A longer-than-usual weekly posting… maybe a reward for posting two days later than usual???
J
We take so many things for granted – how we walk, what we eat, where we go – that we hardly think about the mechanics or reasons behind all these things.
Take the work processes in a manufacturing plant.
Most plants have definite procedures for the common activities – flanging a line, replacing a valve, etc., etc. Our most common work processes are well-known across the industry. And most are well-documented as industry standards in order to maintain a certain level of safety and reliability.
Everything is so very well ordered, isn’t it? Or is it?
Compare a line lock-out work procedure with one for modifying the control system.
The line lock-out procedure requires multiple sign-offs, tagging of lines, visual pre- and post-inspections, more sign-offs, etc etc.
Changing the name of a control loop or the limit of an alarm setting rarely comes with such complicated work processes. But the unintended consequence of these changes can be as great as any valve replacement. Just think of the BP Texas City incident, where, as Ian Nimmo of UCDS puts it – one level, one alarm and an operator led to catastrophe and significant loss of life (watch animation)
So why are we so comfortable just going with the work processes the way they are?
Maybe because, individually, we can’t change them, even if we tried. Or maybe its because we’re just “stuck” in that’s how things are.
Taking them for granted, as it were.
Let’s think laterally with a vertical example (pun intended)
Consider the elevators used in a high rise buildings.
The elevator has been around since the turn of the century, and very little has changed since then. Well… the elevator operator has been replaced with CNN, the metal cage doors are replaced with stainless steel, but generally speaking, little has changed.
The opportunity singled out as the “next big thing” in the world of vertical ascent is the application of digital technology. More specifically, advanced control and planning applications. Read more from a recent NPR broadcast.
The basic idea is that a bank of elevators should smarten up so as to know where to stop and how to schedule their movements to minimize overall wait time subject to constraints. This is the same thing the oil industry does for crude processing, the airline industry does for flight planning, and on and on..
So what’s the point?
If a little enhancement to the work process of something so well-established as a bank of elevators can bring significant benefit, so can re-visiting the work processes for the “soft” changes to a process plant.
So…why don’t we have a common sign-off process for control system changes anyway?
And how many more Texas City events does it take to bring this about?
Or maybe it’s too complicated and an easier solution is to apply the use configuration management software (like they do in healthcare and many other industries).
Doing this would allow those of us in the process industries to also track and manage every single change made to our systems.
Just think of the improvements to inter-departmental collaboration by automatically notifying those across multiple departments that need to know. And the obvious safety & reliability benefits….
After all, doesn’t the operator deserve to know that the alarm limit on his level transmitter has been changed – or disabled?
Integrity. Don’t operate your plant without it.
Change. Better to manage it than have it manage you.
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