Desiccants according to DIN 55473

What DIN 55473 desiccant variants are available?

ThoMar DIN 55473 desiccant bags are available in two different versions – with low-dust and dust-proof casing material. Low-dust (Type A) and dust-proof (Type B) casing materials differ in the density of the bag material and the amount of dust that can penetrate through this material.

CertiDry Type A desiccant bags according to DIN 55473 are available in the following bag sizes:

4 DU, 8 DU, 16 DU, and 32 DU

CertiDry Type B desiccant bags according to DIN 55473 are available in the following bag sizes:

1/6 DU, 1/3 DU, 1/2 DU, 1 DU, 2 DU, 4 DU, 8 DU, 16 DU, and 32 DU

Where and how are DIN 55473 desiccants used?

Desiccants according to industrial standard DIN 55473 are primarily used in the export sector, e.g., by specialized export packers. The desiccant bags are placed or hung directly into the packaging of goods to be transported or stored. It is important to note that the packaged goods and the desiccant must be sealed from the external climate using a barrier film (in-box desiccant).
DIN 55473 desiccant bags are particularly well-suited to protect sensitive goods from moisture during extended storage and transport. When used correctly, they prevent mold infestation, corrosion, and other moisture damage. They are ideal for protecting, for example, electronic devices, machine parts, leather goods, chemical products, and pharmaceutical preparations from excessive humidity within the transport packaging.

Mechanism of action of dry clay as a desiccant

Desiccant bags conforming to DIN 55473 contain a dry clay which, due to its properties, can quickly and lastingly adsorb and store water vapor from the air. The basis for measuring these desiccant bags is desiccant units (DU). One desiccant unit is the amount of desiccant that adsorbs at least 6.0 g of water vapor in equilibrium with air at 23 °C (± 2 °C) and 40% relative humidity.
As dry clay is a mineral raw material, the exact composition, contained quantity, and weight of the bags may vary. However, these desiccants, which meet the industrial requirements of DIN 55473 and the technical conditions of the American military standard MIL-D-3464E, have the advantage of being almost identical in quality and size regardless of the manufacturer.

What does low-dust / dust-proof casing material mean?

The casing material of CertiDry Type A desiccant bags according to DIN 55473 consists of a textile fabric of individual fibers with high water vapor permeability. It is referred to as low-dust because only a few dust particles are generated by the abrasion of the beads, which can then pass through the outer material. According to DIN 55473, low-dust means that a maximum of 10 mg of dust per desiccant unit may escape from the casing material.
The casing material of CertiDry Type B desiccant bags is made of a dust-proof material. According to DIN 55473, for dust-proof materials, a maximum of 1 mg of dust may escape from the casing material, regardless of the number of desiccant units. The membrane of these casing materials has such a high density that almost nothing can escape from it. Tyvek®, for example, is suitable as such a material, consisting of an endless fiber. The absence of fiber ends in the material results in less abrasion, which means less dust is generated. It is also considered extremely tear-resistant, moisture-resistant, and dense. These properties ensure that the desiccant bag can absorb moisture over a longer period.