WJTA's color coding scheme was added to the Recommended Practices for the Use of High Pressure Waterjetting Equipment in September 2011. The text of the recommendation appears below, excerpted from the current Industry Best Practices for the Use of High Pressure Waterjetting Equipment (First Edition, 2016):
Pressure hoses are designed for various pressures and could present a safety hazard if not used for the designated pressure. In order to better identify the pressure in use, it is recommended that the following color code scheme is used for the applicable maximum working pressure:
The color scheme should be easily identifiable at least two feet from both hose ends. January 1, 2013, is the effective date for implementation.
If working between pressures in the chart, ensure that all hoses are color coded to indicate the higher maximum rated pressure above the intended working pressure. For example, if the desired working pressure is 12,000 psi, use a hose rated at the next highest pressure.