I recommend you use the term "Black Paticulate Matter" or "Black Matter". This is a growing area of law and these terms are the ones being used in court. What you are saying is, the stuff is identifiable visually by color and that it appears to be loose or easily removed in the case of BPM. Not all mold can be removed hence the BM term while "soot" or most things mistaken for "soot" are loose and can be wiped off.

You could state that based upon other evidence such as moisture or the odor, you suspect mold or WDO or whatever term you're using for mold these days and that you recommend it be followed up. You don't have to be the sole determiner of who problems get referred to. Your primary job is to point them out. The main idea to communicate is there is stuff there you suspect shouldn't be there, you think it in and of itself could represent a problem but also what lead to it getting there as you feel it is not a natural phenomenon to be expected like frost on single pane windows in winter.

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disgusted with some people on this forum. Out of here!