4.1 The iodine adsorption number is useful in characterizing carbon blacks. It is related to the surface area of carbon blacks and is generally in agreement with nitrogen surface area. The presence of volatiles, surface porosity, or extractables will influence the iodine adsorption number. Aging of carbon black can also influence the iodine number.

1.1 This test method covers the determination of the iodine adsorption number of carbon black.

1.2 The iodine adsorption number of carbon black has been shown to decrease with sample aging. New SRB HT Iodine Standards have been produced that exhibit stable iodine number upon aging. One or more of these SRB HT Iodine Standards are recommended for daily monitoring (x-charts) to ensure that the results are within the control limits of the individual standard. Use all SRB HT Iodine Standards for standardization of iodine testing (see Section 8) when target values cannot be obtained.

1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.4 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 and health practices and determine the applicability of regulatory limitations prior to use.