It is standard training for a PPL that if you are lost and can not resolve your position that you contact 121.5 (well it was when I used to instruct all those years ago and used to ask DnD for a practice PAN with all my students).
This is standard and I think should remain so.
I found it very irritating the other night, couple for Germans or Dutch (I am not a good linguist) were chatting for ages on 121.5. I know that it wasn't an emergency as they were blowing raspberries at each other.
Just out of interest why is it called "Guard"?