diff --git a/circ/article-request-slip.pl b/circ/article-request-slip.pl
index 2175561edb..7f8aaa4f67 100755
--- a/circ/article-request-slip.pl
+++ b/circ/article-request-slip.pl
@@ -30,7 +30,7 @@ use Koha::Patrons;
 
 my $cgi = CGI->new;
 
-my $id = $cgi->param('id');
+my $id = scalar $cgi->param('id');
 
 my ( $template, $loggedinuser, $cookie ) = get_template_and_user(
     {
diff --git a/tools/batch_delete_records.pl b/tools/batch_delete_records.pl
index c387f98a06..5323341843 100755
--- a/tools/batch_delete_records.pl
+++ b/tools/batch_delete_records.pl
@@ -81,7 +81,7 @@ if ( $op eq 'form' ) {
         }
     } else {
         # The user enters manually the list of id
-        push @record_ids, split( /\s\n/, $input->param('recordnumber_list') );
+        push @record_ids, split( /\s\n/, scalar $input->param('recordnumber_list') );
     }
 
     for my $record_id ( uniq @record_ids ) {
diff --git a/tools/batch_record_modification.pl b/tools/batch_record_modification.pl
index e972bcdf4d..39921dab54 100755
--- a/tools/batch_record_modification.pl
+++ b/tools/batch_record_modification.pl
@@ -112,7 +112,7 @@ if ( $op eq 'form' ) {
         }
     } else {
         # The user enters manually the list of id
-        push @record_ids, split( /\s\n/, $input->param('recordnumber_list') );
+        push @record_ids, split( /\s\n/, scalar $input->param('recordnumber_list') );
     }
 
     for my $record_id ( uniq @record_ids ) {
diff --git a/tools/inventory.pl b/tools/inventory.pl
index 7503e8ce5d..a224306e5b 100755
--- a/tools/inventory.pl
+++ b/tools/inventory.pl
@@ -183,7 +183,7 @@ if ( ($uploadbarcodes && length($uploadbarcodes) > 0) || ($barcodelist && length
             push @uploadedbarcodes, grep { /\S/ } split( /[$split_chars]/, $barcode );
         }
     } else {
-        push @uploadedbarcodes, split(/\s\n/, $input->param('barcodelist') );
+        push @uploadedbarcodes, split(/\s\n/, scalar $input->param('barcodelist') );
         $uploadbarcodes = $barcodelist;
     }
     for my $barcode (@uploadedbarcodes) {