Question 42

The Correct Answer is B **Why Option B ("Flammability") is Correct:** The primary hazard of both liquefied petroleum gas (LPG) and liquefied natural gas (LNG) is their extreme flammability. Both substances are stored as high-energy-density liquids but rapidly vaporize into gases that are easily ignitable within their respective flammable limits when released into the atmosphere. A leak can quickly create a large, explosive vapor cloud, making fire and explosion the most significant risk associated with handling, storage, and transport of these fuels. **Why the Other Options are Incorrect:** * **A) Temperature:** While both LPG and LNG are stored at very low (cryogenic, in the case of LNG) or cool temperatures, causing "cold burns" upon contact, this is a secondary, localized hazard, not the overall primary danger that dictates major safety protocols and risk assessment (which is explosion/fire). * **C) Toxicity:** Neither LPG nor LNG is classified as a primary toxic poison. While they can act as simple asphyxiants by displacing oxygen in high concentrations, they do not inherently cause systemic poisoning like carbon monoxide or chlorine gas. * **D) Pressure:** Both LPG and LNG are stored under pressure (especially LPG), and rupture can cause physical damage. However, the pressure itself is a *condition* of storage. The greatest subsequent hazard following a containment failure (driven by pressure release) is the immediate ignition of the resulting highly flammable vapor cloud, making flammability the core hazard.