The “Clear and Bright” test is a visual check and conducted to detect water or other solid contaminants in the fuel. Any evidence of external contaminants renders the fuel as “not suitable for use” and points to a requirement of further laboratory analysis.

Delivered fuel must be clean, bright and not contaminated with free water. “Clear” is a visual condition of fuel with the absence of cloud, emulsion, visible particulate matter or entrained water. “Bright” is the quality of fuel refers to the shiny and sparkling appearance of clean and dry fuel. The “bright and clear” condition of the fuel is not dependent on the natural colour of the fuel.