1.1 This test method covers the determination of the nitrogen content of all types of leather, wet blue and wet white. The nitrogen content is used to calculate the hide substance (protein fiber) content of leather, wet blue and wet white.

Note 1—The original test method for leather was essentially a composite of Method 6441 of Federal Test Method Standard No. 311 and Method B5 of the American Leather Chemists Association.

Note 2—Melamine, if present in bonded leather, could give an artificially high value for the calculation of protein fiber.

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.