All equipment used on the project should be given a thorough visual inspection for leakage of any substance that might contaminate the asphalt, aggregate, or prevent adhesion to the pavement surface. These substances include fuel (both diesel and gasoline), hydraulic fluid, engine coolant, crankcase oil, and transmission fluid.

Inspecting for leaks is extremely important, not only before the project begins, but throughout the entire project. If a leak is detected in any piece of equipment, the equipment should be removed from the roadway until it is repaired.