CAS Number

CAS Number

A CAS number, also known as a CASRN number, is a route for identification of specific chemical substances. This number can contain up to ten digits and has three parts. The first section can hold between two and seven digits, the second section contains two digits, and the third only has one as a check. With this unique numbering system, there are up to 1 billion different combinations that can be utilized. Now, there is no significance to the number itself regarding the chemical’s structure or nature of the molecule, just that it is an unambiguous way to identify chemicals.

There are currently over 182 million organic and inorganic chemicals and substances that have a CAS number. On top of that, there are more than 68 million protein and DNA sequences that also have a CAS identification number.

Where exactly can these number be found? That’s easy, in the safety world, CAS registry numbers can be found on just about every warning label in a facility regarding GHS requirements. It can also be found in the Safety Data Sheet that must be present with every hazardous chemical within the building. That information will specifically be found in the hazardous ingredients section.

Lasty, why are these identification numbers needed? Well, knowing what kinds of dangerous chemicals or other dangerous substances are around your employees is a big concern for most employers, and rightly so. Complying with regulations put forth by both OSHA and ANSI mean that the employees must be given all the resources and information they need to keep themselves safe. And that includes being around hazardous chemicals. Not only that, but CAS numbers can be helpful for first responders when they arrive after an emergency situation involving those chemicals.

Overall, CAS identification numbers are an essential part of workplace safety when it comes to recognizing danger and preventing accidents from happening.


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