Abstract: The foam generator apparatus includes a pair of collapsible bladders for storing a unitary or binary fluid/foam concentrate mixture and an air bottle forming a source of pressurized gas. These elements are mounted on a chassis which has a proportioning pump, mounted on the chassis, connected to the air bottle, and powered by the pressurized gas, for producing a flow of the unitary or binary fluid/foam concentrate mixture from the pair of collapsible bladders to an output port, wherein the chassis includes two sides pivotally attached to a backplate and operable to form an enclosure around the pair of collapsible bladders. An air-injection apparatus is connected to the output port of the pump to mix a controllable volume of pressurized gas into the fluid/foam concentrate mixture received from the pump to create a foam.