Gilson stocks Standard Reference Materials (SRMs) issued by the US National Institute of Standards and Technology (NIST) for assessment of sieves and other instruments.
SRMs are used on sieves in the same manner that tests would be performed, and a percentage of retained material is calculated for each sieve. Effective openings are determined from calibration data on the supplied NIST Certificate. SRMs do not take the place of Verification Services, but are an economical way to monitor performance while allowing sieves to remain in service.
Each NIST Glass Bead sample measures effective sieve openings for a narrow range of sieves. NIST Sand also determines effective openings, but for a wider range of sieves. The BS-42 Sand set includes three 150g bottles with progressive sizes covering a total range from No.30 to No.325 (600 to 45µm). Portland Cement No.114 consists of twenty sealed pouches, and is required by ASTM and AASHTO standards for calibration of Cement Fineness sieves, Wagner Turbidimeters, and Blaine Air Permeability Apparatus.