$299.00 until  Free Shipping*
  • Quick Order
  • Contact Us
  • Resource Center
  • My Account

Pipe Marking Guidelines

Click here for printable version.

Several Laws and Regulations exist regarding Pipe Markers and Valve Tags. Most prominent of them are the Occupational Safety and Health Act or OSHA Act of 1970, and the Federal Mine Safety and Health Act of 1977. Click here to shop for Pipe Markers and Valve Tags.


ANSI/ASME A13.1 is the pipe identification standard most commonly used in the United States. The standard specifies the primary and secondary means of identifying pipe contents, as well as the size, color and placement of the identification device.


The text legend (name of pipe content) and directional arrow remain the primary means of identifying pipe contents. Attaching arrows at one or both ends of the marker indicates flow direction. See the ANSI/ASME size chart and installation guide in the following sections for more details.


A secondary means of pipe marker identification is the color code of the marker. The terminology of inherently hazardous or nonhazardous has been removed from the standard, effective since 2007. The combination of Yellow/Black is now assigned to flammable fluids and oxidizing fluids while Green/White pipe markers identify potable, cooling, boiler feed and other water-related substances. These updates mean that legends such as hot water, cold water and steam will now use the color code of Green/White. Seton still offers many Yellow/Black pipe markers for these contents from many our top-selling brands as well.

Other significant color changes in 2007 included the addition of Brown/White for combustible fluids and Orange/Black for toxic or corrosive fluids. The fact that the standard has identified specific colors for flammable liquids, combustible fluids and toxic or corrosive fluids means Safety Data Sheets should be consulted before selecting a color. Further, if the pipe being labeled contains multiple hazards -- like flammable and toxic -- determining which poses the greater hazardous risk is vital and should dictate the way in which your pipe is marked. If chilled or heating systems contain toxic treatments, for example, the color combination should be Orange/Black.

The 2007 standard also identified four additional “defined by user” color combinations for additional customization options on non-standard markers. Those exact colors are the recommended safety colors contained in the ANSI Z535.1 standard.

The updates to ANSI/ASME A13.1 added oxidizing fluids to the definitions for Yellow/Black, but did not add any new colors to the standard.

Installation Guide


Seton Pipe Marking Systems Meet the ASME(ANSI) A13.1-2015 Standard

According to the standard, pipe markers should be positioned so that they are readily visible to plant personnel from the point of normal approach. Seton pipe markers instantly tell you all you need to know about pipe contents, direction of flow and whether they’re hazardous or safe.



How to Properly Label Pipes

1. Obtain a legend list of all pipe contents in your plant.

2. Collect the following data on your piping systems (this may require tracing lines to determine quantities and sizes):

– Pipe contents

– Outside diameter of pipe (including insulation)

– Quantity of markers needed per ASME/ANSI A13.1 or other standards

– Pressure

– Temperature

– To/From information

– Location of specific legends by area (for aid in installation)

***Note: You may be able to use blueprints or P&IDs if they are current instead of walking down all of your lines. Seton also offers Take-Off Services to help you determine your pipe marking needs.

3. Select color of marker.


Choose The Right...



Seton pipe marking systems meet ANSI/ASME size recommendations.

The A13.1-2015 standard also makes recommendations as to the size of letter height and length of color field for various pipe diameters. These recommendations are shown in the table below. Seton markers, when used properly with arrows and banding tape or arrow tape, meet or exceed the standard.





Seton Pipe Marking Systems Meet ASME(ANSI) Color Recommendations: Unmarked pipes mean danger to both life and property. Numerous injuries have occurred through ignorance of pipe contents, particularly when outside agencies are called in under emergency conditions.


Color with Definitions


Over 150 stock legends available! Still can't find the wording you need? No problem, we can customize markers to your exact wording.




Communicate hazard information with your Pipe Markers through GHS Pictograms. ASME A13.1 2015 incorporated GHS pictograms into the 2015 revision, recommending their use as part of the legend. A corresponding piping label may be provided with pipes connected to containers labeled in accordance with GHS requirements. The corresponding label should contain at least the product name or identifier, the pictogram, the signal word and the physical, health and environmental hazard statement(s).

GHS Pictogram

*The applicable GHS pictogram as illustrated may be included as part of the legend. GHS Pictograms available for select Pipe Markers only.

For more information on the ANSI/ASME A13.1-2015 Standard, please visit the following the American National Standards Institute online at: https://www.asme.org/products/codes-standards/a131-2015-scheme-identification-piping-systems-(1)



Shop All Pipe Markers

We use cookies on this site to enhance your user experience. Close