In what range do gasoline vapors mix with air to form explosive mixtures?

In what range do gasoline vapors mix with air to form explosive mixtures?

• A. 0.1% to 1%
• B. 5% to 15%
• C. 1% to 8%
• D. 10% to 20%

Answer: (C)

The idea being tested is the flammable range of gasoline vapors in air—the window where a mixture can ignite or explode if an ignition source is present. This range is defined by the lower and upper flammable limits: below the lower limit the mixture is too lean to burn, and above the upper limit it’s too rich to sustain combustion. For gasoline, that practical range is about 1% to 8% vapor by volume in air. Within this window, ignition can occur; outside of it, ignition is not possible under normal conditions. Real-world factors like temperature, pressure, and exact fuel composition can shift these numbers a bit, but 1% to 8% is the standard safety-relevant range to remember.

The idea being tested is the flammable range of gasoline vapors in air—the window where a mixture can ignite or explode if an ignition source is present. This range is defined by the lower and upper flammable limits: below the lower limit the mixture is too lean to burn, and above the upper limit it’s too rich to sustain combustion. For gasoline, that practical range is about 1% to 8% vapor by volume in air. Within this window, ignition can occur; outside of it, ignition is not possible under normal conditions. Real-world factors like temperature, pressure, and exact fuel composition can shift these numbers a bit, but 1% to 8% is the standard safety-relevant range to remember.