The APWA Color Code: A Guide to Underground Utility Markings

Image of 3 blue marking flags with the caption "a guide to the utility color code"

Ensuring safety on construction sites involves meticulous attention to detail, one of the key aspects of ensuring safety on job sites is the proper identification of underground utility lines. The American Public Works Association (APWA) has developed a standardized color code system to facilitate this process, used for both above markings and underground warning tape. In this article, we'll delve into what each color means according to the APWA color code:

What Does Red Warning Tape Mean?

Red markings serve as a warning for electric power lines, cables, conduit, and lighting cables. These lines carry electricity to power homes, businesses, and infrastructure. Accidental contact with electric power lines can have severe consequences, making it imperative to exercise extreme caution around red markings; accidentally hitting an electric power line during excavation can result in serious injury or even death, making it crucial to exercise extreme caution when working near red markings.

What Do Orange Markings Indicate?

Orange markings and tape indicate the presence of telecommunication lines, alarm or signal lines, cables, or conduit. These lines carry data, telephone signals, and other communication transmissions. Damaging telecommunication lines can disrupt essential communication services, causing inconvenience and potentially significant financial losses or in some cases safety issues. The use of orange underground marking tape further highlights the importance of these lines, ensuring that excavators proceed with caution to prevent disruption to essential communication services.

What Does a Pipeline Marked with Yellow Signify?

Yellow markings warn of underground gas, oil, steam, petroleum, or other gaseous materials. These lines are crucial for delivering energy resources to various destinations. Accidental damage to these lines can lead to gas leaks, fires, explosions, and environmental contamination. It's essential to identify and exercise caution around yellow markings to prevent hazardous incidents. Yellow tape should be a reminder to excavators of the potential hazards associated with these lines, prompting them to exercise utmost care to prevent accidents and environmental damage.

What's the Meaning Behind Blue Pipeline Markings?

Blue marking and warning tapes indicate the presence of drinking water lines. These lines deliver clean, potable water to homes, businesses, and public facilities. These lines are essential for meeting basic human needs and supporting various activities. Damage to drinking water lines can result in water contamination, service disruptions, and waterborne illnesses. It's crucial to handle excavation activities near blue markings with care to preserve the integrity of these essential utilities and to avoid public health risks.

What is Green Caution Tape for?

Green markings indicate the location of sewers and drain lines. These lines carry wastewater away from buildings and infrastructure to treatment facilities or disposal sites. Damage to green-marked lines can lead to sewage backups, pollution, and health hazards. Proper sewage management is crucial for public health and environmental protection. Proper identification and protection of green-marked utilities are essential to prevent costly and unsanitary consequences. Green underground marking tape serves as a visual cue for excavators, prompting them to take necessary precautions to avoid damaging these critical systems.

What About Purple Marking and Warning Tapes?

Purple markings signify reclaimed water, irrigation, and slurry lines, which transport non-potable water for irrigation and industrial purposes. Damage to these lines can result in water waste and environmental harm. Occasionally purple is also used for “General Purpose” lines that do not fit in the other five color code categories. It's essential to handle excavation activities near purple markings with care to preserve water resources and prevent environmental harm.

Promoting Safety & Preventing Damage

Understanding the APWA color code and utilizing underground marking tape are essential for promoting safety and preventing damage to underground utilities during construction and excavation projects. By familiarizing themselves with the meanings behind each color, workers can mitigate risks, ensure project efficiency, and safeguard critical infrastructure.

If you are interested in learning more about protecting buried infrastructure, check out Signaltape® Underground Warning Tape which not only utilizes the APWA Color Code, but also contains a high strength core that helps to prevent excavation dig-ins.

Copyright © 2024 Damage Prevention Solutions, LLC
3M Authorized ManufacturerMade in USA of US and Imported Parts