What is the explosive range of natural gas?

What is the explosive range of natural gas?

• A. 5% to 15%
• B. 3% to 12%
• C. 8% to 20%
• D. 0.5% to 2%

Answer: (A)

The concept here is the flammable (explosive) range of natural gas in air—the mix of gas and air that can ignite. For natural gas, which is mostly methane, ignition can occur when the gas concentration in air is between about 5% and 15% by volume. Below 5% gas, the mixture is too lean to burn; above 15% gas, there isn’t enough oxygen to sustain combustion. So a concentration within roughly 5%–15% is the sweet spot where a spark or flame could ignite the mixture. That’s why 5% to 15% is the correct range. The other options fall outside these limits: they’re either too lean or too rich to ignite.

The concept here is the flammable (explosive) range of natural gas in air—the mix of gas and air that can ignite. For natural gas, which is mostly methane, ignition can occur when the gas concentration in air is between about 5% and 15% by volume. Below 5% gas, the mixture is too lean to burn; above 15% gas, there isn’t enough oxygen to sustain combustion. So a concentration within roughly 5%–15% is the sweet spot where a spark or flame could ignite the mixture. That’s why 5% to 15% is the correct range. The other options fall outside these limits: they’re either too lean or too rich to ignite.