Is there a physical limit to how loud a noise can be? As you might imagine, the answer is somewhat complicated, even if you assume normal atmospheric conditions. In video, Benn Jordan discusses a few possible answers, as well as how we should think about the question in the first place. One possible answer is 194 decibels, although experiencing a sound that loud would probably kill you.
See also The World’s Loudest Sound, aka the sound generated by the Krakatoa volcanic eruption in 1883, which Jordan mentions in the video.