If a facility only has the need for using the ANSI/ASME A13.1 standard, then normal gaseous materials should follow that standard. However, gas mixtures or those that are being used for medical purposes must follow the NFPA 99/CGA C-9 pipe marking standards. It may seem surprising but there are quite a few other pipe marking standards that certain facilities must follow.Within the NFPA 99/CGA C-9 standard, the three elements that must be included on a pipe marker are:The contents of the pipeThe direction of the flowThe level of pressureMany of the gaseous substances in these environments are flammable which is why the NFPA is the entity that has created these standards for OSHA to enforce. The following are the color code combinations that must be used:White lettering on a green background is for oxygen USPWhite lettering on a gray background is for carbon dioxideWhite lettering on a blue background is for nitrous oxideBlack lettering on an orange background is for cyclopropaneWhite lettering on a brown background is for helium USPWhite lettering on a black background is for nitrogen NFBlack lettering on a yellow background is for medical air USPWhite lettering on a red background is for instrument airWhite lettering on a purple background is for waste anesthetic disposalBack lettering on a white and yellow checkerboard pattern is for laboratory airBlack lettering on a black and white checkerboard pattern is for laboratory vacuumBlack lettering on a white background is for medical-surgical vacuumThere are also regulations regarding gaseous mixtures that must be followed to ensure worker safety. Those standard color combinations can be found here.Overall, it is good to remember that the ANSI/ASME A 13.1 standard is not the only pipe marking standard out there. There is one pertaining to sea vessels and ones for water treatment facilities, and even extras for commercial buildings. Similar Questions Is there a color code for pipelines?What are pipe labeling standards for sea vessels and marine environments?What are ANSI’s Pipe Labeling Standards?What are the ANSI standards for pipe color codes?What do user-defined color combos mean for pipe marking?what does a yellow pipe label mean?What are the different standards of pipe marking?Can I create custom pipe labels and still be compliant?What is the difference between pipe markers and the NFPA diamond?Additional Resources A Guide to Pipe Marking StandardsPipe Color Codes – ANSI/ASME A13.1ANSI Color Codes for Pipe MarkingSafety Colors (OSHA Guidelines and Color Codes)Your Guide to Pipe Labeling Standards

What color code is used for a piping system conveying gaseous elements?

Pipe Marking

If a facility only has the need for using the ANSI/ASME A13.1 standard, then normal gaseous materials should follow that standard. However, gas mixtures or those that are being used for medical purposes must follow the NFPA 99/CGA C-9 pipe marking standards. It may seem surprising but there are quite a few other pipe marking standards that certain facilities must follow.

Within the NFPA 99/CGA C-9 standard, the three elements that must be included on a pipe marker are:

The contents of the pipe
The direction of the flow
The level of pressure

Many of the gaseous substances in these environments are flammable which is why the NFPA is the entity that has created these standards for OSHA to enforce. The following are the color code combinations that must be used:

White lettering on a green background is for oxygen USP
White lettering on a gray background is for carbon dioxide
White lettering on a blue background is for nitrous oxide
Black lettering on an orange background is for cyclopropane
White lettering on a brown background is for helium USP
White lettering on a black background is for nitrogen NF
Black lettering on a yellow background is for medical air USP
White lettering on a red background is for instrument air
White lettering on a purple background is for waste anesthetic disposal
Back lettering on a white and yellow checkerboard pattern is for laboratory air
Black lettering on a black and white checkerboard pattern is for laboratory vacuum
Black lettering on a white background is for medical-surgical vacuum

There are also regulations regarding gaseous mixtures that must be followed to ensure worker safety. Those standard color combinations can be found here.

Overall, it is good to remember that the ANSI/ASME A 13.1 standard is not the only pipe marking standard out there. There is one pertaining to sea vessels and ones for water treatment facilities, and even extras for commercial buildings.