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 (Second Edition, 2021):
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:
| PSI | Bar | Color | |
| 10,000 | 690 | - | Yellow |
| 15,000 | 1,034 | - | Green |
| 20,000 | 1,379 | - | Blue |
| 30,000 | 2,068 | - | Silver |
| 40,000 | 2,758 | - | Orange |
| 55,000 | 3,792 | - | Red |
The color scheme should be easily identifiable at least two feet from both hose ends.
If working between pressures in the chart, the color coding shall meet or exceed the maximum rated output pressure of the unit. If the pressure rating of the hose is in between the values in the chart, the hose shall be color coded to the lower pressure.
Updated May 11, 2021