Reference Material (RM) Documentation - A look at ISO Guide 31

ISO Guide 31 provides information to aid RM producers in the preparation of clear and concise documentation. This includes product information sheets and certificates of analysis (CoAs).

Required Information:

Title of the Document

The document is required to have a distinct title. Inorganic Ventures (IV) uses a Certificate of Analysis (CoA) for certified reference materials (CRMs) and a Product Information Sheet for non-certified reference materials (RMs).

Name and Description of the RM

Every IV produced RM has a unique code (catalog number) and batch number (lot number) to distinguish it from all other materials. Information describing the RM, including the purity and lot number of the starting material, matrix, and value/analyte must also be included. This serves as a more detailed explanation of the name.

Name and Contact Details of the RM Producer

The name and contact information is required, however, the producer determines the specific contact details, so it may differ from one company to the next. This information can be found at the top of IV’s documentation.

Intended Use

The primary purpose for which the RM is issued should be stated directly on the certificate. This statement is not intended to restrict the use for other purposes. Sufficient information must be provided, so users are able to determine if it will meet requirements.

Minimum Sample Size/Homogeneity

Information related to the homogeneity of the RM is included along with a minimum sample size for the end users.

Period of Validity

The period of validity or expiry date of the RM must be clearly stated and the fitness for purpose not guaranteed beyond this date.

Storage and Handling Information

Recommendations pertaining to storage and handling are vital to the proper use of a RM. The information provided in Section 7.0 of IV’s documentation is specific to that RM, so it is important for the end user to review this section before use.

Document Version and Page Numbers

The version must be clearly stated by using a unique number or approval date. Revisions to the document should also be included for reference. Pagination is required.

Property of interest, property value and associated uncertainty

A clear statement of the properties, with values and uncertainties, is required. Certified values must also be clearly indicated and distinguished from any other values provided.

Measurement Methods

Detailed information of the method used is critical whether the value is method dependent or not. A reference to a published method may also be included.

IV Certificate of Analysis Spotlight – Section 3.0

Certified Values and Uncertainties

Calculating Certified Value and Uncertainty

Characterization of CRM/RM 

Metrological Traceability

The statement of metrological traceability shall include a specification of the measurand(s) and the measurement scale. Information about measurement procedures should also be included. 

Name and Function of the RM Producer’s Approving Officer

Names of the officers who accept the responsibility for the contents of the certificate must appear on the document.

Dr. Paul Gaines, Chairman and Senior Technical Director, is the certifying officer. 

Optional Information:

Other useful Information such as health and safety information (or reference to the Safety Data Sheet (SDS), subcontractors, legal notice, reference to a certification report, and/or indicative values may also be included, if applicable.

Going Beyond the Requirements:

While not required, Inorganic Ventures has chosen to include the following information as an additional benefit to our customers:

  • Trace Metallic Impurities (TMI): Providing data related to TMI gives the end user a much greater understanding of the solution's purity.
  • Chromatograms, for selected IC standards
  • Atomic spectroscopic information such as recommended masses/wavelengths, interferences and detection limits, for selected CG standards.

It is clear that ISO Guide 31 is essential for every RM producer to ensure that documentation is standardized and meets the end users’ needs.