What would you do? The Case of the Man and Passing Gas

What would you do?  

So I'm tutoring at the public library.  The public library offers many great perks.  It's relatively quiet, there's usually a lot of space, and it's safe.  On the other hand, the public library offers sanctuary to all sorts of people.  In our largest library, many homeless individuals seek refuge from the weather, use the bathrooms, and read books.  As an individual patron, this doesn't bother me.  As a tutor with a minor, however...well that's another question.  But the homeless population has never been an issue for me and my clients.  I'm not sure why I'm ranting on about it.

When I'm with my clients, I keep them next to me all the time if they're under age.  I escort them to the restroom and wait for them to come out.  It gets kind of difficult when I have to leave my iPad and laptop on the table while my client uses the restroom.  Probably, the weirdest thing I've seen was a man coming out of the elevator with a batting helmet, life vest, and a huge cart full of random things.  Even my client was shocked.

Anyways, back to my original topic:  At the table next to us, there was an older gentleman (gentleman is hardly the word) that kept "passing gas".  It was more loud than anything, no smell.  So a couple questions for you out there...

1.  Has this happened to you?
2.  How would you respond to this situation?

Let me know what you think or have experienced!