Abstract: A device for microbiologically controlling a dust-laden pressurized gas, including dust collecting device in an inner cavity provided with a gas inlet and a gas outlet and having an internal pressure that is equal to the pressure of said dust-laden gas at least during the operation of said device.

Abstract: A method for closely protecting materials (10) sensitive to contamination by airborne contaminating agents and placed on a work surface (P). At least one decontaminated gas stream (1, 2) is fed from either side towards the materials in a direction substantially parallel to the work surface, and each gas stream (3) leaves the work surface in an intermediate area between the edges of the work surface and in a direction substantially perpendicular thereto. Alternatively, at least one gas stream is fed towards the materials from above the work surface at an intermediate area between the edges thereof, and in a direction substantially perpendicular thereto, and each gas stream leaves the work surface in a direction substantially parallel thereto and on either side of the materials.