What is defined as the Upper Explosive Limit (UEL)?

The Upper Explosive Limit (UEL) refers to the maximum concentration of a vapor in the air that can lead to an explosion if an ignition source is present. At this level, there is too much fuel vapor in the air, causing the mixture to be too rich to ignite. If the concentration exceeds this upper limit, there is insufficient oxygen available to support combustion, making the environment safer from explosion hazards. Understanding UEL is crucial for safety practices in environments where volatile substances are present, as it helps in determining safe handling and storage guidelines to prevent explosive incidents.