What are the lower and upper explosive limits for Acetylene?

Acetylene is a highly flammable gas, and understanding its explosive limits is crucial for safety in environments where it may be present. The lower explosive limit (LEL) of 2.5% indicates the minimum concentration of acetylene in air that can ignite when exposed to an ignition source. The upper explosive limit (UEL) of 81% denotes the maximum safe concentration in air; above this level, the mixture becomes too rich in fuel to ignite.

These limits are critical for safe handling and mitigation of risks in mine rescue operations, especially considering the potential presence of various gases and the impact of their explosive properties. The chosen option correctly states these limits, providing essential information for ensuring safe practices when working with acetylene in confined or potentially hazardous environments.

In contrast, the other options present incorrect values for LEL and UEL, which could mislead individuals in interpreting the hazard level associated with acetylene. Having accurate knowledge of these limits is vital for effective safety measures and emergency responses in any situation involving this gas.