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Oil  Spill  identification  -  Round  Robin  20045

1.  Introduction

Note
For  literal  quotations  of  parts  of  reports,
publications  and  letters,  In  this  report
the  typesetting  of  the  text  to  the  right  Is
used

1.1  Invitation
The  round  robin  started  with  this  invitation  by  email  with  enclosed
letter  on  19-5-2005:

Dear  all,
RIZA  (Institute  for  inland  water  management  and  waste  water  treatment)  is  a
governmental  institute  responsible  for  the  environmental  quality  of  the
surface  water  in  the  Netherlands.
One  of  our  tasks  is  the  comparison  of  oil  samples  from  spills  with  possible
sources.
For  many  years  we  have  exchanged  spill  samples  each  year  with  the  Dutch
Forensic  Institute  (NFI)  for  quality  assurance.  The  results  of  each  exchange
were  evaluated  in  a  report  with  the  original  reports  as  appendix.
Due  to  questions  of  other  laboratories  we  started  together  with  BSF1
(Bundesambt  fur  Seeschifffahrt  und  Flydrographie)  last  year  to  organize  an
(inter)national  round  robin.  The  round  robin  of  2004  (RR2004)  was  dealing
with  gas  oil  (diesel)  samples.  Fifteen  laboratories  of  nine  countries
participated,  resulting  in  a  general  report  and  15  original  reports  as
appendixes.  The  results  are  available  on  request.
Samples  and  analysis  method
It  is  intended  to  use  each  year  a  different  kind  of  sample.  This  year  our  study
deals  with  three  to  four  bilge  samples  (diesel-lubricating  oil),  which  must  be
compared.
In  most  Round  Robins  a  method  is  prescribed.  Oil  Spill  Identification
however  is  a  typical  “expert”  method.  Analytical  methods  can  be  given,  but  at
the  end  an  expert  has  to  take  the  decision  based  on  all  information.  For  us  the
RR  is  a  means  to  inform  each  other  how  to  deal  with  cases.
From  the  results  of  RR  2004,  it  can  be  seen  that  most  of  the  laboratories  have
an  own  method,  although  a  lot  of  them  follow  more  or  less  the  Nordtest
method.
The  CEN  working  group  CEN/BT/TF  120  intents  to  finish  in  June  an
European  guideline  for  sampling  and  oil  spill  identification  of  waterborne  oil,
based  on  the  Nordtest  method.
So  for  next  year  we  can  advice  to  follow  this  guideline  and  discuss  and
compare  the  results  of  the  laboratories  that  have  followed  it,  in  more  detail.
But  in  general  each  laboratory  has  to  follow  its  own  standard  procedure  for
oil  comparison.
The  resulting  report  should  not  only  consist  of  a  simple  yes  or  no,  but  also  a
summary  of  the  procedure  should  be  given,  together  with  detailed  results  and
reasons  why  a  decision  has  been  taken.