Pipe Labeling Requirements
ANSI / ASME A13.1
According to ANSI/ASME A13.1, pipe markers should conform to certain requirements. The most recent update to the ANSI/ASME A13.1 code has introduced a new color scheme that specifies which colors to use for pipe labels. The code also specifies standards for the label sizes and placement.
In 2007 the ANSI/ASME A13.1 standard was updated and is now recommended for all new pipe marker applications. For facilities with existing pipe markers, it is recommended that they are updated for consistent identification.
ANSI/ASME A13.1 Standard Label Colors
The current version of the ANSI / ASME code uses a pipe labeling standards color code chart with six standard color combinations, and four user-defined combinations, as shown in the table below. The colors are based on the contents of the pipe; in general, the most hazardous feature of the contents should determine the colors used.
Pipe Contents |
Color Scheme |
| Fire-quenching fluids | White text on red |
| Toxic and corrosive fluids | Black text on orange |
| Flammable fluids | Black text on yellow |
| Combustible fluids | White text on brown |
| Potable, cooling, boiler feed, and other water | White text on green |
| Compressed air | White text on blue |
| User-defined | White text on purple |
| User-defined | Black text on white |
| User-defined | White text on grey |
| User-defined | White text on black |
FREE ANSI/ASME A13.1 - Pipe Marking Guide
Pipe marker labels indicate which pipelines are dangerous, direction of flow, and pipe contents.
Pipe Label Placement
Pipe labels should be positioned so that they can be easily seen from the normal angle of approach—for instance, below the centerline of the pipe if the pipe is overhead, and above the centerline if the pipe is below eye level. Pipe labels should be placed:
- Adjacent to all valves and flanges
- Adjacent to all changes of direction
- On both sides of wall or floor penetrations
- At regular intervals on straight runs (50' is the acceptable maximum spacing, but closer spacing might be necessary for visibility.)
On many piping systems, there will be valves, actuators, and/or transmitters that can be tricky to label with an adhesive pipe marker. Accessories such as Valve Tags and DuraTags can make labeling these awkward places quick and easy.
Label Size
Pipe diameter determines the appropriate label and text sizes, as shown in the following table.
| Outside Pipe Diameter (including insulation) | Minimum Length of Label Color Field | Minimum Letter Height | |||
| Inches | mm | Inches | mm | Inches | mm |
| .75–1.25* | 19–32 | 8 | 203 | .5 | 13 |
| 1.5–2 | 38–51 | 8 | 203 | .75 | 19 |
| 2.5–6 | 64–152 | 12 | 305 | 1.25 | 32 |
| 8–10 | 203–254 | 24 | 610 | 2.5 | 64 |
| >10 | >254 | 32 | 813 | 3.5 | 89 |
Need help with pipe labels? Give us a call at 1-888-326-9244. Our knowledgeable customer service staff will be glad to answer your questions and help find the right labeling solution for your facility.
Get A FREE Facility Pipe Marking Guide




