diff --git a/code/datums/cache/air_alarm.dm b/code/datums/cache/air_alarm.dm
index 366c68afc0a..07caea0f3ad 100644
--- a/code/datums/cache/air_alarm.dm
+++ b/code/datums/cache/air_alarm.dm
@@ -1,6 +1,6 @@
 var/global/datum/repository/air_alarm/air_alarm_repository = new()
 
-/datum/repository/air_alarm/proc/air_alarm_data(var/list/monitored_alarms)
+/datum/repository/air_alarm/proc/air_alarm_data(var/list/monitored_alarms, var/refresh = 0, var/obj/machinery/alarm/passed_alarm)
 	var/alarms[0]
 	
 	var/datum/cache_entry/cache_entry = cache_data
@@ -8,15 +8,20 @@ var/global/datum/repository/air_alarm/air_alarm_repository = new()
 		cache_entry = new/datum/cache_entry
 		cache_data = cache_entry
 
-	if(world.time < cache_entry.timestamp)
+	if(!refresh)
 		return cache_entry.data
 
-	for(var/obj/machinery/alarm/alarm in sortAtom((monitored_alarms.len ? monitored_alarms : machines)))
-		if(!monitored_alarms.len && alarm.z != ZLEVEL_STATION && alarm.z != ZLEVEL_ASTEROID)
-			continue
-		alarms[++alarms.len] = alarm.get_nano_data_console()
+	if(ticker && ticker.current_state < GAME_STATE_PLAYING && istype(passed_alarm)) // Generating the list for the first time as the game hasn't started - no need to run through the machines list everything every time
+		alarms[++alarms.len] = passed_alarm.get_nano_data_console()
+	else
+		for(var/obj/machinery/alarm/alarm in sortAtom((monitored_alarms ? monitored_alarms : machines)))
+			if(!monitored_alarms && alarm.z != ZLEVEL_STATION && alarm.z != ZLEVEL_ASTEROID)
+				continue
+			alarms[++alarms.len] = alarm.get_nano_data_console()
 		
-	cache_entry.timestamp = world.time + 10 SECONDS
+	cache_entry.timestamp = world.time //+ 10 SECONDS
 	cache_entry.data = alarms		
 	return alarms
 
+/datum/repository/air_alarm/proc/update_cache(var/obj/machinery/alarm/alarm)
+	return air_alarm_data(refresh = 1, passed_alarm = alarm)
\ No newline at end of file
diff --git a/code/datums/cache/powermonitor.dm b/code/datums/cache/powermonitor.dm
index 6ba79d2f78e..a99b380a13d 100644
--- a/code/datums/cache/powermonitor.dm
+++ b/code/datums/cache/powermonitor.dm
@@ -10,8 +10,8 @@ var/global/datum/repository/powermonitor/powermonitor_repository = new()
 
 	if(!refresh)
 		return cache_entry.data
-		
-	for(var/obj/machinery/computer/monitor/pMon in world)
+	
+	for(var/obj/machinery/computer/monitor/pMon in machines)
 		if( !(pMon.stat & (NOPOWER|BROKEN)) )
 			pMonData[++pMonData.len] = list ("Name" = pMon.name, "ref" = "\ref[pMon]")
 
@@ -20,5 +20,5 @@ var/global/datum/repository/powermonitor/powermonitor_repository = new()
 	return pMonData
 	
 /datum/repository/powermonitor/proc/update_cache()
-	return powermonitor_data(1)
+	return powermonitor_data(refresh = 1)
 	
\ No newline at end of file
diff --git a/code/game/area/areas.dm b/code/game/area/areas.dm
index 1a9dcca511e..7dafb778e7a 100644
--- a/code/game/area/areas.dm
+++ b/code/game/area/areas.dm
@@ -66,8 +66,10 @@
 		atmosalm = danger_level
 		for (var/obj/machinery/alarm/AA in src)
 			AA.update_icon()
-
+			
+		air_alarm_repository.update_cache(src)
 		return 1
+	air_alarm_repository.update_cache(src)
 	return 0
 
 /area/proc/air_doors_close()
diff --git a/code/game/machinery/alarm.dm b/code/game/machinery/alarm.dm
index b9abe4e1c1d..45429353bfc 100644
--- a/code/game/machinery/alarm.dm
+++ b/code/game/machinery/alarm.dm
@@ -204,6 +204,10 @@
 /obj/machinery/alarm/Destroy()
 	if(radio_controller)
 		radio_controller.remove_object(src, frequency)
+		
+	if (src in machines) // So the cache can properly update
+		removeAtProcessing()
+	air_alarm_repository.update_cache(src)
 	return ..()
 
 /obj/machinery/alarm/proc/first_run()
@@ -212,6 +216,7 @@
 	if (name == "alarm")
 		name = "[alarm_area.name] Air Alarm"
 	apply_preset(1) // Don't cycle.
+	air_alarm_repository.update_cache(src)
 
 /obj/machinery/alarm/initialize()
 	set_frequency(frequency)
diff --git a/code/game/machinery/computer/power.dm b/code/game/machinery/computer/power.dm
index 138f6b324b9..50a37483526 100644
--- a/code/game/machinery/computer/power.dm
+++ b/code/game/machinery/computer/power.dm
@@ -12,15 +12,21 @@
 	var/datum/nano_module/power_monitor/power_monitor
 
 /obj/machinery/computer/monitor/New()
+	..()
 	power_monitor = new(src)	
 	powernet = find_powernet()
 	powermonitor_repository.update_cache()	
-	..()
 	
 /obj/machinery/computer/monitor/Destroy()
+	if (src in machines) // So the cache can properly update
+		removeAtProcessing()
 	powermonitor_repository.update_cache()	
 	return ..()	
 	
+/obj/machinery/computer/monitor/power_change()
+	..()
+	powermonitor_repository.update_cache()	
+	
 /obj/machinery/computer/monitor/process() 
 	if(!powernet)
 		powernet = find_powernet()
diff --git a/code/game/objects/items/devices/PDA/cart.dm b/code/game/objects/items/devices/PDA/cart.dm
index d71852ddc68..4b69fd2dd6d 100644
--- a/code/game/objects/items/devices/PDA/cart.dm
+++ b/code/game/objects/items/devices/PDA/cart.dm
@@ -285,7 +285,7 @@
 	if(mode==43 || mode==433)						
 		values["powermonitors"] = powermonitor_repository.powermonitor_data()
 
-		if (!isnull(powmonitor.powernet))
+		if (powmonitor && !isnull(powmonitor.powernet))
 			values["powerconnected"] = 1
 			values["poweravail"] = powmonitor.powernet.avail
 			values["powerload"] = num2text(powmonitor.powernet.viewload,10)
diff --git a/code/modules/nano/modules/power_monitor.dm b/code/modules/nano/modules/power_monitor.dm
index 9171ea747ce..1bcf9bc2176 100644
--- a/code/modules/nano/modules/power_monitor.dm
+++ b/code/modules/nano/modules/power_monitor.dm
@@ -20,6 +20,9 @@
 		data["powermonitors"] = powermonitor_repository.powermonitor_data()
 		
 	if (powermonitor && !isnull(powermonitor.powernet))	
+		if(select_monitor && (powermonitor.stat & (NOPOWER|BROKEN)))
+			powermonitor = null
+			return
 		data["poweravail"] = powermonitor.powernet.avail
 		data["powerload"] = num2text(powermonitor.powernet.viewload,10)	
 		data["apcs"] = apc_repository.apc_data(powermonitor)