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National Institute of Standards & Technology Certificate of Analysis
Standard Reference Material® 2453a Hydrogen in Titanium Alloy
(Nominal Mass Fraction 125 mg/kg H)
This Standard Reference Material (SRM) is intended primarily for use in evaluating chemical and instrumental methods for determination of hydrogen in titanium alloys. A unit of SRM 2453a consists of one bottle containing 10 g of pins having an approximate mass per pin of 0.10 g and approximate dimensions of 2.5 mm diameter and 4.5 mm length.
Certified Mass Fraction Value: A certified mass fraction value for hydrogen in SRM 2453a is provided in Table 1 . A NIST-certified value is a value for which NIST has the highest confidence in its accuracy, in that all known or suspected sources of bias have been investigated or taken into account. A certified value is the present best estimate of the true value based on the results of analyses performed at NIST and collaborating laboratories. Value assignment categories are based on the definitions of terms and modes used at NIST for certification of chemical reference materials.