What should the height of text on a pipe label be?

When using labels in the workplace to convey information it is important to ensure everything is readable from as great a distance as possible. For many things this simply means printing the label with text in a large font so that people can see it from quite some distance away. When labeling pipes, however, that is not always possible.

Given the fact that pipes are sometimes fairly small in diameter, it can be impossible to use large text. To help make the labels as visible as possible, ANSI has set out a standard text height based on pipe size. When followed, labels can be read easily and also contain all the essential text that is needed to be useful. Of course, these labels also use specific color combinations to help convey information quickly and easily.

Established Standards for Text Size

The following are the standards established by ANSI, and often used by OSHA, when it comes to how large the text should be on pipe markings:

  • Pipe Diameter of 0.7" - 1.3’’ – The letters need to have a minimum height of 0.5’’
  • Pipe Diameter of 1.4" - 2.4’’ – The letters need to have a minimum height of 0.7’’
  • Pipe Diameter of 2.5" - 6.7’’ – The letters need to have a minimum height of 1.3’’
  • Pipe Diameter of 6.8" - 10’’ – The letters need to have a minimum height of 2.5’’
  • Pipe Diameter Greater than 10’’ – The letters need to have a minimum height of 3.5’’

These letter heights have been determined to be the ideal balance to ensure they can be seen from a maximum distance, while still fitting on the pipe itself. The size takes into account the fact that the letters can only really be seen from one side of the pipe at a time. Since the labels wrap around the pipe, the lettering needs to be positioned in such a way as to ensure it is visible from where people will be looking at it from.

Not sure which pipe labels you need?  

The pipe label calculator helps you find the supplies you need.

Lengthen the Label to Include Necessary Information

In order to ensure all the vital information is included on a pipe marking, it is often necessary to make the label longer. The extended length of the label will make room to ensure chemical names, warnings, and instructions can all be included in one easy to see place. Of course, you don’t want to make the label too long so that it is difficult to read. Finding the right balance of including important information, but not making it too cluttered, is an important task for all pipe labeling efforts.


View all Pipe Marking Q&A

Free E-Book

Pipe Marking

Streamline your compliance efforts with our pipe labeling guide.


Free Samples

Get samples of our most popular products so you can see the quality before you buy.

Other FREE Resources:

Helpful Resources