Pipe marking is an important safety practice for any facility that uses pipes to transport dangerous or hazardous materials. Proper pipe markings ensure that the contents of a pipe are immediately and accurately identified, helping personnel to work safely and efficiently. In this article, we provide a quick guide to pipe marking, including best practices and information about the various labeling systems used in the U.S. and other countries. When it comes to pipe marking, the goal is to clearly identify the contents of each pipe, as well as the direction of flow. The most common pipes found in industrial and commercial settings are color–coded. For example, in the U.S., black pipes usually carry non–hazardous materials, while red pipes carry hazardous materials. Different countries have their own systems, but the basic idea is the same. In addition to color–coding, pipes must also be labeled with words or symbols to indicate their contents. The most common labeling system is the ANSI/ASME A13.1 standard, which is recognized in the U.S., Canada, and Mexico. In addition to color–coding and labeling, it is also important to use directional arrows on pipes to indicate the direction of flow. Arrows should be placed on both sides of the pipe and should be of a consistent size and color. This helps personnel to quickly identify the direction of flow and avoid mistakes. Finally, it is also important to use safety signs around pipes to alert personnel to the potential dangers of working with hazardous materials. These signs should be placed in conspicuous locations, such as near valves and other areas of potential exposure. Signs should be clear and easy to read, and should include pertinent information about the contents of the pipe. Overall, pipe marking is an essential safety practice in any facility that uses pipes to transport materials. By utilizing color–coding, labeling, arrows, and safety signs, personnel can quickly and accurately identify the contents of each pipe, helping them to work safely and efficiently.