3.1 Vegetable tanning materials are natural products containing various substances of varying composition, concentration and quality.

3.2 The methods referenced are useful for analyzing and testing vegetable tanning materials for moisture, water-extractable substances, cold-soluble fractions, tannins, non-tannins, acidity, tanning properties, the color of tanned leather, and the presence or absence of certain admixtures.

1.1 This practice is intended for use in the chemical analysis of all vegetable tanning materials.

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

1.3 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.