Just one more solution using the input record separator special variable ,$/. It does make a few assumption about the structure of the data though.

use strict;
use warnings;

my $header = <DATA>;
$/ = "\n\n";

while (<DATA>) {
    if (/ 1\n.* 3\n/s) {
        my $id = substr($_,0,11);
        print "good for $id\n";
    }
}

__DATA__
field1 field2
3-2000/7.48 1
3-2000/7.48 2
3-2000/7.48 2
3-2000/7.48 2
3-2000/7.48 2
3-2000/7.48 2
3-2000/7.48 2
3-2000/7.48 3

4-0000/8.40 2
4-0000/8.40 2
4-0000/8.40 2
4-0000/8.40 2
4-0000/8.40 2
4-0000/8.40 2
4-0000/8.40 3

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In reply to Re: validating file with perl by si_lence
in thread validating file with perl by mmittiga17

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