Which standard test assesses flame spread and smoke development of interior finishes?

• A. NFPA 275
• B. NIST E-84
• C. ASTM E-84
• D. ASTM 255

Answer: (C)

This question is about how interior finishes are evaluated for how quickly flames can spread and how much smoke they produce. The standard method for this is ASTM E-84, known as the Steiner tunnel test. In this test, a small sample of the interior finish is placed in a tunnel and exposed to flame. It measures two key results: the Flame Spread Index (FSI), which indicates how far the fire will travel along the surface, and the Smoke Developed Index (SDI), which indicates how much smoke is produced. Based on these values, finishes are classified (Class A, B, or C) for use in buildings, guiding code requirements and safety decisions. The other options refer to different tests or standards that don’t specifically quantify flame spread and smoke development of interior finishes, so ASTM E-84 is the correct choice.