While erasing stuff written using a chalk on a blackboard, with a duster, it is commonly observed that a lot of chalkdust is released in to the air, some part of which is inhaled (largely) by the teacher, and sometimes, also the first/second row students. This can be a problem, since even if we discount the case of bad allergies from chalk-dust, this inhalation can cause coughing etc. which one would ideally want to avoid.
What is the best hack to ensure you inhale as little of chalk-dust as possible during this process?
(Of course, this problem does not apply to the relatively swankier marker-whiteboard version of the same, but that's not what this question is about.)
Here are a few hacks I seem to think off, but none of these is of the creative variety that one would ideally want as an ingenious solution to the problem:
Switch to a classroom with a marker-whiteboard arrangement. (Least creative resort, this isn't what I'm asking about here. This changes the condition of the question.)
Adopt "non-dust" chalk. (Doable, but still not the creative answer I'm anticipating.)
Turn up earlier than the class timings, and wipe the blackboard with a wet cloth, which would reduce the amount of chalk dust inherently existing on the board, even without you having written something. (This is doable, e.g. for the first class of the day. But when multiple classes cascade, i.e. one after another during the day, this is time-costly option, and hence, not very efficient.)
Go outside the classroom, and bump the duster on a flat surface, which would eliminate most of the dust it has procured from earlier, and hence, you are working with a lesser amount of chalkdust.
Tie a handkerchief on your nose and mouth while erasing it, to reduce the amount inhaled. (Perhaps the worst option, I mean, seriously ...!!!)
Is there any simpler strategy (i.e. lifehack) around this problem?