The fruit of several years of our colleague Marcin’s work in the form of an article has just been published in an electronic version in the renowned journal Science of the Total Environment. A theoretical model taking into account the most important – from the point of view of historic interiors – physical processes, such as surface roughness and turbulent flow as well as air and surface temperature gradients can be exploited to estimate the rate of soiling of priceless wall paintings, contributing to their better protection.