Red blood cells are found in blood vessels!
A prepare before the meeting
Fire drills and earthquake drills also have an emergency number like 911 and closest family members phone number
You don't really see what type of dangerous situation but since you asked a dangerous situation you could do is a stunt motorcycle guy that rides his motorcycle over a pool of sharks. Or a man who wears red in a Bulls arena to get the balls attention but he risk dying if he gets punctured by one of the bulls horns. Or another dangerous situation could be someone entering a monster cave. Or another dangerous situation could be someone meeting up with a Stranger online. There's just so many situations