Alarm boxes are objects in Return to Castle Wolfenstein used to sound the alarms and alert stations to enemy presence. The big red button can switch alarms off or on by the player. One way to prevent an alarm box from being sounded is its destruction: shoot, kick, or otherwise attack it until it breaks and bursts into sparks. Enemies will be alerted if they notice the destroyed alarm box. Prevent any alarm from being sounded, especially in "no alert" levels. Sometimes the enemy backup will arrive once the alarm is sounded, this attribute is reused in Wolfenstein: The New Order, although only the officer can trigger the alarm and call backup.
An Alarm box can be found in one of the first rooms of the game (in Escape!), near some conversing Germans: it is broken however, even before the player arrives. The next is a fully functioning one.