A sample showing sediment and water would be detected by which test?

• A. Viscosity test
• B. Density test
• C. Gas test
• D. BS&W test

Answer: (D)

Bottom sediment and water detection is tested by a method designed to reveal free water and settled solids in a liquid sample. The BS&W test—Bottom Sediment and Water—is used to quantify how much water and sediment are present in fuels and lubricants. In this test, the sample is allowed to settle or is centrifuged; because water and sediment are denser than the hydrocarbon, they collect at the bottom and can be measured. This directly targets the presence of both impurities in the liquid, which is crucial for ensuring fuel system reliability and preventing issues like corrosion or clogging. Other tests measure properties like flow behavior (viscosity), overall density, or the presence of gases, but they don’t specifically isolate bottom sediment and water.