What if you're exposed to a very loud noise at a very high frequency?

The human auditory system can hear sounds with frequencies no higher than 20,000 Hz and I imagine the threshold for pain is around 120 db. Now, suppose you're exposed to a sound registering at 250 db, and a frequency of 30,000 Hz. Will that cause permanent hearing damage? A noise no one can hear, but can cause mive auditory system damage. Is there anything that create such a noise? Thanks.