Automation standards: who publishes what, and how to find the set that applies to your machine

Three layers of publisher, one body of technical content

International bodies publish documents intended for worldwide use. Regional bodies, notably the European standardisation organisations, adopt or develop documents for a regional market and withdraw conflicting national ones. National bodies then issue the regional or international text under a national designation and, in some fields, maintain their own. The same technical content therefore appears under several designations, and a specification citing one may not be citing the same edition as another. In the United States the coordinating body accredits a range of standards developers rather than writing most documents itself, so the name on the cover is frequently a technical association.

The division between the two main international bodies

Two international organisations dominate. One publishes across general engineering, materials, management systems and mechanical topics; the other covers electrical, electronic and related technologies, which takes in industrial control, instrumentation and much of the safety-related control field. Automation straddles that boundary, so joint committees and parallel documents are common, and a machine is typically assessed against both mechanical and control-related documents from different publishers. When somebody states that a machine complies with a standard, the useful follow-up questions are which publisher, which designation, which edition, and which parts fell within the scope of the claim.

How a voluntary document becomes the one you are judged against

Standards are voluntary in themselves. Three mechanisms make one binding. Legislation may reference a document directly or, in some jurisdictions, treat conformity with a listed document as evidence of meeting a legal duty, which the compliance function should confirm market by market. A customer contract may require it, in which case it binds regardless of law. And your own specification may cite it, at which point a supplier is entitled to hold you to precisely what you cited and nothing more. Cite deliberately, name the edition, and make sure somebody has read the document being invoked.

Finding the applicable set for a specific machine

Machinery documents are arranged in a hierarchy running from general principles, through documents addressing one safety aspect that applies across many machine types, down to documents covering a specific type of machine. The practical route is to start at the machine-specific level where such a document exists, since it points to the aspect-level material relevant to that machine, and to work upward only when nothing specific is published. Suppliers should state which documents they designed against, and that statement belongs in the purchase specification rather than appearing on a declaration after delivery.

Licensing, revisions and keeping a library that is current

Standards are copyrighted publications sold document by document, so a plant that cites them needs a controlled library and somebody responsible for it. Documents get revised, sometimes with technical change, and an undated citation in a specification means whichever edition is current at an unspecified moment, which is a weak basis for a contract. Decide whether your specifications use dated or undated references and apply that consistently. Budget for the library, restrict copying to what the licence permits, and review citations when a document is revised, because a specification quoting a withdrawn edition creates an argument at the worst time.

Frequently asked questions

Are standards legally binding?

Not on their own. A standard becomes binding when legislation references it, when a contract requires it, or when your own specification cites it. In several jurisdictions a published list of standards carries a status making conformity useful evidence that a legal obligation has been met, which is why suppliers cite those documents so readily. Whether a particular standard carries legal force in a particular market is a compliance question to answer for that market rather than a property of the document.

Which body's standards apply if we sell into several regions?

Usually more than one, and they are often the same technical text under different designations. The workable approach is to establish the requirements for each destination market first, then identify where one design satisfies all of them and where genuine divergence forces a variant. Regional differences in electrical supply, marking and documentation cause more trouble in practice than the underlying safety requirements. Settling this at design stage costs far less than discovering at shipment that a market expects something else.

Can we cite a standard in a purchase specification without holding a copy?

You can, and it is a poor idea. Citing a document nobody has read means you cannot judge a supplier's conformity claim, cannot tell which parts are relevant, and cannot argue scope when a dispute arises. Buy the documents your specifications depend on, hold them in a controlled library with the edition recorded, and make sure the engineer writing the specification has read the sections being invoked before the order goes out.