What is a secondary action of investigators after ensuring safety during a Toxic Gas casualty?

In the context of a Toxic Gas casualty, after ensuring safety, the secondary action of investigators typically involves continuing rounds to monitor the area. Monitoring is crucial because it allows investigators to assess the environment for any changes in gas concentration, the effectiveness of ventilation, or the emergence of new hazards. By maintaining vigilance in monitoring, investigators can gather important data that informs further actions. It is essential to ensure that the situation remains stable and that no new dangers arise, as toxic gas incidents can be dynamic and change rapidly.

Collecting samples, searching for leaks, and implementing lockdown procedures may also be important actions but are typically initiated after the immediate monitoring and safety checks have been completed. These actions are more specific and may depend on the situation's status as determined through ongoing monitoring. Therefore, ensuring a continuous assessment of the area is the most immediate and crucial secondary action post-safety confirmation.