The minimum concentration of a combustible substance in a gaseous mixture (typically air) that will support a self-propagating flame upon ignition is a critical safety parameter. Below this concentration, the mixture is considered too lean to burn. For example, if the lower explosive limit of methane is 5%, a mixture containing less than 5% methane in air will not ignite and propagate a flame.
This parameter is crucial for safety in industries that handle flammable materials. Understanding and respecting it prevents explosions and fires, safeguarding lives and property. Historically, incidents involving explosions highlighted the necessity of defining and adhering to these limits, leading to improved safety regulations and engineering practices.
