>            It says:   "There has always been a time-honored tradition
> in the construction industry of on-the-spot innovation to solve
> unanticipated problems; the object is to get things done. The
> supercharged regulatory environment squelched this completely,
> seriously hurting the morale of construction crews. For example, in
> the course of many design changes, miscalculations might cause two
> pipes to interfere with one another, or a pipe might interfere with a
> valve. Normally a construction supervisor would move the pipe or valve
> a few inches, but that became a serious rule violation. He now had to
> check with the engineering group at the home office, and they must
> feed the change into their computer programs for analyzing vibrations
> and resistance to earthquakes. It might take many hours for approval,
> and in the meanwhile, pipefitters and welders had to stand around with
> nothing to do."

This can be good or bad as Russell already noted.  On one hand, it's
desirable to "just get it done" and not have to get 13 layers of approval
for a trivial change.  On the other hand, how do you decide whether a chang=
e
is trivial or not without going back to the design engineer who may be awar=
e
of considerations the construction crew isn't.  Maybe it doesn't matter tha=
t
the valve is moved over a few inches, but maybe it does but it's not obviou=
s
to the construction crew.

There are probably thousands of routine cases where the construction crew
made truly trivial adjustments to unworkable plans, and everything has been
fine and a lot of time and money saved.  In fact, that's probably the norm.
However, there are a few cases known where this was done with people gettin=
g
killed as a result.

One such case I remember from the late 1980s(?) was a walkway in a hotel in
Kansas City(?).  The elevated walkway worked fine until one day there was a
celebration going on and large numbers of people were standing on it.  The
problem during construction was that the support design was impossible to
build (bad engineering).  It specified a metal rod that was solidly
supported from something like a roof beam designed to take the load.  The
rod ran vertically down past this walkway to another lower one that it also
supported, and was properly sized to take the combined load.  So far so
good.  The problem was how the upper walkway was tied to the rod.  The
design called for a section of the rod by the walkway to be threaded, with
essentially a nut on the thread which would take the load of the walkway.
The nut and threads were sized appropriately, but apparently there was no
way to get a nut onto the middle of this rod.  It couldn't be built as
designed.

The construction crew instead used two rods.  The top one ended with the
designed nut on thread at a bracket, then another rod went from lower on th=
e
same bracket down to the lower walkway.  This seemed like a simple fix to
the construction crew, but they didn't consider that now the top nut and
bracket were carrying the load of both walkways when these were designed fo=
r
only the load of the top walkway.  In their defense, they did send a memo t=
o
the engineer asking if this fix was acceptable.  They didn't get a answer,
so went ahead with their fix and tens of people died eventually as a result=
..

If I remember right, the engineer was eventually found at fault, not the
construction crew because they had tried to get approval.  However it point=
s
out how construction crews don't have the expertise to know whether their
"fix" is acceptable in the larger scheme of things.  The cost of getting
this wrong in a nuclear power plant can be rather high, so at the least
requiring the appropriate engineer to approve ad hoc changes sounds
sensible.  Of course forcing that engineer to run pointless simulations whe=
n
he knows it doesn't matter is silly, but then you get into who's to judge
whether a simulation is pointless before seeing its result.

Overall things are rarely as clear cut as they might appear at first glance=
..
If you want to give the construction crew some flexibility for the sake of
efficiency, you have to accept a certain number of failures like the Kansas
City walkway collapse.  I'm not saying it is or isn't the right tradeoff,
but that we need to be concious of this tradeoff being made and its
consequences.  If all 300M of us benefit regularly and substantially from a=
d
hoc contruction crew fixes and as a result 50 people get killed every
century due to bad fixes, it's probably the right tradeoff overall.  Of
course the loved ones of those 50 likely won't agree, and will get a
disproportionately larger voice, but that's getting into politics.
Unfortunately one side of the equation is much easier to publisize than the
other.


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