[Editor's Note: Occasionally, while analyzing systems for criticality safety evaluations, we run into some odd-ball equipment, process, or methodology that we can only trace back to "that's the way it's always been done" or looking at a "crazy" design, we'd exclaim "which horse's ass designed this?" (Younger engineers would exclaim "what the f*ck!" but the intent is the same.) Bearing this in mind, we thought you'd enjoy some perspective on why the Space Shuttle's solid rocket boosters are designed to a certain size. The story starts with the railroad.]

The US Standard railroad gauge (distance between the rails) is 4 feet, 8.5 inches. That's an exceedingly odd number?!

Why was that gauge used? Because that's the way they built them in England.

Why did the English people build them like that? Because the first rail lines were built by the same people who built the pre-railroad tramways, and that's the gauge they used.

Why did "they" use that gauge then? Because the people who built the tramways used the same jigs and tools that they used for building wagons, which used that wheel spacing.

Okay! Why did the wagons use that odd spacing? Well, if they tried to use any other spacing the wagons would break on some of the old, long distance roads, because that's the spacing of the old wheel ruts. So who built these old rutted roads? The first long distance roads in Europe were built by Imperial Rome for the benefit of their legions. The roads have been used ever since then.

And the ruts? The initial ruts, which everyone else had to match for fear of destroying their wagons, were first made by Roman war chariots. Since the chariots were made for or by Imperial Rome they were all alike in the matter of wheel spacing. Thus, we have the answer to the original questions. The United States standard railroad gauge of 4 feet, 8.5 inches derives from the original specification for an Imperial Roman army war chariot. Specs and Bureaucracies live forever. So, the next time you are handed a specification and wonder what horse's ass came up with it, you may be exactly right. Because the Imperial Roman chariots were made to be just wide enough to accommodate the backends of two war horses.

When we see a Space Shuttle sitting on the launch pad, there are two big booster rockets attached to the sides of the main fuel tank. These are the solid rocket boosters, or SRBs. The SRBs are made by Thiokol at a factory in Utah. The engineers who designed the SRBs might have preferred to make them a bit fatter, but the SRBs had to be shipped by train from the factory to the launch site. The railroad line to the factory runs through a tunnel in the mountains. The SRBs had to fit through that tunnel. The tunnel is slightly wider than a railroad track, and the railroad track is about as wide as two horse's behinds. So a major design feature of what is arguably the world's most advanced transportation system was determined by the width of a horse's ass.

Source: amsat-bb@AMSAT.org email from Clifford Buttschardt received on Wednesday, September 22, 1999 5:19 PM

The six former officials of the JCO Tokaimura plant arrested and indicted on October 11th pleaded guilty on charges of professional negligence. JCO pleaded guilty of violating Nuclear Reactor Regulation Law and industrial safety law for failing to provide sufficient safety training to workers. The guilty pleas stemmed from charges associated from the deaths of two of the three workers involved in Japan's first criticality accident on September 30, 1999. This is the first time that arrests and convictions have been made in connection with a nuclear accident. The trial opened Monday, April 23, 2001 with JCO and the six officials pleading guilty to the charges and facing a maximum penalty of one year in prison and a fine of 500,000 yen ($4,098).

Read the Valerie Putman Email.

According to news reports, prosecutors said that JCO knew as early as 1987, on the basis of an in-house inspection, that it was using "illegal equipment and processing measures, such as using steel buckets to dissolve uranium." In 1992, JCO carried out a "secret study" looking into the possibility of a nuclear accident and formed a so-called crisis management committee to discuss the risks of an accident and its worst-case scenario.

Read the Japanesse news article or the CNN article.

NUREG/CR-6686, "Experience with SCALE Criticality Safety Cross-Section Libraries," provides a review of the origins and the data used to create the SCALE libraries as well as a performance comparison supposedly showing general trends and weaknesses. The report establishes acceptability of the libraries for particular fissile systems and applications. The Bazley Institute provides some feedback on discussions of criticality safety cross section selection, rating, and use.

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After experiencing the holidays and having to answer a few more questions from friends and relatives about what we, as nuclear criticality safety engineers, do, the Institute has started work on generating a few web pages to explain to the layman ("—or woman" to quote Life of Brian) what criticality safety is and what a criticality safety engineer does. Along this endeavor, we started looking for some short definitions of who we are and what we do.

Of course, we stumbled upon the classic definitions of some individuals of the criticality safety community. But those definitions were lacking in perspective of what our jobs as engineers were. We could only find one simple definition of what a criticality safety engineer is.

The short definitions are provided below in hopes that a few of you would provide us with some more insight (and hopefully some of your artistic prose) into other or more meaningful definitions of criticality safety and criticality safety engineering. (And would also provide us with any already existing celebrity definitions missed.) We'll add your definition to our list giving you the appropriate credit. Thanks for your help!

Definitions of Criticality Safety

Protection against the consequences of an inadvertent nuclear chain reaction, preferably by prevention of the reaction. — ANSI/ANS-8.1-1998

The art of avoiding a nuclear excursion. — Hugh Paxton

The art and science of not building a nuclear reactor without shielding, coolant, and control — Francis Alcorn

Definitions of a Criticality Safety Engineer

One who, typically by trial and error, realizes that one can not intuitively predict the change in reactivity by any change in any nuclear parameter. — Chris Miller

Email us your definitions!

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head of JCO's Tokaimura plant,

head of the planning group associated with the activities,

chief of the plant's production department,

chief of production for the associated activity,

deputy chief of production for the associated activity, and

senior worker for the associated activity.

The planned criminal charges stem from the deaths of two of the three workers involved in Japan's first criticality accident on September 30, 1999. This is the first time that arrests have been made in connection with a nuclear accident.

Among items cited as the basis for the charges were:

permitting operations to continue although management was aware of illegal work practices,

willingly permitting operations to continue after being asked if procedural deviations were permitted,

failure to follow specific procedures,

failure to notify supervisors of such failure,

improper worker training on criticality safety,

worker procedural knowledge was not assessed or assured by management, and

improper and insufficient supervisory training in criticality safety.

Refer to the following links provided by Valerie Putman.