Only those products marked with an expiration date have an actual shelf life. In the case of unmarked items, there is no stated expiration date, and the shelf life is considered indefinite if stored and handled properly.

From a practical standpoint, the quality of some products may be affected by atmospheric contact. It is recommended that known hygroscopic or environmentally interactive materials be kept in sealed bottles.

In cases of atmospheric contact causing product degradation, it is often possible to detect physical changes such as liquefaction, color differences or physical variation which may be used as a guide to determine if a material has deteriorated.

EMD Chemicals recommends that the customer keep a list of the date of receipt and the date the product was first opened for use. Depending upon the nature of the product, review the appearance and quality on a regular basis. Decomposition data is available on the Material Safety Data Sheet which should be on file with the company. MSDS's are also available on the EMD Chemicals website (www.emdchemicals.com). Additionally, the customer may want to establish a protocol for replacement after a pre-determined time period. This could be part of the laboratory standard operating procedure (SOP).

EMD Chemicals appreciates your use of our products and looks forward to continued service for your laboratory needs. If you have any questions or need further assistance, in this matter or any other, please feel free to call 1-800-222-0342 or 1-856-423-6300.

Sincerely,

EMD Chemicals