ASTM D7235-21a
Standard Guide for Establishing a Linear Correlation Relationship Between Analyzer and Primary Test Method Results Using Relevant ASTM Standard Practices

Standard No.

ASTM D7235-21a

Release Date

2021

Published By

American Society for Testing and Materials (ASTM)

Latest

ASTM D7235-21a

Scope

1.1 This guide covers a general methodology to develop and assess the linear relationship between results produced by a total analyzer system versus the results produced by the corresponding primary test method (PTM) that the analyzer system is intended to emulate, using the principles and approaches outlined in relevant ASTM standard practices and guides. 1.2 This guide describes how the statistical methodology of Practice D6708 can be employed to assess agreement between the PTM and analyzer results, and, if necessary, develop linear correlation to further improve the agreement over the complete operating range of the analyzer. For instances where there is insufficient variation in property level to apply the Practice D6708 multi-level methodology, users are referred to Practice D3764 to perform a level specific bias evaluation. The correlation relationship information obtained in the application of this guide is applicable only to the material type and property range of the materials representative of those used to perform the assessment. Users are cautioned against extrapolation of the relationship beyond the material type and property range being studied. 1.3 This guide applies if the process stream analyzer system and the primary test method are based on the same measurement principle(s), or, if the process stream analyzer system uses a direct and well-understood measurement principle that is similar to the measurement principle of the primary test method. If the process stream analyzer system uses a different measurement technology from the primary test method, provided that the calibration protocol for the direct output of the analyzer does not require use of the PTM, this practice also applies. 1 This guide is under the jurisdiction of ASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of Subcommittee D02.25 on Performance Assessment and Validation of Process Stream Analyzer Systems. Current edition approved Dec. 1, 2021. Published December 2021. Originally approved in 2005. Last previous edition approved in 2021 as D7235 – 21. DOI: 10.1520/D7235-21A. *A Summary of Changes section appears at the end of this standard Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. 1 8QLYHUVLW\RI7RURQWR 8QLYHUVLW\RI7RURQWR SXUVXDQWWR/LFHQVH$JUHHPHQW1RIXUWKHUUHSURGXFWLRQVDXWKRUL]HG 'RZQORDGHGSULQWHGE\ &RS\ULJKWE\$670,QW O DOOULJKWVUHVHUYHG )UL'HF*07 1.4 This guide does not apply if the process stream analyzer system utilizes an indirect or mathematically modeled measurement principle such as chemometric or multivariate analysis techniques where results from PTM are required for the chemometric or multivariate model development. Users should refer to Practices D8321 and D6122 for detailed correlation and model validation procedures for these types of analyzer systems. NOTE 1—For example, this guide would apply for the comparison of benzene measurements from a mid-infrared process analyzer system based on Test Method D6277 to those obtained using PTM Test Method D3606, a gas chromatography based test method. For each sample, the midinfrared spectrum is converted into a single analyzer result using methodology (Test Method D6277) that is independent of the primary test method (Test Method D3606). However, when the same analyzer uses a multivariate model to correlate the measured mid-infrared spectrum to Test Method D3606 reference values using the methodology of Practice D8321, this guide does not apply. In this case, the direct output of the analyzer is the spectrum, and the conversion of this multivariate output to an analyzer result require results from the primary test method. 1.5 This guide assumes that the analyzer sampling system is fit for use, and both analyzer and lab systems are in statistical control during the execution of the required tasks. Procedures for testing for proper function of the analyzer sampling system are beyond the scope of this guide. For ascertaining whether the systems are in statistical control, refer to Practice D6299 or other technical equivalent documents. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ASTM D7235-21a Referenced Document

• ASTM D3606 Standard Test Method for Determination of Benzene and Toluene in Finished Motor and Aviation Gasoline by Gas Chromatography
• ASTM D3764 Standard Practice for Validation of Process Stream Analyzer Systems
• ASTM D4177 Standard Practice for Automatic Sampling of Petroleum and Petroleum Products
• ASTM D5191 Standard Test Method for Vapor Pressure of Petroleum Products (Mini Method)
• ASTM D6122 Standard Practice for Validation of Multivariate Process Infrared Spectrophotometers
• ASTM D6277 Standard Test Method for Determination of Benzene in Spark-Ignition Engine Fuels Using Mid Infrared Spectroscopy
• ASTM D6299 Standard Practice for Applying Statistical Quality Assurance and Control Charting Techniques to Evaluate Analytical Measurement System Performance*， 2023-07-01 Update
• ASTM D6624 Standard Practice for Determining a Flow-Proportioned Average Property Value (FPAPV) for a Collected Batch of Process Stream Material Using Stream Analyzer Data
• ASTM D6708 Standard Practice for Statistical Assessment and Improvement of Expected Agreement Between Two Test Methods that Purport to Measure the Same Property of a Material*， 2024-03-01 Update
• ASTM D7453 Standard Practice for Sampling of Petroleum Products for Analysis by Process Stream Analyzers and for Process Stream Analyzer System Validation*， 2022-04-01 Update
• ASTM D7808 Standard Practice for Determining the Site Precision of a Process Stream Analyzer on Process Stream Material*， 2022-04-01 Update
• ASTM D8321 Standard Practice for Development and Validation of Multivariate Analyses for Use in Predicting Properties of Petroleum Products, Liquid Fuels, and Lubricants based on Spectroscopic Measurements*， 2022-04-01 Update
• ASTM E1655 Standard Practices for Infrared Multivariate Quantitative Analysis*， 2024-04-20 Update

ASTM D7235-21a history

• 2021 ASTM D7235-21a Standard Guide for Establishing a Linear Correlation Relationship Between Analyzer and Primary Test Method Results Using Relevant ASTM Standard Practices
• 2021 ASTM D7235-21 Standard Guide for Establishing a Linear Correlation Relationship Between Analyzer and Primary Test Method Results Using Relevant ASTM Standard Practices
• 2016 ASTM D7235-16 Standard Guide for Establishing a Linear Correlation Relationship Between Analyzer and Primary Test Method Results Using Relevant ASTM Standard Practices
• 2014 ASTM D7235-14 Standard Guide for Establishing a Linear Correlation Relationship Between Analyzer and Primary Test Method Results Using Relevant ASTM Standard Practices
• 2010 ASTM D7235-10 Standard Guide for Establishing a Linear Correlation Relationship Between Analyzer and Primary Test Method Results Using Relevant ASTM Standard Practices
• 2005 ASTM D7235-05 Standard Guide for Establishing a Linear Correlation Relationship Between Analyzer and Primary Test Method Results Using Relevant ASTM Standard Practices