What term refers to the various components involved in a hazardous materials incident?

The term that best refers to the various components involved in a hazardous materials incident is "Components." This terminology captures the different parts or elements that contribute to the overall scenario of a hazardous material event, including the materials themselves, the reactions they may cause, the environmental factors, and the response strategies that are implemented.

In the context of hazardous materials incidents, understanding the components ensures that responders can effectively manage and mitigate the situation by analyzing interactions between various factors, including human, environmental, and technical resources. Each component plays a crucial role in determining how an incident unfolds and what measures must be taken to address it.

While "quantities," "elements," and "classes" might relate to different aspects of hazardous materials or incidents—such as measuring the amount of a hazardous substance, the fundamental substances from which materials are derived, or the categorization of hazardous materials—they do not collectively encapsulate the full range of factors involved in a hazardous materials incident as effectively as the term "components" does.