I'm a stealthy kind of person. Never smoked and no lung conditions so my breathing is pretty much silent. I move elegantly across the planet like a mountain goat, again, making no sound. I'm also no Nick Knowles: I'm a bit on the shy side and rarely dramatically burst into a room causing a loud kerfuffle. All this means I often enter a place already occupied by a fellow human who has no idea I'm there. Then it's only a matter of time before they realise and scream. It happens a lot.
What can I do when I'm in the room? Quickly saying "don't scream" seems like exactly the wrong thing to say.