Are these standards being relaxed because they were initially set overly cautiously tight, or are they being routinely relaxed without appropriate engineering?
For example, the steam valve leakage. Apparently some leakage is acceptable. Over the years they have quadrupled the allowed leakage and gone from a "per valve" measure to a "total for all valves" measurement scheme. Is the measure there to predict valve failure? Is the measure there to control total radiation release? Cooling water loss? Steaming the staff? I'd have gone "per valve" if I was monitoring the health of the valves and "total aggregate" if I was concerned about the other effect. Did they decide that the "per valve" number was dominated by the other measure?
The article claims the existence of an engineer that thinks the standards are being loosened too much, but if you have three engineers and you can't make one disagree on some things, you have too many engineers.
The motivation for moving from "per valve" to "total for all valves" was cost savings in monitoring. There are thousands of these in plants. Operators didn't want to have to check each one individually, so they got the rule changed to a total measurement.
To actually measure they "randomly" sample their valves, monitor, and then extrapolate to the rest. I say "randomly" because the best ones get checked repeatedly.
The steam valves are designed with pressure relief valves. When pressure exceeds a specified limit, the release is opened to the atmosphere.
Increasing releases is a symptom of other issues in a plant, some very dangerous and some just a reflection on increased utilization.
I have a BS/MS in Electrical & Computer Engineering. For a while I designed/manufactured sensor systems. Our customers were nuclear plants, oil refineries, chemical plants, etc. My company had a line of products that monitored steam valves, among other systems.
For a bunch of reasons I decided to go back to law school and added that skill.
So now I operate at the intersection of law, management/operations, and engineering for small companies. So far it is working out as a good niche.
Are these standards being relaxed because they were initially set overly cautiously tight, or are they being routinely relaxed without appropriate engineering?
I think the problem is that no one really knows. No doubt the original standards were set with substantial safety factors. No doubt time and experience have given us a lot more data on what we can usually get away with.
But the keyword there is "usually". However unlikely a major accident has been, it is getting more likely. And we won't know just how much more likely until it actually happens.
Are these standards being relaxed because they were initially set overly cautiously tight, or are they being routinely relaxed without appropriate engineering?
For example, the steam valve leakage. Apparently some leakage is acceptable. Over the years they have quadrupled the allowed leakage and gone from a "per valve" measure to a "total for all valves" measurement scheme. Is the measure there to predict valve failure? Is the measure there to control total radiation release? Cooling water loss? Steaming the staff? I'd have gone "per valve" if I was monitoring the health of the valves and "total aggregate" if I was concerned about the other effect. Did they decide that the "per valve" number was dominated by the other measure?
The article claims the existence of an engineer that thinks the standards are being loosened too much, but if you have three engineers and you can't make one disagree on some things, you have too many engineers.