ASTM WK68927

    Revision of D6878 / D6878M - 17 Standard Specification for Thermoplastic Polyolefin Based Sheet Roofing

    (What is a Work Item?)

    Active Standard: D6878 / D6878M - 19

    Developed by Subcommittee: D08.18 | Committee D08 | Contact Staff Manager



    WK68927


    Keywords

    flexible sheet; roofing; roofing material; single-ply roofing membrane; thermoplastic polyolefin; TPO;;

    Rationale

    The wording within section 4. Physical Properties and Tolerances of ASTM D6878 Standard Specification for Thermoplastic Polyolefin Based Sheet Roofing is as follows: 4.2 The tolerance for time conditions (aging, weathering, and so forth) is+/-15 min or 1% of the period, whichever is greater, unless otherwise specified. Section 7.9 Heat Aging within the referenced standard requires an aging period of either (1) 5376 h (224 days or 32 weeks) at 116C [240F]; or (2) 1344 h (56 days or 8 weeks) at 135C [275F]. Due to the long duration of the heat aging test, a tolerance of +/-15 min as referenced in section 4.2 is not realistic. Using the +/-1% option yields a tolerance that is too wide (5376 hours x 0.01 = +/-54 hours or 1344 hours x 0.01 = +/-13 hours). There is precedent for a +/-6 hour tolerance on longer duration tests. Within ASTM D5869 Dark Oven Heat Exposure of Roofing and Waterproofing Materials the test duration is defined as either 35, 90 or 180 days and the time tolerance is specified as+/-0.25 days (6 hours). Based on the fact that section 4.2 specifies a tolerance that is inappropriate for the relatively long duration of the heat aging test period and the precedent established in ASTM D5869, a tolerance of +/-6 hours for the duration of the heat aging test within ASTM D6878 is being balloted.

    Citing ASTM Standards
    Back to Top
    Work Item Status

    Date Initiated:
    07-02-2019

    Technical Contact:
    Randall Ober

    Item:
    011

    Ballot:
    D08 (19-03)

    Status:
    Negative Votes Need Resolution