diff --git a/src/HAB/Pica/Reader/PicaNormReader.php b/src/HAB/Pica/Reader/PicaNormReader.php
index 14590598815afeefb3d0f3263dc3194e6ddf505e..723748fe28fca79b3b503d383641f1f07acd246b 100644
--- a/src/HAB/Pica/Reader/PicaNormReader.php
+++ b/src/HAB/Pica/Reader/PicaNormReader.php
@@ -230,6 +230,9 @@ class PicaNormReader extends Reader
             if ($buffer === false) {
                 throw new RuntimeException('Error reading input stream');
             }
+            if (strlen($buffer) === 0) {
+                return null;
+            }
             $this->bufferPosition = 0;
             $this->bufferSize = strlen($buffer);
             $this->buffer = $buffer;