Troemner Precision Analytical Masses (ASTM Class 4) is recognized by the National Institute of Standards and Technology (NIST), the American Society for Testing and Materials (ASTM) and the International Organization of Legal Metrology (OIML) for its precision weights and mass standards. The weights can range from the very precise, highly polished one and two-piece stainless steel weights to 5,000 lb cast-iron weights.
To maintain lab precision, it is necessary to perform routine calibrations and verifications using Troemner™ analytical masses and calibrating weights.
Like ASTM classes 0,1,2,3, these weights meet or exceed specifications as defined in the ANSI/ASTM E617 standard. The ASTM Class 4 is used to calibrate semi-analytic balances and is an appropriate size for student use. These Troemner™ weights are highly resistant to corrosion thanks to an alloyed stainless steel available only to Troemner and among the finest in state primary standards for manufacturing.
The class 4 precision weights (and Troemner™ Class 2, 3 and 4) are 1 g and larger, and are produced from two pieces of material: the body of the weight and the knob of the weight. This lifting knob is specifically designed for use with forceps, tweezers, and other lifting devices. The knob has a thread that screws directly into the body and is tightened. The weights are easy to recognizable as the top of the weight is marked with a nominal value.
Troemner™ is the only private mass metrology laboratory in the world accredited for E1 measurements with uncertainties at 1/3 the E1 tolerance. The company is home to a seasoned staff of metrologists and high-end calibrators offering the most precise balances and finest mass comparators on the market.