One of the most common technical questions is "how much silica gel do I need?". The answer depends on several factors, and the right choice affects both the effectiveness of the protection and the cost. This guide walks through the elements that determine sizing and packaging.
For a quick estimate, try the silica gel sizing calculator — you enter the volume, packaging, duration and climate, and the tool estimates the number of units and the gram weight needed, including for shipping containers.
The factors that determine the quantity
Sizing starts from a set of parameters that should be agreed with the supplier:
- Total quantity — the first factor; the order volume also determines the applicable price level.
- Volume to be protected — a small package needs a single sachet, while a shipping container needs high-capacity bags.
- Relative humidity of the environment — the more humid the environment, the more desiccant is needed.
- Protection duration — long transport or storage periods call for a larger capacity reserve.
Granulation
The granule size is chosen according to the application. The standard granulations are:
| Granulation | Characteristics |
|---|---|
| 1–2 mm | Fast adsorption, ideal for small volumes and sachets |
| 2–6.3 mm | Balance between speed and airflow, general use |
| 6.3–11.2 mm | Good airflow, suitable for large volumes |
| 2–4 mm (beaded) | Spherical shape, preferred in filters and desiccators |
Residual moisture of the silica gel
In its active (anhydrous) state, silica gel has a residual moisture content below 5% by weight. This is not a product variant, but a characteristic of the dry, ready-to-use material.
The lower the residual water content, the more free adsorption capacity remains. The usual threshold of below 5% (in line with MIL-D-3464E requirements) ensures balanced and predictable adsorption behaviour for most applications.
Packaging type
The packaging is chosen according to the usage environment and the mechanical stress:
| Packaging | Weights | Typical applications |
|---|---|---|
| Perforated PP sachet | 2–50 g | Shoe boxes, electronics, metal parts |
| Non-woven (TNT) bag | 100–1000 g | Automotive, electrical cabinets, shipping containers |
| Jar | 1500 g | Transformers, laboratories, desiccators |
Products can be packaged on request in quantities from 2 g up to 50 kg, with the packaging material affecting the final price.
Special orders
For requirements outside the standard specifications — hygroscopicity, pH value, exceptional mechanical strength — each order is reviewed individually by the technical team. Delivery and payment terms are also set individually.
The shelf life is 12 months, provided the transport, storage and handling rules are followed. Keep in the original packaging, in an environment with humidity below 30% and temperature above 10°C.