): The difference between two single and independent results obtained by different operators working in different laboratories on identical test material.

While versatile, the standard notes that volatile water-soluble materials may be measured as water, potentially affecting the final result.

As the vapors condense, the water separates from the solvent and settles at the bottom of a graduated trap. The solvent overflows and flows back into the distillation flask. 2. Why Measuring Water Content Matters

Industrial-grade xylene, toluene, or petroleum naphtha, depending on the specific material being tested. Step-by-Step Testing Procedure

The underlying chemistry of ASTM D95 relies on co-distillation, often referred to as the Dean-Stark distillation method.

"Standard Test Method for Water in Petroleum Products and Bituminous Materials by Distillation," covers the determination of water in the range of 0% to 25% by volume

The is an essential document for any quality control laboratory handling petroleum products. Whether you are testing crude oil, fuel oil, or asphalt, this distillation method offers a reliable, visual, and direct way to measure water contamination.

: A representative sample of crude oil is carefully prepared according to the standard's guidelines.