The primary feature of the revised standard created, among other minor revisions, three grades of test sieves: Compliance grade (WST equivalent standard sieve); Inspection grade (WST equivalent certified sieve); and Calibration grade (WST new equivalent certification-PLUS).
The grade levels are determined by the level of examination of the sieve cloth used in a test sieve. All three products offer some level of traceability to NIST, when examined per the standard. The new Calibration grade, when examined, per the revised standard, offers a 99.73% level of confidence. The complete ASTM E11-09 standard provides all the details regarding the calculations used to insure that confidence level and other formulas used in the preparation of the revision.
W.S. Tyler is now offering “Certification-PLUS” examinations to meet the ASTM calibration sieve requirements for new and in-use test sieves. W.S. Tyler’s on-site laboratory performs more than 8000 examinations per year, with an automatic, non-contact, dimensional measurement system that is traceable to NIST.
For more information, visit www.wstyler.com.