Re: Luck and analysis

[Doug Aitken <daitken@sugar-land.oilfield.slb.com>]

At 10:53 AM 3/9/2004 -0700, Brian Rees wrote:

>Now hold on here a minute.  Some people are referring to a heat transfer 

>factor that was not analyzed at TMI, one that was greater than expected, 

>causing a conservative result.  That's what conservative calculations buy 

>you.  When we do calculations (at least when I do them) in health physics, 

>a factor may not be fully analyzed, we know from our professional 

>experience and training that its effect will be more conservative than the 

>assumption we make, so we move on.  We don't analyze every stinkin' factor 

>to the nth degree, it's not warranted.   So when something bad happens 

>it's not as bad as we "predicted", although we're already ignoring the 

>conservatism we used.

>

>Now I don't want to say that TMI was without some luck, there were still 

>things that should not have happened, but it was not just luck that kept 

>things from getting dangerously ugly.



I'm sorry if I sound a bit of a cynical ass, bit I'm not sure that there is 

a rigorous logic to the argument above...



1) heat transfer not analyzed ( = no calculations?)

2) fortuitous result (no rupture) = conservative result

3) that's what conservative calculations buy you....



Followed by some back-up in the form of "we don't need to know or calculate 

everything, as long as we, with our professional experience, always shoot 

conservatively.

And if things go wrong, they won't be as bad as we expect.



At least, that seems to be what was said.



Which brings up a couple of important issues.

First (and this goes to the whole thread) partial information can lead to 

false extrapolations, leading to erroneous conclusions (and I have been on 

the end of one of these discussions with Norm Cohen in the past, over a 

radiation exposure from a dropped logging source).



So we should be careful to try and clarify all the facts when publicly 

disclosing information. Otherwise, incomplete information can lead to 

erroneous conclusions. Often, such a disclosure, especially in the 

immediate aftermath of an accident is (a) impossible - due to an ongoing 

investigation and (b) legally unwise. But any report on an incident should 

try to be a clear and objective as possible. And we should not be afraid to 

say "we don't yet have an answer, but will report when we do"



Second: Hiding behind a cloak of scientific jargon (or professional 

credentials!) inevitably leads to a negative outcome. This is especially 

important when dealing with technical stuff in front of the media (and the 

public). If we use too much jargon, we lose the message. Simple, honest 

statements go a long way to gaining credibility. And it is way better 

(after a full investigation has uncovered the root cause of any incident) 

to admit errors where they occurred, along with the remedial or preventive 

steps put in place to minimize the potential for recurrence.



(but unfortunately, few in the media have the patience to really understand 

scientific discussions, preferring quick sound-bites. Which is why the 

anti-nukes have an easier time than the proponents who try rational 

argument....) - a true dilemma.



If we go back to the original thread, Jim Dukelow stated "It was actually 

not luck, but a previously unanalyzed aspect of heat transfer during the 

accident."

My contention was (and is, based on this one sentence) that if it was 

unanalyzed, we cannot say that we were prepared and that luck played a 

(large?) part in the outcome. However (and going back to my first point 

above) I may have drawn an unfair conclusion, based on incomplete 

information. But unfortunately, if I was an anti-nuke, I could get great 

mileage out of quoting this sentence (obviously out of context!).



PS: This is not in any way a personal attack on any of the people involved 

in this discussion. I am just trying to point out the pitfalls of 

communications in the aftermath of an incident. If I offend anyone, I 

apologize in advance. And of course, my comments are mine alone and in no 

way reflect the opinion on any companies with which I may be associated!











Doug Aitken		Schlumberger Drilling and Measurements QHSE 

Advisor

Phone (Sugarland):   	281 285-8009

Phone (Home office): 	713 797-0919	

Phone (Cell): 		713 562-8585

Principal E-mail: jdaitken@earthlink.net

Schlumberger E-mail: daitken@sugar-land.oilfield.slb.com

Mail: 	300 Schlumberger Drive MD2, Room 111

	Sugar Land, TX 77478









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