How to act in case of an Emergency

Do you know how to act in case you've witness an emergency? Like you've seen someone collapse. I want to share this to everyone just in case you've encounter such situation in your workplace or in your home.
In case of an emergency the best thing you must put in mind is "DON'T PANIC", be calm and assess the situation.
If you see a victim collapse the first thing you must do is:

1. First assess the situation around you. Is it chaotic, hostile or dangerous.
2. Call for help or call your local emergency alert number, like 911.
3. Assess the victim's response. Is he responding to your voice, your tap or no response at all.
3. If the victim is responding to your voice or your tap ask him the problem and assure him of your presence and assistance.
4. If the victim is not responding to any stimulus. Assess the airway if it is patent or there is no visible obstruction in the mouth, if there is any and you can see it try removing it by hand sweeping. Then try to grab the head and the chin and push them up in synchrony as if you try to let the victim look up, but do it lightly.
5. Assess the victim if he is breathing or not by moving your head close to him look for the chest if rising, listen if there is a breathing noise and feel if there is an air rushing out and in.
6. If you don't see all this things place your hands one over the other in the center of the victim's chest and push hard 1 1/2inch for a cycle of 15 compression and then give the victim a two breath and repeat the cycle again, until the ambulance and medic arrive.
By this you can save lives and prevent the further deterioration of the victim's condition.