What range is defined between the lower flammable limit and upper flammable limit?

The term that correctly describes the range between the lower flammable limit (LFL) and the upper flammable limit (UFL) is the flammable (explosive) range. This range indicates the concentrations of a combustible gas or vapor in air that can ignite and produce a fire or explosion when an ignition source is present. Understanding this range is crucial for fire safety because it helps firefighters and safety personnel identify the conditions under which a fire hazard exists.

The flammable range is specific and reflects the concentrations that are too rich (above the UFL) or too lean (below the LFL) for combustion to occur. Operating within this range is necessary to ensure that fire safety protocols are effectively evaluated to prevent incidents.

The other options, while related to combustion and fire behavior, do not accurately describe this specific phenomenon. The ignition range may refer to conditions necessary for ignition but does not define the limits of concentration. The temperature range does not relate to concentration limits but instead deals with thermal factors influencing ignition. The combustion range could imply a broader understanding of combustion beyond concentration limits, which is not as precise as the flammable range.