Hitting one trigger activates all triggers?

Hi everyone,

I'm making a maze game, and I have a button object that, when the player stands on it, sends another object a message to activate. For example, if the button is connected to a door, standing on the button sends a message to the door to open.

My code works, but it appears to trigger the code on every button I have in the scene, rather than just the one which was touched. Can anyone tell me what I'm doing wrong?

 #pragma strict
 
 // DEFINE VARIABLES
 static var beingUsed : boolean = false;            // Is the device is currently being used?
 var connectedTo : GameObject;                    // When the progress bar hits 100%, what object is activated/deactivated?
 }
 
 function OnTriggerEnter(obj : Collider) {
     
     if (obj.name == "Player_Spy" || obj.name == "Player_Hacker")
         beingUsed = true;
         
 }
 
 function OnTriggerExit() {
 
     beingUsed = false;
 
 }
 
 
 function Update () {
 
     if (beingUsed)
         connectedTo.SendMessage("Activate", SendMessageOptions.DontRequireReceiver);
     else
         connectedTo.SendMessage("Deactivate", SendMessageOptions.DontRequireReceiver);
 
 }