Pressure Cooker

Based on title, could be politics but isn't. I cook things in a pressure cooker quite often. Two or three times a month probably. I have a routine which never varies. I put the stuff in the pot, put the lid on and light the fire, and then go in the living room and sit down. When the hissing starts I freak out completely, caught entirely by surprise. I am never ready for it and always think something is blowing up somewhere. It usually takes five minutes to get my heart rate below 100.