What is the ASTM E 84 and UL 94?

 

1. ASTM E 84:
This standard is also known as the "Standard Test Method for Surface Burning Characteristics of Building Materials" or the "Steiner Tunnel Test." It is used to measure the flame spread and smoke generation of materials such as wall and ceiling finishes, insulation, and other interior finish materials. The test involves exposing a specimen of the material to a controlled flame ignition source while measuring flame spread and smoke density.

 

 

- Flame Spread Index (FSI): It quantifies the rate at which flame spreads across the material's surface. Lower FSI values indicate better fire resistance.

- Smoke Developed Index (SDI): It measures the amount of smoke generated during combustion. Lower SDI values indicate reduced smoke production.

 

2. UL 94:
This standard is issued by Underwriters Laboratories (UL) and specifically focuses on the flammability of plastic materials used in various applications. UL 94 categorizes materials into different classifications based on their burning behavior and the extent to which they self-extinguish after being ignited.

 

 

- Ignition resistance: The material's ability to resist ignition when exposed to a small flame.

- Flame propagation: The material's ability to prevent the flame from spreading vertically.

- Dripping: Whether and how much material drips or falls during burning.

- Self-extinguishing: The material's ability to stop burning after the ignition source is removed.

 

UL 94 classifies materials into different ratings, such as V-0, V-1, V-2, HB, and others, each representing varying levels of flammability and self-extinguishing capabilities.

 

Both ASTM E 84 and UL 94 tests are widely used to assess fire safety and flammability characteristics of materials, helping manufacturers and regulatory bodies determine their suitability for different applications.