A portable cooler assembly comprises a base and a collapsible container defining a cooler. The point of integration of the ammonium sulphate production in the urea production process is chosen according to the desired product composition. Preferably the first responders can view not only the emergency caller’s information for those E911 calls that they are responding to, but also information about other emergency callers that other first responders are responding to. The invention applies mainly to the braking industry. The respiratory conduit includes at least two volumes, wherein one volume is positioned between a first air flow control device and a second air flow control device and another volume is positioned between a second air flow control device and a third air flow control device.