As shown in FIG. 1 there is one embodiment of a fumigation apparatus in the form of a module (8) including a panel (10) which can be positioned in or at an opening of an enclosed space in use to define a fumigation chamber. Fumigant inlet means in the form of an orifice (12) are arranged in the panel (10) to allow a flow of a fumigant directly into the fumigation chamber. A nominal number of mixing fans, in this case two fans (16) and (18), thoroughly circulate gases within the fumigation chamber when operating. The module (8) includes a system control box (14) linked to the fumigant delivery orifice (12) and valve system which functions to control the flow of toxic gas into the fumigation chamber. The panel (10), when positioned in use, is secure against the passage of fumigant and gases by means of an inflatable rubber seal (22) which is located around a lip edge perimeter of the panel (10). Extraction means for evacuation of the fumigation chamber gases includes a pipe (28) attached to an orifice (30) located in the lower region of the panel (10), the pipe (28) in turn connected to a contra-rotating fan (34) and an actuated butterfly valve (32) and thence to a pipe exhaust stack (36). Absorption means are operatively coupled to the extraction means on the module (8) to absorb at least part of the fumigant extracted from the fumigation chamber. The absorption means is in the form of a removable absorption bed cartridge (40) and includes activated carbon to which the fumigant attaches or is absorbed and is thus stripped from the gas/fumigant extracted from the fumigation chamber.