3 If, as indicated in paragraph 2 of Annex III of the Directive, a substance is identified in Part I as an “. . . acid, salt” and has salts of one or more of the following names (that is to say, salts of aluminium, ammonium, calcium, iron, magnesium, potassium, sodium or zinc), then the free acid corresponding to that substance is not treated as included in the specification of that substance.