Day 011 - 12 Jul 94 - Page 46


     
     1        presumption that hydrogen is part of the formula, as you
              might call it?
     2        A.  Yes.
 
     3   Q.   I believe that it is true that HCFC-22 was originally
              labelled as CFC-022 and the second of those figures
     4        indicated that a hydrogen atom was present?
              A.  Yes.
     5
         Q.   So there really was not any need to say HCFC-22; a chemist
     6        would understand the chemical structure of that molecule?
              A.  That is true, but I think I would like to point out
     7        that there are two classes of molecules which are actually
              used as transitional substances.  The others are known as
     8        HFCs which contain no chlorine.
 
     9        One reason for introducing HCFC was to make the
              distinction between a hydrogen containing molecule which
    10        is degradable which contains chlorine and a hydrogen
              containing molecule which is degradable which does not
    11        contain chlorine.  So it was not, in fact, purely because
              of the CFCs; it was because, in fact, the entire class of
    12        compounds that were being considered had been widened.
 
    13   Q.   So the decision was made to rename certain parts, certain
              parts of the family, certain of the chemical structure --
    14        sorry, I am losing myself a bit -- that previously have
              come under the CFC family.  Do you think it is true to say
    15        that it was only really when CFCs and HCFCs became an
              issue that scientists and the industry felt there was a
    16        need to add the H so that ordinary people would be able to
              distinguish between the two?
    17        A.  I think I have already given you my reason for why
              I think the H was added, which was that in fact once the
    18        potential of certain CFCs to destroy ozone, particularly
              CFC-11 and CFC-12 became known, then the chemical industry
    19        started looking to a whole range of chemicals which did
              not just include those containing chlorine.  In my view,
    20        it was at -- a personal view -- it was at that time the
              nomenclature was changed.
    21
              I would like to make the point that if you look at the
    22        documentation that all CFCs do not have the same
              destructive potential, and what you have to consider is
    23        the ones which are principally used in the world for
              plastics production and these were CFC-11 and CFC-12.
    24
         Q.   I accept that the general scientific belief is that have a
    25        different destructive potential, but you would accept that
              it was really only when this became an issue that there 
    26        was felt to be a need to relabel CFC-22 as an HCFC?  Prior 
              to that, I mean, the ordinary person in the street would 
    27        not take much notice of this?
              A.  The only reason I was hesitating was that the use of
    28        the word "belief" implies some sort of estimation which is
              very, very sloppy.  I would say it was a matter of
    29        scientific proof that the reactivity of these chemicals
              had a certain -- was of a certain level in that people had
    30        actually studied the reactions of these things and it was
              on the basis of quantitative measurement of these

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