California ICC UST Service Technician Practice Exam

Gasoline vapors are indeed lighter than air, making the correct assertion "True." When gasoline evaporates, it produces vapors that rise into the atmosphere because they have a lower density than the surrounding air. This characteristic is important for safety and environmental considerations, particularly in the context of underground storage tanks and fuel dispensing systems, as it influences how vapors may accumulate and disperse. It is essential for technicians and safety personnel to understand the behavior of gasoline vapors, especially when managing potential leaks or spills, ensuring proper ventilation, and preventing fire hazards. In contrast, the answer stating "False" does not align with the physical properties of gasoline vapors, which have been studied and documented thoroughly in the context of fuel handling and safety practices. The other choices discussing conditions like "only when heated" or "only in closed systems" do not accurately reflect the consistent behavior of gasoline vapors under standard atmospheric conditions.