Redi-Dri™ Packaging System Test Protocol and FAQs

A time study was performed on the product material to test the Red-Dri Packaging System against standard packaging. Equivalent units of both packaging systems containing potassium chloride (KCl) were introduced to a controlled environment with 85+/-5% relative humidity. Material was visually inspected and tested on a monthly basis by Loss on Drying (LOD). LOD analysis was performed on representative 5g samples at 130 ºC for four hours under full vacuum.

Results indicated:

  • The traditional packaging allowed the product material to absorb atmospheric moisture resulting in a hard clumpy appearance and a higher LOD value.
  • The Redi-Dri packaging prevented water absorption and LOD values confirm a decrease in moisture content.  The Redi-Dri powder remained free-flowing through the 9-months of testing.


The graph illustrated above demonstrates the long-term benefit of the exclusive Redi-Dri packaging system.

The graph illustrated above demonstrates the long-term benefit of the exclusive Redi-Dri packaging system.

The samples from the traditional packaging continued to absorb water from the atmosphere which caused hard chunks to form as shown by increasing LOD values. The LOD results for the Redi-Dri solids trended in the opposite direction of the traditional packaging and actually showed decreasing H2O content. The appearance of the Redi-Dri powder therefore remained free flowing throughout the 9 month study. These results confirm the new Redi-Dri packaging system provides a superior barrier against the absorption of water from the atmosphere.

Prevent hygroscopic powders from absorbing moisture and never deal with solid clumps again.

Frequently Asked Questions for Redi-Dri Products

  • What are the Redi-Dri unit sizes?

    The Redi-Dri product line is available in sizes from 100 grams up to 25 Kg. Product sizes are determined based on customer suggestion, product attributes, and evaluation by the Redi-Dri innovation team. Each product and unit size is researched for feasibility and approved prior to release to our customers, so if you don’t see the right size today, be sure to check back in the near future. If you have a specific need, please forward inquiries to your sales representative or the lab essentials inbox at

  • Are smaller or larger Redi-Dri unit sizes available?

    Redi-Dri is a superior product that requires specialized processes and innovative packaging. Therefore, there is additional cost to each unit. For that reason, Redi-Dri is often limited to a minimum size of 100G or 500G. Given the benefits of the product, Sigma-Aldrich believes that units smaller than this size generally do not receive enough benefit to make the additional cost to Sigma-Aldrich and the customer worthwhile. For large-scale, Redi-Dri is available in unit sizes up to 25Kg and expanding daily. If you don’t see it today, you may see it soon. Typical unit sizes include 100G, 500G, 1KG, 2.5KG, 12KG, and 25KG.

  • Can I order Redi-Dri in a "custom size" to meet my needs?

    Redi-Dri materials are researched for feasibility with the packaging system at the given prepack sizes. The research is time consuming and provides in-depth analysis to ensure the process will deliver the consistent form that you expect. Therefore, if possible, we generally suggest utilizing the pre-pack sizes. However, for special considerations, Sigma-Aldrich will evaluate the feasibility of utilizing the Redi-Dri packaging system for a specific need. Please forward inquiries to your sales representative or the lab essentials inbox at

  • I have a specific product that hardens or clumps, how can I make a suggestion for an addition to the Redi-Dri product line?

    The Redi-Dri product line is based on customer need and Sigma-Aldrich is willing to evaluate products for successful transition to the Redi-Dri packaging system. Please forward inquiries to your sales representative or the lab essentials inbox at Please note that all products do NOT work well with the Redi-Dri packaging system, so at times, certain products cannot be utilized with this system.

  • How does the Redi-Dri packaging system affect the quality specifications of my product?

    Simply, the Redi-Dri packaging system does NOT negatively affect the quality specification guarantee of any Sigma-Aldrich product. Redi-Dri product does not contain chemical additives, anti-clumping agents, or hydrophobic compounds.

    The Redi-Dri innovation team tested the quality specifications of material in the Redi-Dri packaging system against material stored in normal packaging. In all test cases, the Redi-Dri material was stored in a controlled environment with high humidity (85+/-5%) for over 18-months. Upon testing after the 18-months of storage, all products were tested against quality specifications and continued to meet their respective specifications.

    Additionally, Redi-Dri materials were tested for solubility and trace metal content by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). When compared to control samples, no notable or unexpected differences were noted. Overall, the product quality specifications you expect are not affected by the Redi-Dri packaging system.

  • I have a question about the Redi-Dri product line. Who can I ask?

    Please forward inquiries to your sales representative or email us at