Expiry explained
AccuStandard has put together an explanation of CRM expiry and how their approach provides great benefits to laboratories using reference standards and CRMs manufactured by AccuStandard.  Please see the video and transcript below.

Transcript

Understanding Reference Standard Expiration

Based on over 30 years of stability data and extensive knowledge of chemical behavior, AccuStandard's analytical chemists assign an expiration period ranging from three months to ten years. 

Certain chemicals, due to their nature, are more likely to degrade than others. Conditions that may cause degradation include: time, temperature, solvent, air, light, pH, and other analytes present.

Our on-going stability program is constantly retesting standards to see if the expiration period can be extended. If you have an unopened, expired standard contact us to see if the expiration date of your AccuStandard product can be extended. Some formulations are inherently unstable, so some products have a short expiration period to reflect their anticipated usable shelf life.

For example, our Method 8260 Additions Standard has a four-month shelf life. 

Here is what a good chromatogram looks like for this standard and here is a chromatogram of the same product several months later after improper storage.

The integrity of the standard is affected and ketals have formed due to both improper storage and time. As an every day example leaving milk out on your kitchen counter will cause it to prematurely expire before the provided expiration date. Milk must be sealed and refrigerated for the expiration date to remain valid: the same principle applies to properly storing your standards. Proper storage of your standard is essential to ensure the optimal stability of the analytes.

Some products are shipped in a cold pack to delay their exposure to higher temperatures.

AccuStandard states the storage conditions on the labeland the certificate of analysis.

For more information, contact Novachem, your local distributor.​