What is the Difference between Code, Standard and Specification?

The difference between Code, Standard and Specification is very important.

What is Standard?

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Below maybe easy understand:

Standard can define as a set of technical definitions and guidelines – or simply a “how to” instructions for designers and manufacturers. It gives all the necessary requirements for the product, service, and operation.

A designer will use the standard to design the product, and a manufacturer will use the standard for the manufacturing of the product.

Standard serves as a common language for defining quality and establishing safety criteria for the product. ASTM, API, ISO are some examples of the standard. ASTM has more than 12000 standards they cover all most everything.

What is Code?

When governmental bodies adopt the standard and become legally enforceable, or when it has been incorporated into a business contract, the standard will become a code.

ASME Codes are legally enforceable in many US state. Whereas, in the other part of the world they are not legally enforceable but such countries have their own similar codes.

Please note that requirements mentioned in the code will only be mandatory requirements if

The Code is adopted as law by a regulatory body
It is a part of the business contract

Otherwise, Code will serve as generally accepted guidelines for design, fabrication, construction, and installation,

However, all most all process facility follows various American code and Standard in addition to their national standard.

Examples of the codes are ASME Boiler and Pressure Vessel Code, BS, DIN, etc.

What is Specification?

Specifications provide specific/additional requirements for the materials, components or services that are beyond the code or standard requirements

For Example, if you want A106 Gr B pipe with Maximum carbon of 0.23% against standard requirements of 0.3% Max, you have to specify your requirement in your specification or Purchase Order.
Specification is generated by private companies to address additional requirements applicable to a specific product or application.

Difference Between Code, Standard and Specification in Piping.


Enforceable by Law or by contract	Globally accepted “how to instruction”	Must meet requirements by Contracts
Written by government or government approved body	Written by public organization or by government body	Written by private companies
Guidelines for design, fabrication, construction and installation	Set of technical definitions and guidelines for manufacturing	Additional requirements, beyond code & standard
ASME, BS, IS, DIN	ASTM, SAE, ISO	Shell DEP, EIL Spec.