Which hazard is NOT listed as a mechanism of harm for first responders?

Psychological hazards are not typically classified as a mechanism of harm for first responders in the same way that the other options are. When assessing hazards, the focus is often on physical and chemical threats that can cause immediate harm.

Thermal hazards, such as burns from fires, involve exposure to excessive heat or flames. Chemical exposure relates to various substances that can be harmful upon contact or ingestion. Biological hazards refer to pathogens or contaminants that can lead to illness. These three categories represent tangible risks that first responders may face in their line of duty.

While psychological hazards are a genuine concern in the context of first responder well-being—given the stress and trauma they may experience—they do not fall under the same category of immediate physical mechanisms of harm, thus distinguishing them from the others in this specific context.