What is the danger of materials such as bolts of cloths or bales of rags?

The concern regarding materials like bolts of cloth or bales of rags primarily relates to their potential to smolder for long periods of time. When such materials ignite, the fabric can create a smoldering type of fire that is difficult to detect and extinguish. This smoldering phase can generate significant heat and eventually flare up, leading to rapid fire development.

Options focusing on water absorption or oil soaking are less relevant in terms of immediate fire danger with these materials. While fabrics might absorb water, this characteristic doesn't contribute to the primary danger posed during a fire situation. Soaking in oil can enhance flammability, but it is not a characteristic applicable to all types of fabrics. Additionally, the concern about open flames and radiated heat is more associated with materials that burn very quickly or are highly combustible in nature, which doesn't reflect the main risk associated with cloths or rags. Thus, the danger lies notably in their ability to smolder and persist as a hidden fire threat if not properly managed.