The accuracy of volumetric glassware can have a significant impact on experimental and testing results. This is why quality glassware is made in compliance with ASTM or industry recognized standards. In fact, PYREX glassware has long been, and will continue to be, made to ASTM standards.But now we’ve taken our glassware quality control to an even higher level. As an added assurance of accuracy and precision, PYREX volumetric glassware is now tested and calibrated in an ISO/IEC 17025 accredited laboratory.