What is a CAS registry number?

The CAS registry number, also known as a CASRN or simply CAS number, identifies a wide variety of chemical substances with a sequence of random digits. Created by the Chemical Abstracts Service, this unique number can have up to ten digits. There are up to 1 billion number sequences that can be chosen to label chemical substances, which means there’s plenty of room to grow. Currently there are over 182 million CAS registration numbers that have been assigned to a chemical substance. An astounding amount for sure!

Believe it or not, but there are thousands upon thousands of chemical substances used on a daily basis in the industrial world. Giving your employees the knowledge that allows them to protect themselves and others, apply any special training, and support their own successful performance involves CAS registry numbers. Not only that but 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 around hazardous chemicals. All of which is why this type of identification system is so integral to everyone’s safety.

Where are CASRN Numbers Found?

CAS registry numbers can be found on just about every GHS warning label in a facility, that number then leads the one reading the label to the appropriate SDS for further information on that specific chemical substance. While these labels may seem cramped with information, every bit of it is essential for determining the immediate dangers that a hazardous chemical poses to those working around it.

Overall, CAS identification numbers are an essential part of workplace safety when it comes to recognizing danger and preventing accidents from happening. There are also resources such as the CAS Common Chemistry site that allows the user to look up specific CAS registry numbers.


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