Abstract: A said suction hood (1) being connected to a gas extraction system (7) and preferably suspended on a movable arm system (4) permitting the suction hood (1) to be set in various positions relative to an area (2) from which the injurious gases (G) are extracted. For substantially increasing the depth of the suction hood when required, the suction hood (1) includes at least one and preferably three movably mounted wall elements (15, 16, 17) which is or are settable in a folded position or folded positions and which is or are unfoldable into a position or positions wherein it or they gives or give the suction hood (1) a fume cupboard like shape and function.

Abstract: An apparatus for filtering contaminated gases. An extraction device provides a slow passage for the gases. The extracton device is in fluid communication with an intake port of a fan aggregation. The fan aggregation provides a vacuum for drawing the gases through the extraction device. The fan aggregation is rigidly supported on top of a filtration container. The gases are expelled by the fan aggregate through an exhaust port and into an interior chamber of the filtration container. A filter blocks the passage of contaminant components of the gases and permits the passage of noncontaminant of the gases from the interior chamber to the atmosphere. A gas-permeable housing surrounds the filter to retain the filter and support the weight of the aggregate.