What is a disadvantage of LPG compared to CNG?

The correct choice highlights a critical safety consideration when comparing LPG (Liquefied Petroleum Gas) to CNG (Compressed Natural Gas). LPG can pose a higher risk of flammability primarily due to its vapor density. When released, LPG vapor is heavier than air, allowing it to accumulate in low-lying areas, which increases the likelihood of ignition if an ignition source is present. This characteristic necessitates careful handling and storage practices to mitigate the risks associated with potential leaks and subsequent fire hazards.

In contrast, CNG is lighter than air and dissipates quickly into the atmosphere if released, generally reducing flammability risks in open environments. Understanding this distinction is vital for ensuring safe operations involving the use of these gases as fuel.