Course details

Overview ?

This course will instruct and evaluate you on basic concepts of uncertainty management. You will understand and describe the terminology, concepts, and procedures relating to ISO compliance and uncertainty management including tolerances, specifications, accuracy, uncertainty ratios, guard banding, and changes to and adjustment of inspection decision rules.

Learning Objectives:

Understand and apply key concepts relating to specifications, tolerances and measurement uncertainty quality
Read and interpret published specifications
Calculate accuracy ratios and guard bands for various purposes

Who Should Attend:

Calibration Coordinators, Calibration Technicians and Engineers, Quality Coordinators and those seeking understanding of the ISO 17025 standard and compliance to it.

Outline:

Introduction
- Communicating about measurements and measurement equipment
What is a Specification?
- Why do we need specifications?
- The use of specifications in measurement and metrology
- The form(s) taken by specification
- Some examples of specifications of measuring equipment
- How to read and interpret specifications
- The importance of specifications in calibration
- What it means to be in or out of spec.
- Practice reading, interpreting, calculating
What is a Tolerance?
- How are tolerances stated?
- What is the difference between a tolerance and a specification?
- Some examples of tolerances of measuring equipment
- How to read and interpret tolerances
- The importance of tolerances in calibration
- What it means to be in or out of tolerance
- Practice reading, interpreting, calculating
Measurement Uncertainty (this is not a full treatment, just an intro in context)
- Definitions (in context) of measures of measurement reliability and quality
- Accuracy
- Precision
- Resolution
- Repeatability and Reproducibility
- Traceability
- How do these definitions fit with specifications and tolerances?
- Special cases: floor specs, percent of full scale versus percent of reading, ppm, values near zero
- Calculation of measurement uncertainty – budgets
- Converting specifications and tolerances to uncertainty
- Practice calculating
Accreditation (rules relating to specifications and tolerances)
Ratios
- The 10:1 principle; 4:1, 3:1
- What did they mean in the past: Definitions in MIL-STD-45662
- What do they mean now? Definitions in ANSI/NCSL Z-540-1, ISO 10012-1 and ISO/IEC 17025. Are they useful? If so, why?
- Accuracy ratios, tolerance ratios, uncertainty ratios
- Ratios and traceability
- Practice calculations
Specifications, Tolerances, and Uncertainty
- Inspection and test
- Errors of Type I
- Errors of Type II
- Decision rules
- Definitions
- Applying them
- Responsibility (whose)
- Measurement uncertainty and decision rules
Changes to and Adjustment of Decision Rules
- Guard banding
- Determining conformance to identified metrological specifications and taking measurement uncertainty into account
- Practice calculation