

It forms the shelf inside a desiccator, holding crucibles and bottles above the drying agent. Its perforations let moisture from the upper chamber reach the desiccant below.

How do I know which size plate fits my desiccator?

Measure the inside diameter of the desiccator at the ledge where the plate rests. The plate should be slightly smaller, so it drops in easily but sits level on the ledge all round.

Why do some plates have large and small holes?

The small holes let vapour pass freely; the larger holes are sized to hold crucibles or small flasks upright so they do not slide or tip when the desiccator is moved.

Can a hot crucible be put straight onto the plate?

Let it cool for a minute or two on a heat-resistant tile first. A very hot crucible can crack the plate or the glass, and as the trapped air cools it creates a partial vacuum that makes the lid hard to open.

Which desiccant goes under the plate?

Silica gel with a colour indicator is common because it shows when it is exhausted and can be dried and reused. Anhydrous calcium chloride is a low-cost alternative, and phosphorus pentoxide is used where very strong drying is needed.

How should the plate be cleaned?

Take it out, brush off desiccant dust, wash it with detergent and water, rinse, and dry it thoroughly before refitting. Any remaining moisture would be taken up by the desiccant and shorten its life.

Last Updated: September 2026