ASTM WK75478

    Revision of D974 - 14e2 Standard Test Method for Acid and Base Number by Color-Indicator Titration

    (What is a Work Item?)

    Active Standard: D974 - 21

    Developed by Subcommittee: D02.06 | Committee D02 | Contact Staff Manager



    acid number; base number; color indication titration; petroleum products;;


    This is the second time this ballot has been submitted. During the first balloting round, it was noted that the impact to the technical equivalency to IP 139/98 had not been completed. That has been corrected with this ballot. Only the sections that have proposed revisions have been presented for consideration. The proposed revisions for this ballot only concern portions of Annex 1 Specifications for -Naphtholbenzein and Annex 2 - Test Method for Determining pHr Range of -Naphtholbenzein Indicator, of the ASTM D974 standard. Procedures within ASTM D664 (Standard Test Method for Acid Number of Petroleum Products by Potentiometric Titration) are currently referenced as part of the ASTM D974 Annex 2 method. The ASTM D664 method has been revised to replace pH buffer 10 as endpoint and has changed from using nonaqueous buffers to commercial aqueous buffers. These revisions have resulted in inconsistencies between ASTM D974 Annex 2 and ASTM D664. The proposed changes will improve alignment between these two ASTM standards. As the proposed changes could impact the technical equivalency to IP 139, the correlation between the two methods was re-assessed (see attached technical comparison updated 12 Jan 21). This review discovered some minor editorial differences that are also addressed in this ballot and it is the first time balloting those sections. These new ballot items are the highlighted rows. All changes have been discussed with the EI group, including new sections, and Technical Equivalency is deemed not affected with the proposed changes. An EI work item has been opened and is pending the outcome of this ballot (139-20-1). The updated Technical Equivalency comparison and Checklist for Maintenance of Technically Equivalent ASTM/EI Standards have been attached to this ballot for voter reference. IP 139/98 (2017) is available for review upon request for the purposes of this ballot. The ASTM footnote for joint EI methods will be updated upon approval of this ballot.

    Citing ASTM Standards
    Back to Top
    Work Item Status

    Date Initiated:

    Technical Contact:
    Carol Gebhart


    D02 (21-04)

    Ballot Item Approved as D974-2021 and Pending Publication