More and more Destroy() cleanups all across the board - Return qdel hints.

code/game/objects/items/weapons/material/material_armor.dm

@@ -42,7 +42,7 @@ Protectiveness | Armor %
 
 /obj/item/clothing/Destroy()
 	processing_objects -= src
-	..()
+	return ..()
 
 /obj/item/clothing/get_material()
 	return material

code/game/objects/items/weapons/mop_deploy.dm

@@ -26,7 +26,7 @@
 			T.dirt = 0
 		for(var/obj/effect/O in src)
 			if(istype(O,/obj/effect/rune) || istype(O,/obj/effect/decal/cleanable) || istype(O,/obj/effect/overlay))
-				del(O)
+				qdel(O)
 /*	//Reagent code changed at some point and the below doesn't work.  To be fixed later.
 	source.reagents.reaction(src, TOUCH, 10)	//10 is the multiplier for the reaction effect. probably needed to wet the floor properly.
 	source.reagents.remove_any(1)				//reaction() doesn't use up the reagents
@@ -47,16 +47,16 @@
 		return
 	..()
 
-/obj/item/weapon/mop_deploy/Del()
+/obj/item/weapon/mop_deploy/Destroy()
 	processing_objects -= src
-	..()
+	. = ..()
 
 /obj/item/weapon/mop_deploy/attack_self(mob/user as mob)
 	user.drop_from_inventory(src)
-	spawn(1) if(src) del(src)
+	spawn(1) if(!QDELETED(src)) qdel(src)
 
 /obj/item/weapon/mop_deploy/dropped()
-	spawn(1) if(src) del(src)
+	spawn(1) if(!QDELETED(src)) qdel(src)
 
 /obj/item/weapon/mop_deploy/process()
 	if(!creator || loc != creator || !creator.item_is_in_hands(src))
@@ -71,4 +71,4 @@
 			host.pinned -= src
 			host.embedded -= src
 			host.drop_from_inventory(src)
-		spawn(1) if(src) del(src)
+		spawn(1) if(!QDELETED(src)) qdel(src)

code/game/objects/items/weapons/storage/internal.dm

@@ -12,7 +12,7 @@
 
 /obj/item/weapon/storage/internal/Destroy()
 	master_item = null
-	..()
+	. = ..()
 
 /obj/item/weapon/storage/internal/attack_hand()
 	return		//make sure this is never picked up

code/game/objects/items/weapons/storage/storage.dm

@@ -38,15 +38,15 @@
 
 /obj/item/weapon/storage/Destroy()
 	close_all()
-	qdel(boxes)
-	qdel(src.storage_start)
-	qdel(src.storage_continue)
-	qdel(src.storage_end)
-	qdel(src.stored_start)
-	qdel(src.stored_continue)
-	qdel(src.stored_end)
-	qdel(closer)
-	..()
+	qdel_null(boxes)
+	qdel_null(src.storage_start)
+	qdel_null(src.storage_continue)
+	qdel_null(src.storage_end)
+	qdel_null(src.stored_start)
+	qdel_null(src.stored_continue)
+	qdel_null(src.stored_end)
+	qdel_null(closer)
+	. = ..()
 
 /obj/item/weapon/storage/MouseDrop(obj/over_object as obj)
 	if(!canremove)

code/game/objects/items/weapons/tanks/tanks.dm

@@ -44,8 +44,7 @@ var/list/global/tank_gauge_cache = list()
 	return
 
 /obj/item/weapon/tank/Destroy()
-	if(air_contents)
-		qdel(air_contents)
+	qdel_null(air_contents)
 
 	processing_objects.Remove(src)
 
@@ -53,7 +52,7 @@ var/list/global/tank_gauge_cache = list()
 		var/obj/item/device/transfer_valve/TTV = loc
 		TTV.remove_tank(src)
 
-	..()
+	return ..()
 
 /obj/item/weapon/tank/examine(mob/user)
 	. = ..(user, 0)