diff --git a/htdocs/core/modules/expensereport/doc/pdf_standard.modules.php b/htdocs/core/modules/expensereport/doc/pdf_standard.modules.php
index 411bc009b8e..d092614dc40 100644
--- a/htdocs/core/modules/expensereport/doc/pdf_standard.modules.php
+++ b/htdocs/core/modules/expensereport/doc/pdf_standard.modules.php
@@ -268,7 +268,7 @@ class pdf_standard extends ModeleExpenseReport
 				$pdf->SetCreator("Dolibarr ".DOL_VERSION);
 				$pdf->SetAuthor($outputlangs->convToOutputCharset($user->getFullName($outputlangs)));
 				$pdf->SetKeyWords($outputlangs->convToOutputCharset($object->ref)." ".$outputlangs->transnoentities("Trips"));
-				if (!empty($conf->global->MAIN_DISABLE_PDF_COMPRESSION)) {
+				if (getDolGlobalString('MAIN_DISABLE_PDF_COMPRESSION')) {
 					$pdf->SetCompression(false);
 				}
 
diff --git a/htdocs/core/modules/facture/doc/pdf_crabe.modules.php b/htdocs/core/modules/facture/doc/pdf_crabe.modules.php
index 39fa07c638a..bf7cb64df77 100644
--- a/htdocs/core/modules/facture/doc/pdf_crabe.modules.php
+++ b/htdocs/core/modules/facture/doc/pdf_crabe.modules.php
@@ -373,7 +373,7 @@ class pdf_crabe extends ModelePDFFactures
 				$pdf->SetCreator("Dolibarr ".DOL_VERSION);
 				$pdf->SetAuthor($mysoc->name.($user->id > 0 ? ' - '.$outputlangs->convToOutputCharset($user->getFullName($outputlangs)) : ''));
 				$pdf->SetKeyWords($outputlangs->convToOutputCharset($object->ref)." ".$outputlangs->transnoentities("PdfInvoiceTitle")." ".$outputlangs->convToOutputCharset($object->thirdparty->name));
-				if (!empty($conf->global->MAIN_DISABLE_PDF_COMPRESSION)) {
+				if (getDolGlobalString('MAIN_DISABLE_PDF_COMPRESSION')) {
 					$pdf->SetCompression(false);
 				}
 
diff --git a/htdocs/core/modules/facture/doc/pdf_sponge.modules.php b/htdocs/core/modules/facture/doc/pdf_sponge.modules.php
index 94b6011b817..1120819e03b 100644
--- a/htdocs/core/modules/facture/doc/pdf_sponge.modules.php
+++ b/htdocs/core/modules/facture/doc/pdf_sponge.modules.php
@@ -400,7 +400,7 @@ class pdf_sponge extends ModelePDFFactures
 				$pdf->SetCreator("Dolibarr ".DOL_VERSION);
 				$pdf->SetAuthor($mysoc->name.($user->id > 0 ? ' - '.$outputlangs->convToOutputCharset($user->getFullName($outputlangs)) : ''));
 				$pdf->SetKeyWords($outputlangs->convToOutputCharset($object->ref)." ".$outputlangs->transnoentities("PdfInvoiceTitle")." ".$outputlangs->convToOutputCharset($object->thirdparty->name));
-				if (!empty($conf->global->MAIN_DISABLE_PDF_COMPRESSION)) {
+				if (getDolGlobalString('MAIN_DISABLE_PDF_COMPRESSION')) {
 					$pdf->SetCompression(false);
 				}