What should be the first action in response to a hazardous materials incident?

Isolating the area is the appropriate first action in response to a hazardous materials incident because it serves to protect both responders and civilians from exposure to potentially dangerous substances. By establishing a safety perimeter, emergency personnel can control access to the site, reducing the risk of harm to bystanders and limiting the spread of hazardous materials. This action also allows for a more organized and safe approach for further response efforts.

In addition to ensuring safety, isolating the area provides responders with the time they need to assess the situation before making decisions about evacuation or conducting environmental testing. It creates a buffer that can prevent injury and limit unnecessary exposure, which is critical when dealing with unknown substances. Once the area is secured and isolated, it becomes easier to evaluate the necessary next steps, including notifying local authorities or conducting further assessments.