Re: Threshold

[William V Lipton <liptonw@DTEENERGY.COM>]

Dream on.



For decades we've been preaching that radiation is a unique and highly

dangerous phenomenon.  This was useful for research support and full

employment.  (As I've stated, a research proposal stating, "Radiation's no big

deal.  Please send money.", is unlikely to be successful.)  Somewhere along

the way, however, we forgot that a successful parasite doesn't kill its host.

Now, even if scientifically valid, it's too late to say, "just kidding."



Whether LNT's valid is irrelevant in any practical sense.  We must learn to

deal with it, or become extinct.



The opinions expressed are strictly mine.

It's not about dose, it's about trust.

Curies forever.



Bill Lipton

liptonw@dteenergy.com



Ruth Sponsler wrote:



> The phrase "_below a certain threshold level_" should

> be added to this statement:

>

> "Why would we reduce unecessary radiation

> exposure _below a certain threshold level_, unless we

> assume LNT?"

>

> Let's assume in a 'future world' on Planet Hardware

> (at the Superstore on Planet Hardware, they sell lots

> of thresholds for doors) that 0.5-14 R/year is

> beneficial, and that 50 R/year is the "NOAEL" [no

> observed adverse effect level].  Biological studies

> have shown that benefits are less at 50R/y than at

> 7-14 R/year, but that there is no harm either.  Harm

> is seen starting at 100R/y.  Planet Hardware has

> instituted a limit of 25 R/year for x and gamma

> because they want to maintain a bit of a 'margin of

> safety.'

>

> One would always reduce unnecessary exposure if it had

> the potential to result in an annual or monthly dose

> above the NOAEL.  So, if someone on Planet Hardware

> had a monthly reading of 2.08R or more, then they

> would have reached their limit for that month, because

> 2.08R x 12mos. = 25.

>

> The practical result of changing from LNT to a

> threshold model is that monitoring would still be

> needed for some things, like industrial radiography,

> nuclear plant operations, radiology, but that levels

> of interest would be more 'liberal.'

>

> Example: Getting zapped with an almost instantaneous

> 70R while trying to inspect welds is a serious

> _oopsie_, and would be regarded as so, even if LNT

> were dropped.

>

> On the other hand, if LNT were dropped, an

> end-of-month reading for a worker repairing pumps or

> whatever of 650 mR (external) would be 'so what,' even

> if 10R/y were the max, because 0.65R(12mos/y) = 7.8

> R/y.

>

> ~Ruth 2

>

> --- Gary Isenhower <garyi@BCM.TMC.EDU> wrote:

> >

> > Thanks for saying that.  I was wondering how many

> > would notice that

> > break in rational thought.  Why would we reduce

> > unecessary radiation

> > exposure, unless we assume LNT?

> >

> > Ted Rockwell wrote:

> > >

> > > > I think

> > > we all agree that if we can reduce unnecessary

> > radiation exposure

> > > at no cost, then we should do so.  This has

> > nothing to do with LNT.

> > > It is just common sense.

> > >

> > > No, that has nothing to do with common sense.

> > It's just LNT.

> > >

> > > Ted Rockwell

>

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