THIS PART OF ISO 7203 SPEIFIES THE ESSENTIAL PROPERTIES and performance of liquid foam concentrates used to make low expansion foams for the control extinction and inhibition of fires of water-immiscible liquids. Minimum performance on certain test fires is specified. The foams are suitable for top application to fires of water-immiscible liquids. Those which will also comply with ISO 7203-3: Fire Extinguishing Media – Foam Concentrates – Part 3: Specifications for Low Expansion Foam Concentrates for Top Application to Water-Miscible Liquids, which is being prepared, will also be suitable for top application to fires of water-miscible liquids. The foam concentrates might be suitable for use in non-aspirating sprayers or for subsurface application to liquid fires, but requirements specific to those applications are not included in this part of ISO 7203