What measure assesses the concentration of smoke emitted by a material when it burns?

The measure that assesses the concentration of smoke emitted by a material when it burns is the Smoke-Developed Index (SDI). This index specifically evaluates the amount of smoke produced by a material under controlled fire conditions, which is crucial for understanding fire safety in building design and material selection.

The Smoke-Developed Index is particularly important in life safety scenarios, as excessive smoke can pose significant hazards to occupants during a fire, obscuring visibility and potentially leading to harmful smoke inhalation. By quantifying smoke production, the SDI helps architects and engineers select materials that minimize smoke generation, enhancing overall safety within a building.

The other options focus on different aspects of fire safety and emission assessments. The Fire Safety Index evaluates the overall fire safety of a building but does not specifically measure smoke concentration. The Combustion Emission Index is more concerned with the various harmful emissions produced during combustion, rather than just smoke. Lastly, the Heat Release Rate measures the energy output of a fire, which, while related to fire behavior, does not directly assess smoke emission.