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Pipe Color Code

By Brian McFadden

pipe color example

Pipes are a simple, easy, and economical way to move fluids wherever they need to go. In most cases, though, it’s impossible to know the contents of a pipe (or the hazards they represent) from the pipe’s external appearance. For a facility to operate efficiently and safely, it needs a quick and reliable way for workers to identify pipe contents and potential hazards.

Color coding is among the most effective ways to quickly communicate information, and color-coded pipe markers are a common solution to the problem of confusing pipe systems. Most of the standards that discuss pipe labels require a color code; the trick is finding the right code for your needs. With the variety of approaches, how do you know which color code to use for your pipes?

This article will explain the different codes and standards to help you find the best solution for your needs, and direct you to free resources for the color code you choose.

General Purpose Pipe Labels: ANSI/ASME A13.1

Reference chart for ANSI/ASME A13.1 pipe labelingThe single most common pipe labeling standard in the United States is ANSI/ASME A13.1, which describes general requirements for pipe marking and includes a categorized color scheme. OSHA requires a few specific industries to follow this standard, and using it is good practice in most cases where a more specific standard isn’t available.

ANSI/ASME A13.1 assigns colors to pipe labels based on the major hazard or the general application of the pipe’s contents. For example, piping systems that are part of a fire protection system will be marked with red labels and white text; pipes carrying corrosive or toxic materials will be marked with orange labels and black text.

For facilities using this popular standard, Graphic Products offers a free downloadable chart for ANSI/ASME compliant pipe marking.

Water Treatment Piping: Ten States Standards

Reference chart for water treatment pipe markingWhile the general approach in the ANSI/ASME standard works well for many facilities, some industries and applications need a more detailed color code. Water and wastewater treatment facilities, for example, may have miles of pipes that carry “water” — but the difference between clean, potable water and raw sewage is important! Instead of labeling all pipes the same way, these facilities typically follow a more customized color code for their pipe marking.

There are many different codes used in this industry, with local regulation sometimes requiring one or another. The most popular standard for water plants is from the Great Lakes and Upper Mississippi River Board, a consortium of industry experts. They created the 10 States Standards for water and wastewater treatment facilities.

For more information on this standard and its color code, download this free Water Treatment Pipe Marking Guide.

Ammonia Refrigeration Systems: IIAR Bulletin No. 114

Reference chart for ammonia refrigeration pipe labelingSome systems are extremely specialized, with virtually all their pipes carrying the same material. Even in these cases, color coding has a place. For example, the International Institute for Ammonia Refrigeration (IIAR) has a standard for labeling the pipes in ammonia-based refrigeration systems; the main label color (orange) matches the ANSI/ASME recommendation for ammonia, but additional bands of color are used to indicate whether the pipe carries liquid ammonia, vapor, or both, as well as whether the pipe is at a high or low pressure.

The IIAR standard is described in IIAR Bulletin No. 114, and also in this free reference for ammonia pipe marking.

Medical Facility Pipe Marking: NFPA 99

Reference chart for medical pipe markingIn some cases, a standard has been developed naturally in one industry, and then adopted and expanded in another industry. This is the case with the NFPA 99 requirements for pipe marking in healthcare facilities.

Suppliers of compressed air and pure gases marked their containers according to an industry standard, codified in the Compressed Gas Association’s CGA C-9 standard. Hospitals and other healthcare facilities using these compressed gas canisters then extended the same color code to the pipes in their facilities, and added to the code to meet their additional needs. Eventually, this was included into the NFPA 99 standard for healthcare facilities.

For help implementing and understanding the medical pipe marking requirements, see this free guide to NFPA 99 and CGA C-9 pipe color codes.

Pipe Marking at Sea: ISO 14726

Reference chart for marine pipe color codingWhile printed text on a pipe marker is an effective way to provide detailed information, beyond what’s easily achieved with color coding, it has one pitfall: words are limited by language. For ships at sea, or for offshore facilities, there may be a multinational crew at work—or an international rescue team. How can you ensure clear pipe identification, even without relying on text?

The International Organization for Standardization (ISO) has created a standard pipe marking color code for this exact purpose. The ISO 14726 standard uses large labels of a solid color to indicate the general type of pipe system, and adds smaller bands of color to identify the specific contents of the pipe, according to a consistent scheme. This advanced color code gives a workaround for the problem of language barriers and is well-suited to the needs of marine facilities.

Graphic Products offers a free guide to the ISO 14726 marine pipe color code.

Custom Color Codes for Pipe Marking

In many cases, none of the available standards will be a perfect fit for a given facility. The ANSI/ASME standard actually allows for a lot of customization, including several user-defined color combinations, and the standard’s well-recognized color code is only a recommendation. You can build a compliant color code of your own, if that suits the needs of your facility.

Creating a custom pipe marking scheme can be complex, though, and you’ll want to do your research first. Graphic Products’ Best Practice Guide to Pipe Marking covers the major points of all these industry standards, as well as giving guidance on creating your own color code. When you’re ready to label your pipes, consider the DuraLabel line of printers and supplies by Graphic Products to create your custom pipe markers.

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