diff --git a/tests/UnitTests/TemplateSource/TagTests/Strip/CompileStripTest.php b/tests/UnitTests/TemplateSource/TagTests/Strip/CompileStripTest.php
index 547b3929..f943d08e 100644
--- a/tests/UnitTests/TemplateSource/TagTests/Strip/CompileStripTest.php
+++ b/tests/UnitTests/TemplateSource/TagTests/Strip/CompileStripTest.php
@@ -60,6 +60,9 @@ class CompileStripTest extends PHPUnit_Smarty
 
     /**
      * test strip tag output tag
+     *
+     * @runInSeparateProcess
+     * @preserveGlobalState disabled
      */
     public function testStripOutputTag()
     {
@@ -68,6 +71,9 @@ class CompileStripTest extends PHPUnit_Smarty
 
     /**
      * test strip tag no output tag
+     *
+     * @runInSeparateProcess
+     * @preserveGlobalState disabled
      */
     public function testStripNoOutputTag()
     {
diff --git a/tests/UnitTests/TemplateSource/ValueTests/Modifier/ModifierTest.php b/tests/UnitTests/TemplateSource/ValueTests/Modifier/ModifierTest.php
index 7dca67d4..a719851a 100644
--- a/tests/UnitTests/TemplateSource/ValueTests/Modifier/ModifierTest.php
+++ b/tests/UnitTests/TemplateSource/ValueTests/Modifier/ModifierTest.php
@@ -116,6 +116,8 @@ class ModifierTest extends PHPUnit_Smarty
 
     /**
      * test modifier at plugin result
+     * @runInSeparateProcess
+     * @preserveGlobalState disabled
      */
     public function testModifierAtPluginResult()
     {