Judging tendency for soiling of visible surfaces near air ducts

摘要

Arrangement for the appraisal of the tendency of surfaces near air discharge openings to be soiled is claimed, in which an accelerated simulation determines the tendency for small or large (as defined by their inertia) particles to be deposited. The simulation with small particles leads to a chemical reaction on the test surface which results in discoloration whilst large particles are deposited as dirt on surfaces of contrasting colour.