diff --git a/speaker_driver.lua b/speaker_driver.lua
index 4f50525..777177d 100644
--- a/speaker_driver.lua
+++ b/speaker_driver.lua
@@ -33,7 +33,7 @@ end
 
 
 
-function playControlRoomAlarm(speakers)
+local function playControlRoomAlarm(speakers)
     for _, speaker in ipairs(speakers) do
         playSound(speaker,"control_alarm")
     end
@@ -72,4 +72,4 @@ end
 local function report()
 end
 
-return { report = report, watch = watch, startup = startup, shutdown = shutdown }
\ No newline at end of file
+return { report = report, watch = watch, startup = startup, shutdown = shutdown, playControlRoomAlarm = playControlRoomAlarm, addSoundFile = addSoundFile }
\ No newline at end of file