Re: Gy and Sv = J/kg

[JMUCKERHEIDE@delphi.com]

I don't know who wrote this, but it is right on!   (except for the part about
sending this to Charlie Meinhold, since that is no way to get the science
considered)  including the last paragraph that reflects also that not only is
Q or Wr not dimensionless, but can have no unique value and so is a
meaningless scientific term. Ref NCRP 104 which demonstrates that such a term
can not be defined. (The fact that Meinhold and Sinclair can simply ignore
this and can push and promulgate later reports that simply ignore this report
confirms the lack of any science in their policy operations; again, even
though there is a lot of good science in specific work below the gov't-funded
rad protection policy level.) Join with Victor Bond and others in applying
imparted energy, with an analysis that is sensitive to and demonstrates the
scientific significance of applying units and dimensions to the analysis,
consistent with sound science, and contrary to "rad science". 

How do you get it considered? Send it to Members of the identified
organizations, and to the literature. Better yet, start a professional society 
of knowledgeable scientists to work on the science of the problem.  (An
"International Committee on Radiation and Health" ?  with a mission to address 
the science and also to stop constraining rad science to the one-sided control 
of the _Radiation Protection_   - at any cost! -  non-scientific interests.) 

> Date: Sat, 05 Oct 1996 20:49:06 -0500
> From: integray@ix.netcom.com
> Subject: Re: Gy and Sv = J/kg
> Sender: radsafe@romulus.ehs.uiuc.edu
> 
> I gave this to Charlie Meinhold in 1990 after reading the draft of ICRP 
> Publication 60 (remember "effectance?"):
> 
> A DIMENSIONLESS Q OR wR VIOLATES CONSERVATION OF ENERGY
> 
>         The ICRU, ICRP, CGPM, and NIST must abandon the nonsense that Q and wR 
> are dimensionless.  
> 
>       The claim by the ICRP and the ICRU that both the gray and the sievert have 
 > dimensions of J/kg results in 20 J/kg = 1 J/kg when alpha particles are in
quest > ion, 

> since 1 Gy = 20 Sv.  Merely claiming loudly and repeatedly that Q is a dimension
> less 
> weighting factor does not avoid the logical trap of creating energy from nothing
> ness 
> by using a committee-generated multiplying factor.
> 
>         Consider the analogous example of liters (L) of fuel and kilometers (km)
>  of 
> distance traveled by an automobile.  Suppose we have a standard, reference autom
> obile 
> that travels 10 km/L, and a new, improved model that travels 20 km/L of fuel bur
> ned.  
> When we perform an experiment by putting 10 L of fuel in each car, the cars trav
> el 
> 100 and 200 km, respectively.  The Relative Fuel Effectiveness, RFE, for the two
>  cars 
> is 200/100 = 2.  Clearly, the new, improved car behaves as if it were the standa
> rd 
> reference car with 20 L of fuel.  But in no sense did we have 20 L of fuel in th
> e new, improved car!
> 
>         Similarly, a biological system irradiated with 0.1 Gy of alpha radiation
>  may 
> behave as if it had been irradiated with 2 Gy of beta radiation, but we never ha
> d 2 
> J/kg in the alpha experiment; we only had 0.1 J/kg.  We take this difference in 
> biological behavior into account through the use of dose equivalent (should it b
> e 
> called dose behavior?), calling the 0.1 Gy of alpha-radiation 2 Sv.  In no physi
> cal 
> sense is 2 Sv of alpha-radiation 2 J/kg.
> 
>         The ICRP and the ICRU can extricate themselves from the problem by recog
> nizing 
> dose equivalent for what it is:  a quantity that bears a special relationship to 
 
> energy per unit mass through dimensioned weighting factors, Q (or wR), in Sv/Gy.
> 
>         How did the ICRP and the ICRU fall into this logical trap?  Quite simply
> , Q was 
> originally taken as an average RBE for various kinds of radiations.  RBE is a ra
> tio 
> of two doses, and therefore dimensionless.  Q, however, is not a ratio, and can 
> have 
> dimensions; in fact, it must have the dimensions of Sv/Gy in order for the 
> definitions of dose equivalent and effectance not to violate the well-establishe
> d principle of conservation of energy.
> 
>         All other weighting factors are dimensionless, but Q and wR must have di
> mensions of Sv/Gy.
> 
>         Note that the inclusion of a so-called dimensionless Q in the specific e
> ffective 
> energy (SEE) values in the ICRP Publications 30 and 61 methods makes the results
>  of 
> those calculations for mixed alpha-beta emitters useless when the Qs or wRs chan
> ge.  
> Keeping the internal dose components separated by radiation type would be a much
>  more 
> useful service to the user of the ICRP Publications.  Leave Q out of the energy 
> terms 
> weighted by absorption fractions (call them, perhaps, absorbed energies) and tab
> ulate them separately by radiation type.

Thanks 'integray'.  :-)

Regards, Jim Muckerheide
jmuckerheide@delphi.com