diff --git a/webrtc/voice_engine/audio_level.h b/webrtc/voice_engine/audio_level.h
index caecf40689..d69365afb6 100644
--- a/webrtc/voice_engine/audio_level.h
+++ b/webrtc/voice_engine/audio_level.h
@@ -12,6 +12,7 @@
 #define WEBRTC_VOICE_ENGINE_AUDIO_LEVEL_H_
 
 #include "webrtc/rtc_base/criticalsection.h"
+#include "webrtc/rtc_base/thread_annotations.h"
 #include "webrtc/typedefs.h"
 
 namespace webrtc {
@@ -44,13 +45,13 @@ class AudioLevel {
 
   rtc::CriticalSection crit_sect_;
 
-  int16_t abs_max_;
-  int16_t count_;
-  int8_t current_level_;
-  int16_t current_level_full_range_;
+  int16_t abs_max_ GUARDED_BY(crit_sect_);
+  int16_t count_ GUARDED_BY(crit_sect_);
+  int8_t current_level_ GUARDED_BY(crit_sect_);
+  int16_t current_level_full_range_ GUARDED_BY(crit_sect_);
 
-  double total_energy_ = 0.0;
-  double total_duration_ = 0.0;
+  double total_energy_ GUARDED_BY(crit_sect_) = 0.0;
+  double total_duration_ GUARDED_BY(crit_sect_) = 0.0;
 };
 
 }  // namespace voe