BS ISO 33401:2024
Reference materials. Contents of certificates, labels and accompanying documentation

Standard No.

BS ISO 33401:2024

Release Date

2024

Published By

British Standards Institution (BSI)  GB  /  BSI

Latest

BS ISO 33401:2024

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Introduction

Background of Standard Evolution and Technological Innovation

ISO 33401:2024 replaces the 2015 version of ISO GUIDE 31, realizing the upgrade and transformation from a guide to an international standard. The main technical changes include:

• Added standardization requirements for Product Information Sheet
• Reconstructed the reference material document classification system (RM Certificate/PIS)
• Strengthened the requirements for coordinated implementation with ISO 17034

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Analysis of core requirements

Document type distinction

Elements	Product Information Sheet (PIS)	Reference Material Certificate (RM Certificate)
Metrological Traceability Declaration	Optional	Mandatory
Uncertainty of Characteristic Value	Optional	Mandatory
Information of the person responsible for approval	Optional	Mandatory

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Key elements of the label

The standard clearly stipulates that the label must include:

1. Unique identifier of the reference material (same as the certificate number)
2. Contact information of the manufacturer
3. Health and safety warning symbols (if applicable)
4. Prohibition of marking characteristic values to avoid misuse

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Implementation recommendations

Key points for compliance of manufacturers

• Establish a special documentation system for operationally defined measurement quantities (see clause 5.2.14)
• The validity statement needs to be based on the stability study of ISO Guide 35
• The new version of the certificate needs to include the version control identification (5.2.13)

Laboratory use recommendations

• Verify that the interchangeability information (clause 5.2.9) meets the test method requirements
• Retain certificate version records to maintain traceability integrity
• Minimum sampling requirements must be strictly enforced (5.2.7)

BS ISO 33401:2024 Referenced Document

• ISO Guide 30:2015 Reference materials - Selected terms and definitions

BS ISO 33401:2024 history

• 2024 BS ISO 33401:2024 Reference materials. Contents of certificates, labels and accompanying documentation

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