[Sediments on the inner surfaces of the tube of spray-mist suction devices].

Spray mist suction tubes made of polyvinylchloride were examined. Qualitative and quantitative germ determinations of the tube inner surfaces were carried out. To make reproducible examinations a standardized method of germ determination was introduces. Macroscopical model tests, assessments by scanning electron microscopy and chemical analyses dealt with the genesis of the deposits and bacterial coatings in the inner tube. A method has been found which minimizes coating formation by spraying of a contaminating cleaning agent.