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5579: C-RMAP Tutorial 1: Balance and Scale Calibration and Uncertainties (3 days)

This NIST Balance Calibration and Uncertainties Seminar covers the calibration and use of analytical weighing instruments (balances and laboratory/bench-top scales), including sources of weighing errors in analytical environments, methodologies for quantifying the errors, and computation of balance calibration uncertainty and global (user) uncertainty. Attention will be given to error sources, selection of reference standards, and various calibration procedures used in the weighing industry. Approximately 50 percent of the time will be spent doing hands-on exercises, calibrating a variety of balances, accumulating data, and developing uncertainty budgets. The focus will then move to the use of balances in an analytical environment and regulatory environment where compliance with pharmaceutical (FDA/ USP) and international requirements will be discussed and practiced. Methodologies for process measurement assurance techniques in analytical weighing will also be covered. Participants will leave with a working skill-set of balance calibration methods, uncertainty estimation, measurement assurance concepts & minimum sample quantity computations that can be applied directly to their calibration and/or use of weighing instruments. This NIST Seminar is designed for beginner to advanced users of balances, metrologists, ISO/IEC 17025 assessors and accreditation bodies, or calibration managers wanting a better understanding of balances and associated uncertainties in organizations where analytical weighing is an integral part of operations. All participants will receive a USB stick with a comprehensive collection of national and international references and documents.

Learning Objectives:

At the end of this seminar, using your references and notes, you will be able to:

  • Summarize the principles and concepts of Measurement Traceability, Measurement Assurance, and Measurement Uncertainty.
  • Explain the interrelationships between traceability, measurement assurance, and measurement uncertainty.
  • Select the appropriate reference standards for the calibration of weighing instruments.
  • Select the appropriate international or national method/procedure for the calibration and/or use of weighing instruments in the ISO/IEC 17025 or Regulatory environment.
  • Describe the NIST Eight-Step Process of Measurement Uncertainty Estimation.
  • Construct a procedure or outline for a balance calibration
  • Brainstorm, categorize and quantify potential error sources and uncertainty contributors to weighing devices.
  • Develop a basic uncertainty budget for weighing devices that is validated with the principles of measurement assurance.
  • Estimate the minimum sample quantify for weighing instruments.

Materials & Supplies:

All materials and supplies provided by seminar hosts.


Knowledge of basic and some advanced mathematics skills are needed to be successful in the Balance Calibration and Uncertainty Tutorial. There is no planned review of these basic mathematics topics during the tutorial.


Read Euramet Calibration Guide (CG)-18 before the seminar. The currently published version of CG-18 is found at: at the No.18│Guidelines on the Calibration of Non-automatic Weighing Instruments│TC-M│Version 4.0, 11/2015 link under the Mass and Related Quantities heading. The content of cg-18 will be discussed extensively during the tutorial, however early review will enhance your understanding of the concepts.

Submit the completed required mathematics exercises (MATH EXERCISES LINK) to at least 6 weeks prior to the tutorial. A score of 70 % correct must be achieved to participate in the tutorial.

It is also recommended that you complete the Recommended Math Exercises (Balance Math Exercises Rev) to enhance your participation in the tutorial.

Submit completed mathematics exercises for which you want feedback to The provided feedback will let you know which topic areas need some review.

Below is a list of resource's that will be helpful should you need review of the mathematics skills prior to the Balance Calibration & Uncertainty Tutorial:

Pre-Work Deadline:

Submit the math exercises (pre-work) according to instructions by COB on Friday, May 4, 2019.

Minimum Requirement(s):

Successful completion requires that participants fully participate in all classroom and laboratory exercises, turn in or present accurate work assignments, and be present for the entire course, in addition to successfully completing the Balance Calibration Mathematical Exercises.


This NIST Seminar is designed for beginner to advanced users of balances or calibration managers wanting a better understanding of balances and associated uncertainties in organizations where analytical weighing is an integral part of operations.


The registration fee for this tutorial is $200 and confirmed participants will be provided with payment instructions. The due date for payment is Monday, May 13, 2019.


Val Miller and Mark Ruefenacht,
Office of Weights and Measures
Phone: (301) 975 - 3602

Technology Requirement(s):

Laptop with spreadsheet capability and/or scientific calculator strongly encouraged.


NIST / Office of Weights and Measures

Orlando Marriott Lake Mary
1501 International Parkway,
Lake Mary, FL 32746
P 407.995.7016 | F 407.995.1101

Group rate: C-RMAP
Start date: 5/30/19 - End date: 6/8/19
Last day to book: 4/30/19

Marriott hotel(s) offering your special group rate: Orlando Marriott Lake Mary for 94 USD per night Anyone who has special reservation requests may contact the group housing office at Of course, guests may also book by phone at 800-380-7724 and reference the group name (C-RMAP) and arrival date. In order to get the guaranteed rate, you must book under the group block by one of these methods.

Created October 12, 2018, Updated February 5, 2019