ASTM WK45936

    Revision of F2702 - 08 Standard Test Method for Radiant Heat Performance of Flame Resistant Clothing Materials with Burn Injury Prediction

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    Active Standard: F2702 - 08

    Developed by Subcommittee: F23.80 | Committee F23 | Contact Staff Manager



    WK45936

    1. Rationale

    Standard Test Method for Radiant Heat Performance of Flame Resistant Clothing Materials with Burn Injury Prediction. This revision is to address a persuasive negative from the F23 (13-01) ballot (F2702 revalidation) by Harry Winer. He noted that an earlier study of instrument performance (done around 1980) showed that the age of the lamps and the variation of the color temperatures of the lamps in the array could affect the results. At 80 kW/m2 [1.9 cal/cm2s], the study noted that due to closeness of the test sample to the quartz lamp array, large differences in color temperatures resulted in a significant bias for the measured specimen performance. Essentially, the new text addresses radiant quartz lamp output quality (uniformity), calibration, and fitness for use. Proposed New Text (underlined) and section renumbering for 9. Preparation, Calibration, and Maintenance of Apparatus 9.2 Verification of Quartz Bulb Assembly Output Uniformity: 9.2.1 Initial Output Verification of New Lamps: 9.2.1.1 Complete the radiant heat flux calibration in 9.1 for an output of 84 kW/m2 [2 cal/cm2s], then use an optical pyrometer to obtain at least five (5) measured color temperatures of each lamp through the approximate center of the lamp. Alternatively, use a radiometer in the sample specimen position to measure at least five (5) measured values of radiant energy output at the approximate center of each lamp (collimated so that only one lamp is visible to the radiometer). 9.2.1.2 Average the five measured values of each lamp and assign this its color temperature or radiant energy output (based on the measurement technology used). 9.2.1.3 Average the values from all five (5) lamps and assign this the array value. 9.2.1.4 If an optical pyrometer is used Compare the average value of each of the lamps in the array from 9.2.1.2 to the array average from 9.2.1.3. If any of the individual lamp averages are greater than 15 K of the array average, replace the identified lamp and repeat 9.1 and 9.2.1. 9.2.1.5 If a radiometer is used - Compare the average radiometer value of each of the lamps in the array from 9.2.1.2 to the array average from 9.2.1.3. If any of the individual lamp averages are greater than 15 % of the array average, replace the identified lamp and repeat 9.1 and 9.2.1. 9.2.1.6 If a variable power transformer supply is used to power the lamps record the voltage of the new calibrated lamp array to the nearest 0.5 VAC. 9.2.2 Output Verification of Lamps in Service: 9.2.2.1 Follow the procedure in 9.2.1 to re-verify the individual lamps and the lamp array outputs at intervals not to exceed 25 h of lamp operating time at a heat flux output of 84 kW/m2 [2 cal/cm2s], or intervals not to exceed 100 h of lamp operating time at a heat flux output of 21 kW/m2 [0.5 cal/cm2s], or a voltage change of more than 5V for an output setting of 84 kW/m2 [2 cal/cm2s] from that noted in 9.2.1.6 (for systems using a variable power transformer supply to power the lamps). Note The operating life expectancy of the 500W quartz infrared lamps specified in 6.1.1 is typically 5000 h at full output per the manufacturer (~130 kW/m2 [3.1 cal/cm2s]). However, experience has shown that the age and the variation in color temperature of the lamps in the array can affect the incident heat flux delivered to the test specimen. 9. 2 3 Sensor Care: 9. 2 3 .1 Initial Temperature Cool the sensor prior to and after an exposure with a jet of air or contact with a cold surface so that it is in thermal equilibrium and at room temperature prior to positioning the sensor behind the test specimen. Thermal equilibrium is obtained when the sensor temperature is within 1C of room temperature for a 60 second period prior to use. 9. 2 3 .2 Surface Reconditioning Wipe the sensor face with a nonabrasive material immediately after each exposure, while hot, to remove any decomposition products that condense on the sensor since these could be a source of error. If a deposit collects and appears to be irregular or thicker than a thin layer of paint, the sensor surface requires reconditioning. Carefully clean the cooled sensor with solvent, making certain there is no ignition source nearby. If bare copper is showing, repaint the surface with a thin layer of flat black high temperature spray paint identified in 6.1.5.1. Perform at least one calibration run on the newly painted sensor before using it in a test run. 9. 3 4 Specimen Holder Care Use dry specimen holders at 1C of ambient temperature for test runs. Alternate with several sets of holders to permit cooling between runs, or force cool with air or water. Clean the holder with a non-aqueous solvent when it becomes coated with tar, soots, or other decomposition products.


    Keywords

    apparel; protective clothing; radiant heat protection; radiant heat performance, flame resistance;
    Citing ASTM Standards
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    Work Item Status

    Date Initiated:
    05-02-2014

    Technical Contact:
    Roger Parry

    Item:
    012

    Ballot:
    F23 (14-02)

    Status:
    Negative Votes Need Resolution