What is the upper limit of explosive range for Methane?

The upper limit of the explosive range for methane is indeed around 15%. Methane, which is primarily found in coal mines and can pose significant risks in underground environments, has a flammable range in the atmosphere between approximately 5% and 15% by volume. This means that if the concentration of methane exceeds 15%, it becomes too rich to ignite, as there is insufficient oxygen available for combustion. Understanding this threshold is critical for ensuring safety in mining operations, as the presence of methane in concentrations within this range can lead to explosive environments. Knowledge of the upper limit helps mine rescue teams identify hazardous situations and implement appropriate safety measures to mitigate risks associated with methane.