What is an essential part of casualty prep before evacuation?

Applying additional bandages is crucial in casualty prep before evacuation because it helps to control bleeding and protect the injured area from further contamination. Securing the injury site with effective dressings not only aids in stopping the loss of blood but also stabilizes the injury, which is vital for the casualty's condition during transport.

Taking care of wounds and ensuring that they are adequately covered can significantly impact the patient's chances of survival and recovery once they reach more advanced medical care. Proper bandaging can minimize complications such as infections or further hemorrhaging, making it a critical step in the preparation of a casualty for evacuation.

The other options mentioned all play important roles in casualty management, but they don't directly focus on the immediate priority of preparing the casualty for safe transport, which is effectively managing wounds and controlling bleeding through the application of bandages.