Which of the following is true regarding the lower explosive limit (LEL)?

The lower explosive limit (LEL) refers to the lowest concentration of a vapor or gas in air that can ignite or explode if an ignition source is present. When considering the truth of the statement that it ensures safety by maintaining vapor below a threshold, it emphasizes that safety practices in laboratory settings aim to keep hazardous vapors below the LEL to prevent the risk of combustion. By maintaining concentrations below this threshold, laboratories can avert potential ignition and explosive situations.

This contextual understanding highlights the critical role of the LEL in risk management regarding flammable gases. Monitoring LEL levels allows safety personnel to implement precautions and engineer controls that keep environments safe from accidents related to flammable vapors.