A13.1 is intended to establish a common system to assist in identification of hazardous materials conveyed in piping systems and their hazards when released in the environment. This scheme concerns identification of contents of piping systems in industrial and power plants. It is also recommended for the identification of piping systems used in commercial and institutional installations, and in buildings used for public assembly. It does not apply to pipes buried in the ground nor to electrical conduits.SPECIAL ORDER. Will take a few extra days to receive. No returns.