ISO 14726-2 specifies additional colours to be used with the main colours given in ISO 14726-1 for marking of piping systems in accordance with the content and/or function on board ships and marine structures. Additional colours may not be used if no differentiation of a single main colour on board is needed. ISO 14726-2 does not apply to piping systems for medical gases, industrial gases and cargos. It gives no definitions for the listed media and/or functions. These additional colours may also be used, together with the main colours, for piping systems on drawings and diagrams.