Pipe Marking Color Code Guide

Pipe Marking Color and Standards

Water Pipe Marker

The contents of a pipe determine the color code used to identify that pipe. There are several standards for labeling pipes, so the color coding may vary based on the type of facility or the pipe contents. However, all of the standards require color coded pipe labels.

ANSI Pipe Color Code

ANSI A13.1 is the pipe color code standard used in most buildings and facilities. It is the type of pipe color coding you'll see almost everywhere.

The ANSI standard specifies the following pipe color code combinations:

Pipe Color Coding In Commercial Buildings and Schools

Often commercial buildings will have a variety of different types of the same substance, all of which need to be identified. For example, commercial buildings often have chilled water, condenser water, domestic water, low-temp hot water return, and high-temperature hot water return. The ANSI standard specifies that all of these pipes be marked with a green pipe marker with white text. But that does not identify the type of water. DuraLabel has published a consensus standard that provides an additional pipe color code using color bands to identify the specific type of water a pipe contains.

Commercial Building Pipe Marking Guide
Free full color, laminated pipe marking guide!

Pipe Color Coding For Ammonia Refrigeration Systems

The pipe color code system specified by the International Institute of Ammonia Refrigeration (IIAR) also uses colored bands, but in this case they identify the physical state and pressure of the ammonia in the pipe.

As specified by IIAR ammonia refrigeration system pipe markers are yellow with black text. If the ammonia is in a liquid state, an orange bar with black lettering is added. If the ammonia is in a vapor state, a blue bar with black lettering is added. If both states are present, the orange and blue bars are used together.

Red and green bars are used to indicate the pressure in the pipe. Red with black lettering indicate high pressure (<70 psig). Green with black lettering indicates a low pressure (>=70 psig).

Ammonia Pipe Marking Guide
Free full color, laminated pipe marking guide!

Pipe Color Coding of Medical Gases

Because of the health risks that can result from using the wrong medical gas, medical gas pipes are color coded using the NFPA 99 and CGA C-9 standards. In this case the color coding provides a more detailed identification of the pipe contents than the ANSI standard provides. The following are some examples of what this standard specifies for medical gas pipe color coding:

There are additional pipe color coding combinations for medical gases.

As you can see, the context in which the pipe is located is important. In one context white lettering on a green background indicates water (ANSI pipe color code). In another context it indicates oxygen (CGA C-9 pipe color code). If you were on a ship then white on green indicates sea water, while white text on blue is the pipe color code for fresh water. Fortunately most pipes are marked using the ANSI pipe color code, and most of us don't frequently move from one type of facility to another. So we can easily become familiar with the pipe color code system we see every day.

Medical Pipe Marking Guide
Free full color, laminated pipe marking guide!

Making Color Coded Pipe Marker Labels

No matter what type of facility you work in, when you need new or replacement pipe markers, the source to turn to is DuraLabel. You can purchase pre-printed pipe markers or get a DuraLabel label printer for making your own pipe markers. DuraLabel has all of the right supplies for quickly and easily making whatever type of color coded pipe marker you need. Call 1-888-326-9244 today and ask about special offers on DuraLabel pipe marking kits. You'll be glad you did.