Wednesday, January 25, 2012

NIST Certification: Questions for Q-Bot

Dear Q-Bot:
Can you tell me a little about NIST Certification? I think it's some sort of standard. Thanks!
— A.D. via the Internet


Hello A.D.:

NISTNIST stands for the National Institute of Standards and Technology, which is an agency of the United States Department of Commerce. Founded in 1901, the agency was the U.S.'s first federal physical science research lab. The NIST was founded with the purpose of furthering measurement science, standards, and technology as to promote economic security and U.S. innovation, enhance industrial competitiveness, and elevate our quality of life.

The NIST creates a Standard Reference Material® (SRM) to be used to certify and confirm the accuracy of specific measurements. The SRM is used for instrument calibration and to promote the creation of new methods of measurement. An SRM is also used to perpetuate measurement traceability in the U.S. When an SRM is created the NIST also provides a Certificate of Analysis and a Material Safety Data Sheet (MSDS), if applicable. These SRMs are the basis for the way products are tested to gain NIST Certification.

In addition to the SRM, there are a few other common terms you might come across when researching NIST Certification: NIST SRM Certificate or Certificate of Analysis, NIST Certificate of Traceability, NIST Traceable Reference MaterialTM, and NIST Certified Value are a few. According to the NIST, these are defined as:
  • NIST Standard Reference Material (SRM) - A Certified Reference Material (CRM) issued by NIST that also meets additional NIST-specific certification criteria and is issued with a certificate or certificate of analysis that reports the results of its characterizations and provides information regarding the appropriate use(s) of the material (NIST SP 260-136).
  • NIST SRM Certificate or Certificate of Analysis - In accordance with ISO Guide 31: 2000, a NIST SRM certificate is a document containing the name, description, and intended purpose of the material, the logo of the U.S. Department of Commerce, the name of NIST as a certifying body, instructions for proper use and storage of the material, certified property value(s) with associated uncertainty(ies), method(s) used to obtain property values, the period of validity, if appropriate, and any other technical information deemed necessary for its proper use.
  • NIST Traceable Reference MaterialTM (NTRMTM) - A commercially-produced reference material with a well-defined traceability linkage to existing NIST standards for chemical measurements. This traceability linkage is established via criteria and protocols defined by NIST to meet the needs of the metrological community to be served (NIST SP 260-136). A NIST NTRM may be recognized by a regulatory authority as being equivalent to a CRM.
  • NIST Certificate of Traceability - Document stating the purpose, protocols, and measurement pathways that support claims by an NTRM to specific NIST standards or stated references. No NIST certified values are provided, but rather the document references a specific NIST report of analysis, bears the logo of the U.S. Department of Commerce, the name of NIST as a certifying body, and the name and title of the NIST officer authorized to accept responsibility for its contents.
  • NIST Certified Value - A value reported on an SRM certificate or certificate of analysis for which NIST has the highest confidence in its accuracy in that all known or suspected sources of bias have been fully investigated or accounted for by NIST. (NIST SP 260-136)
Keeping all that in mind, the simplest way to define the NIST Certification process is that a product gets tested against an SRM to see if it meets the specific criteria for that product type. Most products that measure something, such as clocks, thermometers, tachometers, light meters, etc., have an NIST SRM for the manufacturer to make a comparison with. When a product is certified by the NIST it can be sold with an NIST Certificate.

NIST Certification testing can also result in an NIST Certificate of Calibration, NIST Certificate of Compliance, or NIST Certificate of Traceability. A Certificate of Calibration means that the product was tested and approved to meet a certain level of accuracy. The Certificate of Compliance is similar to the Certificate of Calibration, but in this case the product fell within a stated tolerance but can not be adjusted. The Certificate of Traceability is given to a product that was not tested against an NIST SRM, but instead compared to an NIST SRM of a similar product. The Certificate of Traceability is awarded then after the product comparison has been made and the proper paperwork filled out.

It is important to note that an NIST Certified product is not endorsed or recommended by the NIST. And while the process of getting a product certified and selling it may seem more costly than non-certified products, the NIST product is guaranteed to be accurate through the specially designed tests created to ensure measurement quality and precision-made products.


FOR FURTHER REFERENCE:

National Institute of Standards and Technology Web Site
NIST Overview Video
NIST's Standard Reference Materials Page
NIST on Twitter
NIST Designed and Operated Atomic Clock
Wikipedia's NIST Page

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