The code below will suppress the warnings, but your question is so vague that it almost surely won't accomplish the desired end. What is going on? 
$rec->[IMP_WG]    = defined $rec->[IMP_WG]  ? $rec->[IMP_WG]  : '';
$rec->[CSC_HAN]   = defined $rec->[CSC_HAN] ? $rec->[CSC_HAN] : '';
$rec->[CLASSIF]   = defined $rec->[CLASSIF] ? $rec->[CLASSIF] : '';
$rec->[SRV_PLT]   = defined $rec->[SRV_PLT] ? $rec->[SRV_PLT] : '';

print STDERR "$rec->[IMP_WG] $rec->[CSC_HAN]\n";

if ( $rec->[IMP_WG] ne '' && $rec->[CSC_HAN] eq '1' )
{
  print "$rec->[CLASSIF] $rec->[IMP_WG] $rec->[SRV_PLT]\n";
}

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--
Tommy Butler, a.k.a. TOMMY

In reply to Re: split, Use of uninitialized value by Tommy
in thread split, Use of uninitialized value by Anonymous Monk

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