OHST Practice Exam

What factors govern the chance of a dust cloud igniting?

1. Oxygen content and dust accumulation

2. Size of dust particles and impurities present

3. Strength of the source of ignition

4. All of the above

The correct answer is: All of the above

In assessing the potential for a dust cloud to ignite, it's essential to consider multiple contributing factors that interact to influence ignition risk. The chance of ignition depends on a combination of the oxygen content in the environment, the accumulation of dust, the size and characteristics of the dust particles, and the strength of the ignition source. The oxygen content is crucial because sufficient oxygen is required to support combustion. Higher oxygen levels can increase the likelihood of a dust cloud igniting. Similarly, the accumulation of dust can create a more dense cloud, enhancing the possibility of ignition by increasing the available combustible material. The size of dust particles is another important factor. Smaller particles tend to have a larger surface area relative to their volume, allowing them to ignite more easily when suspended in air compared to larger particles. Impurities in the dust may also influence its ignition properties, either by making it more combustible or by creating byproducts that affect ignition characteristics. Finally, the strength of the ignition source plays a significant role. This may include heat, sparks, or flames, and stronger sources increase the chances of overcoming the energy barrier needed for ignition. Considering all these aspects, the correct answer comprehensively encompasses the various factors involved in the ignition of a dust cloud, demonstrating that the interaction of