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Re: SI Whining



At 12:53 PM 3/20/98 -0600, you wrote:
>If you are working with stuff every day and are more comfortable with the old
>units, use them.  Use a spreadsheet or a calculator to switch between units
>in which you are comfortable.

It isn't that simple.

Let's look at a complete radiation protection system. We have about 40
people who would be called health physics professionals here, and all of
them could make the switch to SI units easily. But...

The law of the land say "thou shalt use the rem and curie," so what I feel
comfortable is irrelevent. We will use the rem and the curie. Now, if there
is sufficient influence from somewhere, the law can be changed. But it
won't say "use the units you like most." It will impose one set of units
for all to use.

So let's assume we're changed to SI units by federal regulations. What will
we have to do? Well, lots of our more recently acquired instruments already
do SI units, so they're OK. But what about the rest? Regulations are
intolerant - mixing the units on survey forms isn't acceptable, so anyone
using an older instrument will have to modify it to display SI or risk the
continuing mistakes in converting the readings that will happen over the
remaining life of the instrument.

That's the easy part. Retrain everyone on the new units, right? For the 40
HPs, that's no problem. The other 12,000-15,000 people who work or do
research here in a year's time are another subject. All of them are already
primed in the old units and now have to unlearn them, which will have
inevitable problems. Man-years of training, minimum.

How about all those procedures and forms? Remember, the regulation says to
use only the approved units, so every overlooked seldom-used form with mrem
or nCi on it is a violation, as is every mention of mrem not edited out of
procedures. All of this takes a lot of time to deal with. And remember,
there's only 40 of us now, and we've all got enough to do already.

Now let's talk about all those computerized rad protection progams. Your
TLD software must be rewritten to display different units and print them in
the records, and of course, must calculate the numbers differently
everywhere in the software that calculations are done. Can't overlook any
of them. Then move on to the dose tracking software. All of the historical
data are stored in the wrong units. Whether you rewrite the reporting
software to include a method to convert when reporting based on the time of
the data or you convert everything from rem to Sv en mass, it's no trivial
undertaking to get it done right. Then there are the programs that use
electronic access controls that the workers use daily - got to change all
that stuff - minicomputer and mainframe stuff that will cost megabucks to
update. Whole body counter software, too. Sound like the total cost could
be expensive? I think so, too. And when you get done, safety will not have
been improved one bit.

Like I said earlier, I am not surprised at the resistence in this country.
I am amazed at the lack of resistence that happened everywhere else. When
standardizing units used in production of items for international commerce,
the usefulness of the standardized units of measure is obvious. But our HP
program is not in competition with any other program. There are only so
many dollars available, and every dollar spent on a units conversion for
esoteric (political?) reasons and not related to safety of people on the
job is a dollar that won't be spent on safety of people on the job. We
aren't here to serve the wishes of those who are concerned with the finer
technical points about the units of measure; we are here to make the
workplace safe for our co-workers and keep our employer in compliance with
safety regulations.

End of Friday rant. Fade to black. Roll the credits.


---------
Bob Flood
Dosimetry Group Leader
Stanford Linear Accelerator Center
(650) 926-3793
bflood@slac.stanford.edu