Mark Ruefenacht shares his time as an employee with Rice Lake Weighing Systems as the Technical Director of Precision Products and as an instructor and researcher at the National Institute of Standards & Technology (NIST); teaching courses on mass (weights), balances & scales, measurement traceability, and measurement uncertainty. He develops NIST training course work, handbooks, and coordinates/analyzes NIST proficiency tests. Mark has been an ISO/IEC 17025 lead and technical assessor with NVLAP since 2006. Additionally, he provides ongoing technical training and consultation to various ISO/IEC 17025 & ISO 17020 accrediting bodies, calibration laboratories, forensic laboratories, pharmaceuticals, and bio-technology companies. He has specialized in the highest echelons of mass/weight calibrations and mass-related measurements (e.g., balances/scales, force, torque, pipettes, volume, etc.), pharmaceutical measurements, and forensic measurements & tests. Mark is the technical contact for ASTM E617 (Mass & Weights) and ASTM E898 (Balances & Scales).