All three of my cats were in the kitchen today, laying around on our kitchen table, as I was making a batch of chicken soup in our electric pressure cooker. I was thinking maybe I should carry them all into another room before I open the steam valve - which typically scares the crap out of them, and I feel bad for stressing them out like that. But for whatever reason I didn't and just opened the valve when the cooking was done - and two of the three cats jumped several feet in the air and bolted out of the room in terror. Strangely one of our cats, is unfazed by the loud noise and just sat there, looking at the other cats like they were nuts or something. This is about the second or third time I've used the pressure cooker, and released the steam when she was in the room, and she didn't even flinch. I'm almost starting to wonder if perhaps she's deaf, or if she just genuinely is not scared of the device any more. She will take off though when we use stuff like a vacuum cleaner - but I don't know if she's more scared by the vibrations from it, or can actually hear how loud it is. Some other things that freak them out - when I had the SodaStream, it makes a really loud and jarring noise when you press the button on it to carbonate the water. Also, we have an air compressor in our garage which will periodically start up on it's own, and it has a really loud engine. For some reason one or all of them always seem to be walking past the door right when it kicks on, and they all jump up in the air and dart away, lol.