What is described is a cleanroom arrangement with a housing that separates from the surroundings a space which immediately or indirectly adjoins a floor region, with a mobile filter-ventilator unit which has an air inlet region and an air outlet region and is arranged in the surroundings outside the space, and with a supply line connecting the air outlet region and the space bounded by the housing. The invention is characterized in that the housing is a tent-like shell wall arrangement which encloses the space in a dome-like and uninterrupted fashion and which comprises a flexible, folding shell wall that directly faces the space and is made exclusively of at least one cleanroom-compatible material and comprises at least one support element that rests on the floor region and/or at least one hanging arrangement provided on the shell wall; in that the at least one cleanroom-compatible material is suitable for directly bounding a cleanroom of ISO classes 1 to 9 according to DIN ISO/FDIS 14644-1:2015-08; in that the shell wall is spaced apart from the floor region at least in certain sections, or provides, indirectly or directly adjoining the floor region, at least one opening in the shell wall or at least one shell wall section with a higher air permeability than in the rest of the shell wall, for the controlled outflow of air from the space region into the surroundings; and in that the mobile filter-ventilator unit is designed to provide, from ambient air, ultrapure air in accordance with the above standard, and the supply line is produced as a hollow duct made of cleanroom-compatible material in accordance with the above standard, which discharges into the space at an upper shell wall region so as to establish, within the space, a vertical, downward-oriented flow of pure air which exits the space in a controlled manner close to the floor region.