Classroom Etiquette

Every semester I get an email forwarded to me about classroom etiquette. The bulk of the email is just common sense:

Just a reminder that classrooms should be cleaned up at the end of each class in preparation for the next class.
Please ensure that all desks with their chairs are replaced in the proper rows, any additional equipment being used is returned to its original location and when necessary remove any writing from the chalk or dry erase boards.

I actually don't mind erasing chalkboards as long as it's just a small piece, though when someone covers all 4 (or 6) and then doesn't erase, that gets onerous. And it would be nice if there was actually a mention of not shutting down the computer but logging off instead, since the entire start-up routine for the classroom computers is slow and can often take the bulk of the 10 minutes between classes.

But there's one thing the email doesn't address that I wish it could. I don't see how it could do so politely, but what's bothered me most in my teaching, more so than chalkboards, desks and computers, is lingering odours when I take over a classroom.

There have been at least three semesters over the last nine years where I have entered a classroom that smelled unpleasantly of body odour, at least at the front of the classroom (I don't think it's a coincidence that these classes have also tended to be ones that left chalk unerased on the board.) It usually dissipates after the first 10 or 15 minutes, but those first breaths as I set up for class have sometimes been downright awful.

I don't see much of a solution other than plugging my nose, and I'm not advocating that the semesterly email include a line about personal hygiene, but the contamination problem is just as vexing as erasing four boards of calculus equations. Just sayin'.