Final answer:
After ensuring the scene is safe in an emergency, the first step in the primary assessment is to check for responsiveness. If there is no response, summon EMS personnel and proceed with emergency measures like first aid or CPR.
Step-by-step explanation:
When starting the primary assessment of a victim in an emergency situation, after ensuring the scene is safe, the first step is to check for responsiveness.
This can be done by gently tapping the victim and speaking to them to see if they react. If there is no response, you would then need to call or summon EMS personnel and proceed with further emergency measures, such as opening the victim's airway, checking for breathing and pulse, and administering first aid or CPR if necessary. It is essential to act quickly but calmly, as rapid assessment and action can be critical in such situations.