To a very small critter it would most definitely cause a lot a distress and anxiety .. Just to put it in perspective, compare the scale in terms of size of a hair dryer and the size of your hamster .. Now think about the size YOU are and the size of a hair dryer scaled up to a comparitive size .. It would be deafening and HOT ... NOW think about someone ELSE whom you can not communicate with at the controls .. It would scare the b'jezus outta you.