Separate Source Standards

We offer dozens of Separate Source stock standards , with many more available through our custom standards program. Separate Source standards are pairs of Supelco brand products having identical composition that are prepared from independently sourced raw materials and are independently quality controlled. Our internal processes prevent the use of the same raw material lot for both the primary and secondary standards. This can be verified by comparing the raw material lot numbers on the Certificate of Analysis accompanying each standard in the pair. As an additional service, Separate Source standards contain a specific note at the bottom of each COA denoting this as a SS material. This note addresses the requirements of both internal and external auditors, particularly in the environmental commercial testing market.

If you are unable to locate a Separate Source standard for your application, please send an e-mail to We’ll be happy to assist you.