The black hole will never know — sound can't travel in space. (keckobservatory.org)
For smaller vehicles traveling in these spaces, it can become quite dangerous, especially if the driver fails to use appropriate care when making lane changes or turning. (bwglaw.com)
In other words, anyone traveling in the space beside or behind a truck's mirror view is in a blind spot and presents a safety hazard. (texasdrivesafe.com)