Gasoline vapor tends to settle low in bilge because it is heavier than air. Which option best reflects this property?

Gasoline vapor tends to settle low in bilge because it is heavier than air. Which option best reflects this property?

• A. Gasoline vapor
• B. LPG vapor
• C. CNG vapor
• D. Hydrogen vapor

Answer: (A)

Vapor density relative to air determines where vapors pool: heavier-than-air vapors tend to collect in the lowest parts of a space, while lighter-than-air vapors rise and dissipate upward. Gasoline vapor is denser than air, so in a bilge it naturally settles toward the bottom, creating a hazardous pocket of vapor. Among the options, gasoline vapor best reflects this behavior because it directly matches the described tendency to be heavier than air and to accumulate low. Hydrogen vapor and methane/CNG vapor are lighter than air and would not settle low, and LPG is also heavier than air but the scenario centers on gasoline’s behavior as described.

Vapor density relative to air determines where vapors pool: heavier-than-air vapors tend to collect in the lowest parts of a space, while lighter-than-air vapors rise and dissipate upward.

Gasoline vapor is denser than air, so in a bilge it naturally settles toward the bottom, creating a hazardous pocket of vapor. Among the options, gasoline vapor best reflects this behavior because it directly matches the described tendency to be heavier than air and to accumulate low. Hydrogen vapor and methane/CNG vapor are lighter than air and would not settle low, and LPG is also heavier than air but the scenario centers on gasoline’s behavior as described.