which is the correct first step when you arrive at a scene where a person has collapsed?

The correct first step when you arrive at a scene where a person has collapsed is to check that the scene is safe before you approach the person.

Quick Scoop

Before doing anything else, take a second or two to scan your surroundings. A collapsing person might be near traffic, live electricity, fire, falling debris, or other dangers. If you get hurt, you cannot help them, and now there are two victims instead of one.

Once the area looks safe, move in quickly, tap the person, and shout to see if they respond, then call emergency services if they do not respond or are not breathing normally.

Simple step sequence

1. Check for danger to yourself, the victim, and bystanders (traffic, fire, wires, unstable structures).

2. If safe, approach, tap their shoulders, and shout “Are you okay?” to check responsiveness.

3. If no response or abnormal breathing, call your local emergency number (e.g., 911) or tell someone specific nearby to call.

4. Follow dispatcher instructions; start chest compressions if they are not breathing normally and you are trained or guided to do so.

In many first aid and CPR courses, this is taught as: Danger → Response → (Shout) for help → Airway → Breathing → CPR , and it always starts with Danger (scene safety).

Bottom line (TL;DR):
First, make sure the environment is safe, then go to the person, check responsiveness, and call for help if they are unresponsive or not breathing normally.

Information gathered from public forums or data available on the internet and portrayed here.