Final answer:
In the event of a collapsed bleacher at a college, the immediate actions of the first EMS unit should be to establish a perimeter, assess structural stability, and treat critically injured patients.
Step-by-step explanation:
When the bleacher at a college collapses and you are the first EMS unit to arrive on the scene, your immediate action should be to establish a perimeter to keep bystanders away. This is important to ensure the safety of the responders and prevent further injuries.
After establishing the perimeter, your next immediate action should be to assess the structural stability of the collapsed bleacher. This will help you determine whether it is safe to enter and provide assistance.
Once the structural stability has been assessed and the area is secured, you can then proceed to begin treating the most critically injured patients. Prioritizing the care based on the severity of injuries is essential to provide the necessary medical attention in a timely manner.