I lost a nic 1 inch wide by two inch long chunk of skin on my wrist marshalling a sportsman 1/8th race a few years ago. Someone gasses a car in my hand when im not pitting it goes right back on its lid, if you do it twice in a row someone else can marshal your car.
If someone crashes around me with their pipe loose Ill shut them down too, no one wants to hear a nitro motor without a muffler.