Color coding of pipelines and piping materials are standard industry practices. Color marking will make identification easier for raw material and fluid that is being transported by the pipe. There are various national and international Pipe Color Code Standards available. (I have used both British and American versions to spell color/colour)

  1. ASME/ANSI A13.1 – Scheme for the Identification of Piping Systems
  2. BS 1710 – Specification for Identification of Pipelines and Services
  3. IS 2379 – Pipelines Identification Colour Code
  4. PFI ES-22 – Recommended Practice for Color Coding of Piping Materials

Color Coding of Piping Material – PFI ES-22

Why the color coding of piping material?

Various grades of carbon steel, alloy steel, and stainless steel are used during construction and fabrication. To avoid mixing of this material and easy storing and retrieving in the warehouse, piping components such as pipe, fittings, flanges, and valves are color coded.

Most companies have their own color coding system. Pipe Fabrication Institute (PFI) Standard ES-22 provides Piping Materials color coding requirements for the most commonly used piping material grades. It also provides guidance on marking location of piping components.

Refer to below images for the color band location on piping components.

flange marking and color coding
Tee color marking
ss elbow marking
Elbow color code
reducer color coding
ss pipe reducer color code

Color Code for Pipe Material Identification – PFI Standard ES-22 -1999

Carbon Steel Material

Carbon Steel
Material Material Garde Band / Strip Color
Carbon Steel, Electric Resistance Welded   Pipe A53 Gr. B/API 1 solid white
Carbon Steel, Smls, specified tensile   strength under 70,000 psi (483 MPA) A53 Gr. B No Marking
Carbon Steel, killed steel A106 Gr. B 1 solid green
Carbon Steel, specified tensile strength   70,000 psi (483 MPA) and over A106 Gr. C 2 solid green
Carbon Steel, low temperature (impact   tested) A333 Gr. 6 1 solid red

Piping Component Quiz – Test yourself, Take This Quiz

High Yield Carbon Steel

High Yield Carbon Steel
Material Material Garde Band / Strip Color
52,000 min. yield API 5L X-52 1 solid yellow, 1 solid green
60,000 min. yield API 5L X-60 1 solid yellow, 1 solid pink
65,000 min. yield API 5L X-65 2 solid yellow
70,000 min. yield API 5L X-70 1 solid yellow, 1 solid orange

Low Alloy Materials

Low Alloy Materials
Material Material Garde Band / Strip Color
C-Mo steel A335 Gr. P1 1 solid orange
1 Cr-1/2 Mo Steel A335 Gr. P12 1 solid orange, 1 solid blue
1 1 /4 Cr-1/2 Mo Steel A335 Gr. P11 1 solid yellow
2 1/4 Cr-1 Mo Steel A335 Gr. P22 1 solid blue
5 Cr-1/2 Mo Steel A335 Gr. P5 1 solid blue, 1 solid yellow
9 Cr-1/2 Mo Steel A335 Gr. P9 2 solid orange

Ferritic and Martensitic Stainless Steels

Ferritic and Martensitic Stainless Steels
Material Material Garde Band / Strip Color
Type 405 A268 TP405 1 solid green, 1 solid black
Type 410 A268 TP410 1 solid green, 1 solid red

Austenitic Stainless Steels

Austenitic Stainless Steels
Material Material Garde Band / Strip Color
Type 304 A312 TP304 1 solid black
Type 304L A312 TP304L 2 solid black
Type 304H A312 TP304H 1 intermittent black
Type 309 A358 Gr309 1 solid black, 1 solid brown
Type 310 A358Gr310 1 solid green, 1 solid orange
Type 316 A312 TP316 1 solid gray
Type 316L A312 TP316L 2 solid gray
Type 316H A312 TP316H 1 intermittent gray
Type 317 A312 TP317 1 solid brown, 1 solid green
Type317L A312 TP317L 1 solid brown, 1 solid red
Type 321 A312 TP321 1 solid pink
Type 321 H A312 TP321H 2 solid pink
Type 347 A312 TP347 1 solid brown
Type 347H A312 TP347H 2 solid brown

Nickel Based Alloys

Nickel Based Alloys
Material Band / Strip Color
Nickel 200 1 solid black, 1 solid pink
Incoloy 800 1 solid black, 1 solid orange
Incoloy 800H 1 solid gray, 1 solid red
Incoloy 825 1 solid gray, 1 solid blue
Inconel 600 2 solid blue
Inconel 625 1 solid blue, 1 solid pink
Hastelloy Alloy 8-2 1 solid red, 1 solid orange
Hastelloy Alloy C-276 1 solid red, 1 solid blue
Hastelloy Alloy C-22 2 solid red
Hastelloy Alloy G 1 solid red, 1 solid yellow
Carpenter Alloy 20 C 8-3 1 solid black, 1 solid blue
Monel 400 1 solid black, 1 solid yellow

Color Coding of Pipeline and Piping Identification

Oil and Gas Industries, Process industries are complex installations. Piping systems are used in these plants to transport various fluids. These pipelines transport various industrial materials such as gases such as Air, Nitrogen, Oxygen, Hydrogen, etc., liquids such as water, acids, hydrocarbon, toxic materials, etc.

Identifying the material pipeline transporting without a proper pipe color code is extremely difficult. Systematic color coding of pipelines and piping systems is essential to reduce the safety hazard and the possibility of mistakes in identification and accidents associated with the wrong identification of pipelines during an emergency situation. Uniformity of color marking promotes greater safety, lessens the chances of error, and reduces hazards in handling material inside the pipelines.

National and international standards provide the guidelines for uniform color coding in industries that are used to color code of pipes to identify.

  • ASME A13.1 – Scheme for the Identification of Piping Systems
  • BS 1710 – Specification for Identification of Pipelines and Services
  • IS 2379 – Pipelines Identification Colour Code

These standard uses different color code methodology to identify the pipe material. They use a base color, band color, letters, and direction arrow to identify fluid inside the pipeline.

ANSI/ASME A13.1 – Scheme for the Identification of Piping Systems

The purpose of the ASME/ANSI A13.1 Standard is to establish a common system that assists in the identification of hazardous materials conveyed in piping systems and their hazards when released into the environment.

ASME A13.1 – 2015 edition has six fixed colors, and four users define colors that can be used to identify hazardous material. In this standard, the following categories are used;

  1. Flammable – Fluids or vapor or produce vapors that can be ignited and continue to burn in air.
  2. Combustible – Fluids that can burn, but are not flammable.
  3. Oxidizing – Oxidizing fluid is any gas or liquid that may, generally by providing oxygen, cause or contribute to the combustion of other material more than air does.
  4. Toxic and Corrosive – Fluids that are corrosive or toxic, or will produce corrosive or toxic substances when released.
  5. Fire Quenching – Fluid Such as water, foam, and CO2 used in sprinkler systems and firefighting piping systems.

Size of Label and Letters as per ASME B13.1-2015

Outside Diameter of Pipe in Inches Outside Diameter of Pipe in mm Length of Color Field, A, in Inches Length of Color Field, A, in mm Size of Letters, B, in Inches Size of Letters, B, in mm
3⁄4 to 11⁄4 19 to 32 8 200 1⁄2 13
11⁄2 to 2 38 to 51 8 200 3⁄4 19
21⁄2 to 6 64 to 150 12 300 11⁄4 32
8 to 10 200 to 250 24 600 21⁄2 64
Over 10 over 250 32 800 31⁄2 89

BS 1710 – Specification for Identification of Pipelines and Services

BS1710 uses two types of colour coding to identify the content of pipe and hazard.

  1. Base colour – Base colours are used to indicate the content inside the pipe.
  2. Safety colours – These colours are used as band colours that applied in conjunction with the base pipe color code to create various service identifiers.

Other than colour code, additional information regarding the nature of the contents of the pipe by using the following systems either individually or in combination:

  1. Name in full
  2. Abbreviation of name
  3. Chemical symbol and
  4. Appropriate code indications or code colour bands

Size of Label as per BS 1710 -2014

  1. When Only Basic Identification Color Used
Pipe Diameter Minimum Band Width
Up to 50 mm 130 mm
50 mm to 100 mm 275 mm
above 100 mm 450 mm

2. Basic identification colour with code and/or safety colours

Pipe Diameter Minimum Band Width – Basic Colour (1) Minimum Band Width – Safety Colour (2)
Up to 50 mm 50 mm 30 mm
50 mm to 100 mm 100 mm 75 mm
above 100 mm 150 mm 150 mm

IS 2379 – Pipelines Identification Colour Code

IS 2379 is Indian Standard for the colour coding requirements. It is quite comprehensive and a little complex as compared to BS and ASME standards. IS 2379 is more in line with BS 1710. It used the ground colour, band colour, and letter labeling to identify fluid content and associated hazards.

This standard covers piping systems that include pipes of any kind and in addition fittings, valves, and pipe coverings. Supports, brackets, or other accessories are excluded from this standard. This standard is not applicable to pipelines buried underground or used for electrical services.

Refer to the table for the ground colour that used in pipeline marking.

Ground Colours
Substance Colour
Water Sea green
Steam Aluminium to IS 2339
Mineral, vegetable, and animal oils, combustible liquids Light brown
Acids Dark violet
Air Sky blue
Gases Canary yellow
Alkalies Smoke grey
Other liquids/gases which do not need identification Black
Hydrocarbons/organic compounds Dark admirality grey

Size of Label and Letters as per IS 2379 – 1990 (Reaffirmed 2006)

Length of the Colour Band
Nominal Pipe Size (mm) Ground Colour First Colour Band (mm) Second Colour Band
80 NB and below Throughout the entire length or Band no case less than 300 mm 25 4:1 Proportion to the First Colour Band
Letter Size
Outside Diameter of Pipe (mm) Size of Legend (mm)
20 to 30 10
Above 30 to 50 20
Above 50 to 80 30
Above 80 to 150 40
Above 150 to 250 90
Over 250 90

Commonly used Pipe Color Code As per Is 2379

Pipe Colour Code Use in Refinery As per IS 2379
Contents Ground Colour First Colour Band Second Colour Band
Cooling Water Sea green French blue
Boiler feed water Sea green Gulf red
Drinking water Sea green French blue Signal red
Plant air Sky blue Silver grey
Very high pressure steam Aluminium to IS 2339 Signal red
High pressure steam Aluminium to IS 2339 French blue
Medium pressure steam Aluminium to IS 2339 Gulf red
Low pressure steam Aluminium to IS 2339 Canary yellow
Light diesel fuel Light brown Brilliant green
Lubricating oil Light brown Light grey
Flare gases Canary yellow
Nitrogen Canary yellow Black
Oxygen Canary yellow White
Hydrogen Canary yellow Signal red French blue
Naptha Dark Admirality grey Light brown Black
LPG (Liquid) Dark Admirality grey Brilliant green Dark violet

Location of the color band and Labels

Coloring and identification labels on the pipe should apply in such a way that is clearly visible from all the approaches, especially when pipes are overhead. ASME B13.1 and IS 2379 provide guidance on the positions of the labeling. Refer to the table below for the general guideline provided in the standards.

Location of the Colour Band
As Per IS -2379 AS Per BS 1710 & ASME B13.1
At battery limit points Close to valves or flanges
Intersection points and change of direction points in piping ways Adjacent to changes in direction, branches
Other points such as midway of each piping way, near valves, junction joints of service appliances, walls, on either side of pipe culverts where pipes pass through walls or floors
For long stretch yard piping at 50 m interval at intervals on straight pipe runs sufficient for identification
At start and terminating points
Pipe Color Code Position

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Varun Patel - HardHat Engineer

About Author: Varun Patel is a Mechanical Engineer and an Oil & Gas Professional. He is a Certified Project Management Professional – PMP® from PMI® USA. With over nineteen years of experience, he has worked with Fortune 500 Oil & Gas Companies. Know more.