Copper Tubes for plumbing- Specification has been included in the mandatory ISI Certification Scheme under IS 14810: 2000. This standard covers phosphorized (DHP) copper tubes suitable for general plumbing and similar applications for the conveyance of fluids including water and are commonly used with solder, flared or compression type fittings. The type of copper tube suitable for any particular application is determined by the internal or external fluid pressure in the installation and service condition or any other local requirement.