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Reference Material
Reference documents and regulatory information relevant to ISO 17025 compliance.
ISO/IEC 17025:2017
Structured integration of ISO/IEC 17025:2017, providing a reference for testing and calibration laboratory requirements. The official ISO PDFs remain the primary authoritative source.
7 Process requirements
7.6 Evaluation of Measurement Uncertainty
Laboratories shall identify and evaluate contributions to measurement uncertainty using appropriate methods of analysis, ensuring accurate and reliable results in calibration and testing.

Reference Material
Reference documents and regulatory information relevant to ISO 17025 compliance.
- ISO/IEC 17025:2017
  Structured integration of ISO/IEC 17025:2017, providing a reference for testing and calibration laboratory requirements. The official ISO PDFs remain the primary authoritative source.
  - Foreword
  - Introduction
    This document establishes requirements for laboratories to ensure competence, confidence, and valid results, aligning with ISO 9001 principles. It emphasizes risk-based planning, cooperation, and harmonization of standards while outlining key terminology usage.
  - 1 Scope
    This document defines the general requirements for laboratory competence, impartiality, and consistent operation, applicable to all organizations conducting laboratory activities.
  - 2 Normative References
    This section lists documents that are referenced in the text as requirements. Dated references apply to specific editions, while undated references apply to the latest version, including amendments.
  - 3 Terms and Definitions
    This section defines the terms used in this document. It references ISO/IEC Guide 99 and ISO/IEC 17000, along with additional terms specific to this standard.
  - 4 General requirements
  - 5 Structural requirements
  - 6 Resource requirements
  - 7 Process requirements
    - 7.1 Review of Requests, Tenders, and Contracts
      The laboratory shall establish a procedure for reviewing requests, tenders, and contracts to ensure customer requirements are met, resources are available, and contract deviations are managed appropriately.
    - 7.2 Selection, verification and validation of methods
    - 7.3 Sampling
      The laboratory shall have a sampling plan and method to ensure the validity of subsequent testing or calibration results.
    - 7.4 Handling of Test or Calibration Items
      The laboratory shall establish procedures to ensure the integrity of test or calibration items during transportation, receipt, handling, storage, and disposal.
    - 7.5 Technical Records
      The laboratory shall maintain technical records that document laboratory activities, results, and sufficient information to ensure traceability, facilitate identification of factors affecting measurement results, and allow for repetition of the activity under conditions as close as possible to the original.
    - 7.6 Evaluation of Measurement Uncertainty
      Laboratories shall identify and evaluate contributions to measurement uncertainty using appropriate methods of analysis, ensuring accurate and reliable results in calibration and testing.
    - 7.7 Ensuring the Validity of Results
      The laboratory shall establish procedures for monitoring the validity of results, applying statistical techniques where appropriate, and taking corrective actions when necessary to maintain result accuracy and reliability.
    - 7.8 Reporting of results
    - 7.9 Complaints
      The laboratory shall establish a documented process for receiving, evaluating, and making decisions on complaints, ensuring appropriate tracking, resolution, and communication with complainants.
    - 7.10 Nonconforming Work
      The laboratory shall have a procedure that shall be implemented when any aspect of its laboratory activities or results of this work do not conform to its own procedures or the agreed requirements of the customer.
    - 7.11 Control of Data and Information Management
      The laboratory shall establish and maintain control over data and information management systems, ensuring data integrity, protection, validation, and compliance with applicable requirements.
  - 8 Management system requirements
  - Annex A (Informative) Metrological Traceability
  - Annex B (Informative) Management System Options
    This annex provides additional information on the management system options available to laboratories, ensuring conformity to ISO 9001 while fulfilling the requirements of this document.

7.6 Evaluation of Measurement Uncertainty

Laboratories shall identify and evaluate contributions to measurement uncertainty using appropriate methods of analysis, ensuring accurate and reliable results in calibration and testing.

7.6.1 Identification of Measurement Uncertainty Contributions

Laboratories shall identify the contributions to measurement uncertainty. When evaluating measurement uncertainty, all significant contributions, including those arising from sampling, shall be taken into account using appropriate methods of analysis.

7.6.2 Measurement Uncertainty in Calibration

A laboratory performing calibrations, including calibration of its own equipment, shall evaluate the measurement uncertainty for all calibrations.

7.6.3 Measurement Uncertainty in Testing

A laboratory performing testing shall evaluate measurement uncertainty. Where the test method precludes rigorous evaluation of measurement uncertainty, an estimation shall be made based on:

An understanding of the theoretical principles of the method.
Practical experience of the method’s performance.

Note:

In cases where a well-recognized test method specifies limits to the values of the major sources of measurement uncertainty and specifies the format for presenting results, compliance with the test method and reporting instructions satisfies the requirements of 7.6.3.

Note:

For a particular method where the measurement uncertainty of results has been established and verified, there is no need to evaluate measurement uncertainty for each result if the laboratory can demonstrate that the identified critical influencing factors are under control.

Additional References

Note:

For further information, see: