Which material is NOT typically recognized as a combustible fiber?

Glass wool is not typically recognized as a combustible fiber. This is primarily due to its composition; glass wool is made from fine strands of glass and is treated to be non-combustible. As a result, it does not ignite and burn like natural or organic fibers.

On the other hand, materials such as kapok, rags, and hay are all composed of organic materials that can easily catch fire and sustain combustion. Kapok fibers come from the kapok tree and are highly flammable. Rags, which often consist of fabrics that contain cotton or other combustible materials, can also easily ignite. Similarly, hay, being dried grass, is very combustible. These materials are frequently associated with fire hazards in various settings.

Understanding the properties of these materials is crucial for fire prevention and safety, as recognizing which items are combustible can guide effective risk management strategies in environments that may be susceptible to fire.