I'm wondering if anybody has ever seen a draft/standard for DCS
... line weight, colours, etc...
Due to ergonomic standards, we're more and more fighting with colour
of keyboards, monitors, etc.. and of course the graphics themselves.
Some of the larger companies (the Shells, BPs, Exxons, Billitons and James
Hardies of this world) have their own "in-house" standards, largely
developed by their long-gone engineering staff from many years ago, but I
must admit that I've never seen anything official from the ISO or anyone
Maybe someone should suggest it to the ISA, but, hey, people can't even
agree whether red is "off" or "on", so a standard for line weights?? I doubt
There are some studies that have been done for GUI's in general and were
some articles back in late 90's in the EE engineering mags, EE Design for
one maybe. I remember reading and was very good.
Google search for "GUI color standards" has some good results and there
does seem to be some ISO or other standards.
GUI or Graphical User Interface is what you want to search and applies to
DCS, SCADA and much more.
I was a member of the ISA SP5.5 committee in the early 80's that
developed a standard for graphic symbols (pumps, heat exchangers,
etc.) used on operator displays. That standard covered symbols only.
The standard was used by the major DCS vendors to develop the prebuilt
symbols for their graphics package.
Since that time there has been occassional discussion about needs for
additional standards. However, as far as I know no committee has been
I do not know that there is a need for national or international
standards in this area. There is a need for internal plant standards;
they can be written by individual companies. There is also a need for
education, written material (books, articles, etc.) making
recommendations and providing guidlines. (I wrote a few articles in
the 80's on the subject)
Process Control Solutions
It's just as well there are no significant standards yet., We are STILL in
the learning curve. What looked cool ten years ago is now recognized as
gaudy and distracting. Black backgrounds were terrible for reflecting
light. Old standards for line weights are totally irrelevant in an age of
fully scalable Windows.
The Honeywell ASM group has material on good graphics design principles but
to be a member is expensive. They have no directly applicable standards.
We are developing our own.
As I think and from my work experience in DCS projects, the HIM is a
customer specification and each project has its own pallet (as we call
it with Foxboro IA). Unfortunately, there are no common standard for
the DCS HMI even for the symbols, there are still some differences
alive within the same symbol used in different projects.
As I think, the lack of standardization is due to the lack of the DCS
standardization as a communication and control system. The DCS still
considered as a vendor dependent technology. There is no a common
standard collect the design and the features of the DCS, although each
system includes a lot of standardized technologies in its core design.
For these reason, the best is to set with the customer and get what
they want exactly and save it as a design kit for that customer for
any further work.
Taking a step back for a sec, it's amazing what can be done using a "text
only" style display (ie. no graphics at all!) ..and the bigger the text,
I know several materials-handling process industries (like steel mills and
plating shops), where pages of text showing the status of each plant item
are more useful to the operator than any flashy graphics. Two reasons come
1. It is far easier to read percentages (as a number, not from a slider)
and status ("off" is longer than "on") as text rather than colour.
2. If the operator is colour-impaired and either doesn't know himself or is
too proud to tell anyone, you'll get an incident before you find out..
Have to agree with all of you...
We also have our own standard, but this one was established in the
80's for a Beckmann RMV9000 and never updated since :-))
Text-only (groups) is what the operators use a lot.
Also the cool ten years old graphics is what we "copied" when we
migrated to a new win-based system.. :-)
Simply because operators were used to those and they didn't want to
have them changed!
What I want to point out (and this is why I asked for a standard) is
are more and more ergonomic standards popping up, dealing with
And this is what DCS systems are nowadays! These standards force us to
change the graphics via ergonomic reasons.
One ergonomic standards forces us to have a min distance of 90cm for
...this again forces us to create graphics with larger symbols/text...
...next step is to split up graphics into several as the original
won't fit anymore...
Another standard calls for the ability to let the operator chose
between positive and negative display (Background black or white/grey)
...how does one handle this...?
I could go on now. Standardizing graphic symbols was already one step,
but there should be more, at least recommendations, describing things
-colors for materials
-bad quality color
With *text* displays - two identical pages with different background
You will find (after a few minutes of research) that the only way to comply
with the ergonomic standards you mention is to use text-only (no graphics at
all) - although don't bother explaining that to your average HMI saleman!
Blame the millions of secretaries, store checkout people, telemarketers and
travel agents around the world - you will never see any of *them* using
Yes, well.... We configure graphic displays all the time, but everyone
(especially plant operators) has their own opinion as to what they want to