Kilogram (IMAGE) DOE/Sandia National Laboratories Caption Hy Tran examines a kilogram sample in a mass comparator at Sandia’s Primary Standards Laboratory. Credit Randy Montoya Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.