Uses a list instead of world search

code/_globalvars/lists/objects.dm

@@ -13,6 +13,7 @@ GLOBAL_LIST_INIT(singularities, list())				//list of all singularities
 GLOBAL_LIST_INIT(janitorial_equipment, list())		//list of janitorial equipment
 GLOBAL_LIST_INIT(crafting_recipes, list()) //list of all crafting recipes
 GLOBAL_LIST_INIT(prisoncomputer_list, list())
+GLOBAL_LIST_INIT(celltimers_list, list()) // list of all cell timers
 GLOBAL_LIST_INIT(cell_logs, list())
 GLOBAL_LIST_INIT(navigation_computers, list())
 

code/game/machinery/computer/brigcells.dm

@@ -35,7 +35,7 @@
     var/list/timers = list()
     /*"Detainee [logname] has been incarcerated for [seconds_to_time(timetoset / 10)] for the charges of, '[logcharges]'. \
 	Arresting Officer: [usr.name].[R ? "" : " Detainee record not found, manual record update required."]"*/
-    for(var/obj/machinery/door_timer/T in world)
+    for(var/obj/machinery/door_timer/T in GLOB.celltimers_list)
         var/timer = list()
         timer["cell_id"] = T.name
         timer["occupant"] = T.occupant

code/game/machinery/doors/brigdoors.dm

@@ -36,6 +36,14 @@
 	var/time = 0
 	var/officer = "None"
 
+/obj/machinery/door_timer/New()
+ 	GLOB.celltimers_list += src
+ 	return ..()
+
+/obj/machinery/door_timer/Destroy()
+ 	GLOB.celltimers_list -= src
+ 	return ..()
+
 /obj/machinery/door_timer/proc/print_report()
 	var/logname = input(usr, "Name of the guilty?","[id] log name")
 	var/logcharges = stripped_multiline_input(usr, "What have they been charged with?","[id] log charges")