Ethylene is not a dual-phase fuel.

Ethylene is not a dual-phase fuel.

• A. False
• B. Sometimes
• C. True
• D. Not determinable

Answer: (C)

Understanding how fuels exist in different phases at typical conditions helps explain fire hazards. Ethylene is a gas at room temperature and pressure, with a boiling point far below ambient conditions. Because it does not present a liquid phase under normal environmental conditions, it cannot form both liquid and vapor phases together in a standard fire scenario. That’s why the statement that ethylene is not a dual-phase fuel is true. (If you cooled or compressed it enough, it could be liquefied, but under ordinary conditions it remains a single phase—the gas.)

Understanding how fuels exist in different phases at typical conditions helps explain fire hazards. Ethylene is a gas at room temperature and pressure, with a boiling point far below ambient conditions. Because it does not present a liquid phase under normal environmental conditions, it cannot form both liquid and vapor phases together in a standard fire scenario. That’s why the statement that ethylene is not a dual-phase fuel is true. (If you cooled or compressed it enough, it could be liquefied, but under ordinary conditions it remains a single phase—the gas.)