Our first clue was that there were very few standard household washing machines. Most of them seemed to be four- or six-load-sized heavy-duty washers. All the driers, without exception, were also big heavy-duty machines.
Next, the sign on the wall that read:
We presumed they'd have to be washed in a bucket of gasoline, or something similar, to remove the oil, and then thoroughly air-dried before they'd be allowed in the laundromat's washers to remove the smell of the solvent.
Finally, the sign next to the previous one read:
So that's where the itching sensation comes from!