What is the first step a responder should take when arriving at a HazMat incident?

The first step a responder should take upon arriving at a HazMat incident is to conduct a scene size-up and hazard assessment. This preliminary action is crucial because it allows the responder to evaluate the overall situation, identify potential hazards, determine the nature of the incident, and assess the risks involved. By understanding the scene, the responder can make informed decisions regarding safety measures for themselves and others, including other responders, civilians, and the environment.

A proper scene size-up includes looking for markers of danger such as leaking chemicals, the presence of protective gear, and signs of any serious threat to life or property. This assessment is fundamental for establishing a safe operational area where necessary procedures can be safely implemented.

In contrast, the other options, such as calling for backup, evacuating the area, or setting up a command post, are actions that may follow the size-up but should not precede it. Without a thorough evaluation of the scene, making those subsequent decisions may not be based on accurate information about the specific risks or hazards present. Prioritizing the scene assessment sets the stage for a structured and effective response to the incident.