Gas Fitter Practice Test

What is the explosion limits for natural gas?

1. 2.4 to 9.5%

2. 1.9 to 8.5%

3. 4 to 15%

4. 5 to 10%

The correct answer is: 4 to 15%

Natural gas has an explosion or flammability limit defined as the range of concentrations in air that can lead to combustion if ignited. The correct range is 4% to 15% by volume in air. This means that if the concentration of natural gas in the air is below 4%, it is too lean to ignite; conversely, if it exceeds 15%, it is too rich to ignite. Understanding these limits is crucial for safety in the handling and use of natural gas, as it helps in identifying safe operating conditions and preventing explosive atmospheres.