When approaching an unknown casualty; what is the best way to check for response?

When approaching an unknown casualty, follow these steps to check for a response:

1. Ensure Safety: First, make sure the area is safe for both you and the casualty.

2. Call Out: Stand a safe distance from the casualty and ask loudly if they are okay. This is to see if they respond to sound.

3. Approach: If there is no response, approach the casualty and gently tap their shoulder and ask again if they are okay. This is to see if they respond to touch.

4. Check for Normal Breathing: If there is still no response, check if they are breathing normally. Look for regular chest movements, listen for breath sounds, and feel for breath on your cheek.

5. Call for Help: If the casualty is unresponsive and not breathing, call for medical help immediately and start performing CPR.

Remember, do not put yourself in danger while checking for a response. If the situation is unsafe, call for professional help immediately.