An Introduction to ISO 15926 November 2011 - iRINGToday

Why We Need ISO 15926
Traditional ways of exchanging and reusing information all involve some variant of having
someone read one document and then decide which parts to transcribe to a different document.
This is true whether we are moving a single value from one data sheet to another or
mapping entire databases together. Even with modern computer technology, we still rely on
highly skilled people to interpret information and to discern which data values are important.
For this we rely on a surprising amount of context. For instance, when we look at a data sheet
we rely on visual cues and our experience. When we map databases together, we deal with
attribute names that are usually inadequate in themselves to make fine distinctions between
similar terms. To understand what our data means, we need more information than is contained
in the data itself.
This affects us whenever we attempt to exchange information. An obvious large information
exchange is the handover phase of a project. Even though a fully electronic handover is quite
possible today, the documents that are handed over are often still formatted for humans.
Currently, when we hand over information we still have to think about how it is to be accomplished.
This adds friction, making many exchanges uneconomic. When ISO 15926 is mature,
the mechanics of information exchange will fade into the background—allowing more exchanges
to take place economically.
The History of ISO 15926
The reason information exchange, as envisioned by ISO 15926, is possible now is because of
the convergences of four areas of study. The study of how we know things, ontology, gives us
techniques for embedding meaning into data. The Semantic Web gives us the tools to do so.
Open ways of encoding data make it practical to do so. But the most important is the evolution
of product information.
With the advent of CAD software in the late 1970s, we have continually played the role of
Oliver Twist: “Please sir! Can I have more?” At first, all we wanted was to be able to exchange
CAD drawings without having to redraw them and got CAD exchange standards such as the
Initial Graphics Exchange Standard (IGES). Then we wanted the product information that is
behind the drawings in many manufacturing systems and got a standard called STEP, which
we will become very familiar with in the coming chapters. Later, as we tried to apply the principles
of STEP to long-life process plants STEP itself evolved into ISO 15926.
The core of ISO 15926, the data model (called Part 2), and the dictionary (called Part 4) have
been developed in the heat of battle on several large, world-class projects. Dictionary-level information
exchange is now routine. We are poised for an even greater increase in productivity
with the development of techniques for embedding meaning into our information exchanges.
How Does ISO 15926 Work?
“Your computer can talk to my computer and neither of us has to know anything about each
other’s systems beforehand” sounds somewhat magical. Readers are excused for being somewhat
skeptical. But when you consider what actually needs to be exchanged the claim of ISO
15926 becomes more believable. The engineers, fabricators, constructors, and plant operators
INTRODUCTION
8