diff --git a/baystation12.dme b/baystation12.dme
index 712a0adaaf..430d3b1377 100644
--- a/baystation12.dme
+++ b/baystation12.dme
@@ -1325,14 +1325,20 @@
 #include "code\WorkInProgress\Ported\policetape.dm"
 #include "code\WorkInProgress\SkyMarshal\officer_stuff.dm"
 #include "code\WorkInProgress\SkyMarshal\Ultralight_procs.dm"
+#include "code\ZAS\_docs.dm"
+#include "code\ZAS\_gas_mixture.dm"
 #include "code\ZAS\Airflow.dm"
+#include "code\ZAS\Atom.dm"
 #include "code\ZAS\Connection.dm"
+#include "code\ZAS\ConnectionGroup.dm"
+#include "code\ZAS\Controller.dm"
 #include "code\ZAS\Debug.dm"
+#include "code\ZAS\Diagnostic.dm"
 #include "code\ZAS\Fire.dm"
-#include "code\ZAS\Functions.dm"
 #include "code\ZAS\Plasma.dm"
+#include "code\ZAS\Turf.dm"
 #include "code\ZAS\Variable Settings.dm"
-#include "code\ZAS\ZAS_Zones.dm"
+#include "code\ZAS\Zone.dm"
 #include "interface\interface.dm"
 #include "interface\skin.dmf"
 #include "maps\tgstation2.dmm"
diff --git a/baystation12.int b/baystation12.int
index 4be4a21dee..27f246accb 100644
--- a/baystation12.int
+++ b/baystation12.int
@@ -1,7 +1,9 @@
 // BEGIN_INTERNALS
 /*
 MAP_ICON_TYPE: 0
-DIR: code 
+WINDOW: code\ZAS\_gas_mixture.dm;code\ZAS\Airflow.dm;code\ZAS\Atom.dm;code\ZAS\Connection.dm;code\ZAS\ConnectionGroup.dm;code\ZAS\Controller.dm;code\ZAS\Debug.dm;code\ZAS\Diagnostic.dm;code\ZAS\Fire.dm;code\ZAS\Plasma.dm;code\ZAS\Turf.dm;code\ZAS\Variable Settings.dm;code\ZAS\Zone.dm;code\ZAS\_docs.dm;code\modules\admin\verbs\mapping.dm;code\game\turfs\turf.dm;code\modules\admin\verbs\diagnostics.dm;code\game\machinery\shieldgen.dm;code\game\machinery\doors\door.dm;code\game\machinery\doors\windowdoor.dm;code\game\objects\effects\effect_system.dm;code\game\objects\structures\mineral_doors.dm;code\game\objects\structures\windoor_assembly.dm;code\game\objects\structures\window.dm
+DIR: code code\game\machinery code\game\machinery\doors code\game\objects code\game\objects\effects code\game\objects\structures code\modules\admin\verbs code\ZAS 
+FILE: code\ZAS\Zone.dm
 AUTO_FILE_DIR: OFF
 */
 // END_INTERNALS
diff --git a/code/ZAS/Connection.dm b/code/ZAS/Connection.dm
index 2615effaa2..64f6faba14 100644
--- a/code/ZAS/Connection.dm
+++ b/code/ZAS/Connection.dm
@@ -32,12 +32,6 @@
 		if(EAST) E = c
 		if(WEST) W = c
 
-/connection_managerproc/close(d)
-	if(check(N) && (NORTH & d) && !N.direct()) N.erase()
-	if(check(S) && (SOUTH & d) && !S.direct()) S.erase()
-	if(check(E) && (EAST & d) && !E.direct()) E.erase()
-	if(check(W) && (WEST & d) && !W.direct()) W.erase()
-
 /connection_manager/proc/update_all()
 	if(check(N)) N.update()
 	if(check(S)) S.update()
diff --git a/code/ZAS/ConnectionGroup.dm b/code/ZAS/ConnectionGroup.dm
index 360372a83a..2a4c374f78 100644
--- a/code/ZAS/ConnectionGroup.dm
+++ b/code/ZAS/ConnectionGroup.dm
@@ -153,192 +153,192 @@
 var/list/sharing_lookup_table = list(0.30, 0.40, 0.48, 0.54, 0.60, 0.66)
 
 proc/ShareRatio(datum/gas_mixture/A, datum/gas_mixture/B, connecting_tiles)
-//Shares a specific ratio of gas between mixtures using simple weighted averages.
-var
+	//Shares a specific ratio of gas between mixtures using simple weighted averages.
+	var
+		//WOOT WOOT TOUCH THIS AND YOU ARE A RETARD
+		ratio = sharing_lookup_table[6]
+		//WOOT WOOT TOUCH THIS AND YOU ARE A RETARD
+
+		size = max(1,A.group_multiplier)
+		share_size = max(1,B.group_multiplier)
+
+		full_oxy = A.oxygen * size
+		full_nitro = A.nitrogen * size
+		full_co2 = A.carbon_dioxide * size
+		full_plasma = A.toxins * size
+
+		full_heat_capacity = A.heat_capacity() * size
+
+		s_full_oxy = B.oxygen * share_size
+		s_full_nitro = B.nitrogen * share_size
+		s_full_co2 = B.carbon_dioxide * share_size
+		s_full_plasma = B.toxins * share_size
+
+		s_full_heat_capacity = B.heat_capacity() * share_size
+
+		oxy_avg = (full_oxy + s_full_oxy) / (size + share_size)
+		nit_avg = (full_nitro + s_full_nitro) / (size + share_size)
+		co2_avg = (full_co2 + s_full_co2) / (size + share_size)
+		plasma_avg = (full_plasma + s_full_plasma) / (size + share_size)
+
+		temp_avg = (A.temperature * full_heat_capacity + B.temperature * s_full_heat_capacity) / (full_heat_capacity + s_full_heat_capacity)
+
 	//WOOT WOOT TOUCH THIS AND YOU ARE A RETARD
-	ratio = sharing_lookup_table[6]
+	if(sharing_lookup_table.len >= connecting_tiles) //6 or more interconnecting tiles will max at 42% of air moved per tick.
+		ratio = sharing_lookup_table[connecting_tiles]
 	//WOOT WOOT TOUCH THIS AND YOU ARE A RETARD
 
-	size = max(1,A.group_multiplier)
-	share_size = max(1,B.group_multiplier)
+	A.oxygen = max(0, (A.oxygen - oxy_avg) * (1-ratio) + oxy_avg )
+	A.nitrogen = max(0, (A.nitrogen - nit_avg) * (1-ratio) + nit_avg )
+	A.carbon_dioxide = max(0, (A.carbon_dioxide - co2_avg) * (1-ratio) + co2_avg )
+	A.toxins = max(0, (A.toxins - plasma_avg) * (1-ratio) + plasma_avg )
 
-	full_oxy = A.oxygen * size
-	full_nitro = A.nitrogen * size
-	full_co2 = A.carbon_dioxide * size
-	full_plasma = A.toxins * size
+	A.temperature = max(0, (A.temperature - temp_avg) * (1-ratio) + temp_avg )
 
-	full_heat_capacity = A.heat_capacity() * size
+	B.oxygen = max(0, (B.oxygen - oxy_avg) * (1-ratio) + oxy_avg )
+	B.nitrogen = max(0, (B.nitrogen - nit_avg) * (1-ratio) + nit_avg )
+	B.carbon_dioxide = max(0, (B.carbon_dioxide - co2_avg) * (1-ratio) + co2_avg )
+	B.toxins = max(0, (B.toxins - plasma_avg) * (1-ratio) + plasma_avg )
 
-	s_full_oxy = B.oxygen * share_size
-	s_full_nitro = B.nitrogen * share_size
-	s_full_co2 = B.carbon_dioxide * share_size
-	s_full_plasma = B.toxins * share_size
+	B.temperature = max(0, (B.temperature - temp_avg) * (1-ratio) + temp_avg )
 
-	s_full_heat_capacity = B.heat_capacity() * share_size
+	for(var/datum/gas/G in A.trace_gases)
+		var/datum/gas/H = locate(G.type) in B.trace_gases
+		if(H)
+			var/G_avg = (G.moles*size + H.moles*share_size) / (size+share_size)
+			G.moles = (G.moles - G_avg) * (1-ratio) + G_avg
 
-	oxy_avg = (full_oxy + s_full_oxy) / (size + share_size)
-	nit_avg = (full_nitro + s_full_nitro) / (size + share_size)
-	co2_avg = (full_co2 + s_full_co2) / (size + share_size)
-	plasma_avg = (full_plasma + s_full_plasma) / (size + share_size)
+			H.moles = (H.moles - G_avg) * (1-ratio) + G_avg
+		else
+			H = new G.type
+			B.trace_gases += H
+			var/G_avg = (G.moles*size) / (size+share_size)
+			G.moles = (G.moles - G_avg) * (1-ratio) + G_avg
+			H.moles = (H.moles - G_avg) * (1-ratio) + G_avg
 
-	temp_avg = (A.temperature * full_heat_capacity + B.temperature * s_full_heat_capacity) / (full_heat_capacity + s_full_heat_capacity)
+	for(var/datum/gas/G in B.trace_gases)
+		var/datum/gas/H = locate(G.type) in A.trace_gases
+		if(!H)
+			H = new G.type
+			A.trace_gases += H
+			var/G_avg = (G.moles*size) / (size+share_size)
+			G.moles = (G.moles - G_avg) * (1-ratio) + G_avg
+			H.moles = (H.moles - G_avg) * (1-ratio) + G_avg
 
-//WOOT WOOT TOUCH THIS AND YOU ARE A RETARD
-if(sharing_lookup_table.len >= connecting_tiles) //6 or more interconnecting tiles will max at 42% of air moved per tick.
-	ratio = sharing_lookup_table[connecting_tiles]
-//WOOT WOOT TOUCH THIS AND YOU ARE A RETARD
+	A.update_values()
+	B.update_values()
 
-A.oxygen = max(0, (A.oxygen - oxy_avg) * (1-ratio) + oxy_avg )
-A.nitrogen = max(0, (A.nitrogen - nit_avg) * (1-ratio) + nit_avg )
-A.carbon_dioxide = max(0, (A.carbon_dioxide - co2_avg) * (1-ratio) + co2_avg )
-A.toxins = max(0, (A.toxins - plasma_avg) * (1-ratio) + plasma_avg )
-
-A.temperature = max(0, (A.temperature - temp_avg) * (1-ratio) + temp_avg )
-
-B.oxygen = max(0, (B.oxygen - oxy_avg) * (1-ratio) + oxy_avg )
-B.nitrogen = max(0, (B.nitrogen - nit_avg) * (1-ratio) + nit_avg )
-B.carbon_dioxide = max(0, (B.carbon_dioxide - co2_avg) * (1-ratio) + co2_avg )
-B.toxins = max(0, (B.toxins - plasma_avg) * (1-ratio) + plasma_avg )
-
-B.temperature = max(0, (B.temperature - temp_avg) * (1-ratio) + temp_avg )
-
-for(var/datum/gas/G in A.trace_gases)
-	var/datum/gas/H = locate(G.type) in B.trace_gases
-	if(H)
-		var/G_avg = (G.moles*size + H.moles*share_size) / (size+share_size)
-		G.moles = (G.moles - G_avg) * (1-ratio) + G_avg
-
-		H.moles = (H.moles - G_avg) * (1-ratio) + G_avg
-	else
-		H = new G.type
-		B.trace_gases += H
-		var/G_avg = (G.moles*size) / (size+share_size)
-		G.moles = (G.moles - G_avg) * (1-ratio) + G_avg
-		H.moles = (H.moles - G_avg) * (1-ratio) + G_avg
-
-for(var/datum/gas/G in B.trace_gases)
-	var/datum/gas/H = locate(G.type) in A.trace_gases
-	if(!H)
-		H = new G.type
-		A.trace_gases += H
-		var/G_avg = (G.moles*size) / (size+share_size)
-		G.moles = (G.moles - G_avg) * (1-ratio) + G_avg
-		H.moles = (H.moles - G_avg) * (1-ratio) + G_avg
-
-A.update_values()
-B.update_values()
-
-if(A.compare(B)) return 1
-else return 0
+	if(A.compare(B)) return 1
+	else return 0
 
 proc/ShareSpace(datum/gas_mixture/A, list/unsimulated_tiles, dbg_output)
-//A modified version of ShareRatio for spacing gas at the same rate as if it were going into a large airless room.
-if(!unsimulated_tiles)
-	return 0
-
-var
-	unsim_oxygen = 0
-	unsim_nitrogen = 0
-	unsim_co2 = 0
-	unsim_plasma = 0
-	unsim_heat_capacity = 0
-	unsim_temperature = 0
-
-	size = max(1,A.group_multiplier)
-
-var/tileslen
-var/share_size
-
-if(istype(unsimulated_tiles, /datum/gas_mixture))
-	var/datum/gas_mixture/avg_unsim = unsimulated_tiles
-	unsim_oxygen = avg_unsim.oxygen
-	unsim_co2 = avg_unsim.carbon_dioxide
-	unsim_nitrogen = avg_unsim.nitrogen
-	unsim_plasma = avg_unsim.toxins
-	unsim_temperature = avg_unsim.temperature
-	share_size = max(1, max(size + 3, 1) + avg_unsim.group_multiplier)
-	tileslen = avg_unsim.group_multiplier
-
-else if(istype(unsimulated_tiles, /list))
-	if(!unsimulated_tiles.len)
+	//A modified version of ShareRatio for spacing gas at the same rate as if it were going into a large airless room.
+	if(!unsimulated_tiles)
 		return 0
-	// We use the same size for the potentially single space tile
-	// as we use for the entire room. Why is this?
-	// Short answer: We do not want larger rooms to depressurize more
-	// slowly than small rooms, preserving our good old "hollywood-style"
-	// oh-shit effect when large rooms get breached, but still having small
-	// rooms remain pressurized for long enough to make escape possible.
-	share_size = max(1, max(size + 3, 1) + unsimulated_tiles.len)
-	var/correction_ratio = share_size / unsimulated_tiles.len
 
-	for(var/turf/T in unsimulated_tiles)
-		unsim_oxygen += T.oxygen
-		unsim_co2 += T.carbon_dioxide
-		unsim_nitrogen += T.nitrogen
-		unsim_plasma += T.toxins
-		unsim_temperature += T.temperature/unsimulated_tiles.len
+	var
+		unsim_oxygen = 0
+		unsim_nitrogen = 0
+		unsim_co2 = 0
+		unsim_plasma = 0
+		unsim_heat_capacity = 0
+		unsim_temperature = 0
 
-	//These values require adjustment in order to properly represent a room of the specified size.
-	unsim_oxygen *= correction_ratio
-	unsim_co2 *= correction_ratio
-	unsim_nitrogen *= correction_ratio
-	unsim_plasma *= correction_ratio
-	tileslen = unsimulated_tiles.len
+		size = max(1,A.group_multiplier)
 
-else //invalid input type
-	return 0
+	var/tileslen
+	var/share_size
 
-unsim_heat_capacity = HEAT_CAPACITY_CALCULATION(unsim_oxygen, unsim_co2, unsim_nitrogen, unsim_plasma)
+	if(istype(unsimulated_tiles, /datum/gas_mixture))
+		var/datum/gas_mixture/avg_unsim = unsimulated_tiles
+		unsim_oxygen = avg_unsim.oxygen
+		unsim_co2 = avg_unsim.carbon_dioxide
+		unsim_nitrogen = avg_unsim.nitrogen
+		unsim_plasma = avg_unsim.toxins
+		unsim_temperature = avg_unsim.temperature
+		share_size = max(1, max(size + 3, 1) + avg_unsim.group_multiplier)
+		tileslen = avg_unsim.group_multiplier
 
-var
-	ratio = sharing_lookup_table[6]
+	else if(istype(unsimulated_tiles, /list))
+		if(!unsimulated_tiles.len)
+			return 0
+		// We use the same size for the potentially single space tile
+		// as we use for the entire room. Why is this?
+		// Short answer: We do not want larger rooms to depressurize more
+		// slowly than small rooms, preserving our good old "hollywood-style"
+		// oh-shit effect when large rooms get breached, but still having small
+		// rooms remain pressurized for long enough to make escape possible.
+		share_size = max(1, max(size + 3, 1) + unsimulated_tiles.len)
+		var/correction_ratio = share_size / unsimulated_tiles.len
 
-	old_pressure = A.return_pressure()
+		for(var/turf/T in unsimulated_tiles)
+			unsim_oxygen += T.oxygen
+			unsim_co2 += T.carbon_dioxide
+			unsim_nitrogen += T.nitrogen
+			unsim_plasma += T.toxins
+			unsim_temperature += T.temperature/unsimulated_tiles.len
 
-	full_oxy = A.oxygen * size
-	full_nitro = A.nitrogen * size
-	full_co2 = A.carbon_dioxide * size
-	full_plasma = A.toxins * size
+		//These values require adjustment in order to properly represent a room of the specified size.
+		unsim_oxygen *= correction_ratio
+		unsim_co2 *= correction_ratio
+		unsim_nitrogen *= correction_ratio
+		unsim_plasma *= correction_ratio
+		tileslen = unsimulated_tiles.len
 
-	full_heat_capacity = A.heat_capacity() * size
+	else //invalid input type
+		return 0
 
-	oxy_avg = (full_oxy + unsim_oxygen) / (size + share_size)
-	nit_avg = (full_nitro + unsim_nitrogen) / (size + share_size)
-	co2_avg = (full_co2 + unsim_co2) / (size + share_size)
-	plasma_avg = (full_plasma + unsim_plasma) / (size + share_size)
+	unsim_heat_capacity = HEAT_CAPACITY_CALCULATION(unsim_oxygen, unsim_co2, unsim_nitrogen, unsim_plasma)
 
-	temp_avg = 0
+	var
+		ratio = sharing_lookup_table[6]
 
-if((full_heat_capacity + unsim_heat_capacity) > 0)
-	temp_avg = (A.temperature * full_heat_capacity + unsim_temperature * unsim_heat_capacity) / (full_heat_capacity + unsim_heat_capacity)
+		old_pressure = A.return_pressure()
 
-if(sharing_lookup_table.len >= tileslen) //6 or more interconnecting tiles will max at 42% of air moved per tick.
-	ratio = sharing_lookup_table[tileslen]
+		full_oxy = A.oxygen * size
+		full_nitro = A.nitrogen * size
+		full_co2 = A.carbon_dioxide * size
+		full_plasma = A.toxins * size
 
-A.oxygen = max(0, (A.oxygen - oxy_avg) * (1 - ratio) + oxy_avg )
-A.nitrogen = max(0, (A.nitrogen - nit_avg) * (1 - ratio) + nit_avg )
-A.carbon_dioxide = max(0, (A.carbon_dioxide - co2_avg) * (1 - ratio) + co2_avg )
-A.toxins = max(0, (A.toxins - plasma_avg) * (1 - ratio) + plasma_avg )
+		full_heat_capacity = A.heat_capacity() * size
 
-A.temperature = max(TCMB, (A.temperature - temp_avg) * (1 - ratio) + temp_avg )
+		oxy_avg = (full_oxy + unsim_oxygen) / (size + share_size)
+		nit_avg = (full_nitro + unsim_nitrogen) / (size + share_size)
+		co2_avg = (full_co2 + unsim_co2) / (size + share_size)
+		plasma_avg = (full_plasma + unsim_plasma) / (size + share_size)
 
-for(var/datum/gas/G in A.trace_gases)
-	var/G_avg = (G.moles * size) / (size + share_size)
-	G.moles = (G.moles - G_avg) * (1 - ratio) + G_avg
+		temp_avg = 0
 
-A.update_values()
+	if((full_heat_capacity + unsim_heat_capacity) > 0)
+		temp_avg = (A.temperature * full_heat_capacity + unsim_temperature * unsim_heat_capacity) / (full_heat_capacity + unsim_heat_capacity)
 
-return abs(old_pressure - A.return_pressure())
+	if(sharing_lookup_table.len >= tileslen) //6 or more interconnecting tiles will max at 42% of air moved per tick.
+		ratio = sharing_lookup_table[tileslen]
+
+	A.oxygen = max(0, (A.oxygen - oxy_avg) * (1 - ratio) + oxy_avg )
+	A.nitrogen = max(0, (A.nitrogen - nit_avg) * (1 - ratio) + nit_avg )
+	A.carbon_dioxide = max(0, (A.carbon_dioxide - co2_avg) * (1 - ratio) + co2_avg )
+	A.toxins = max(0, (A.toxins - plasma_avg) * (1 - ratio) + plasma_avg )
+
+	A.temperature = max(TCMB, (A.temperature - temp_avg) * (1 - ratio) + temp_avg )
+
+	for(var/datum/gas/G in A.trace_gases)
+		var/G_avg = (G.moles * size) / (size + share_size)
+		G.moles = (G.moles - G_avg) * (1 - ratio) + G_avg
+
+	A.update_values()
+
+	return abs(old_pressure - A.return_pressure())
 
 
 proc/ShareHeat(datum/gas_mixture/A, datum/gas_mixture/B, connecting_tiles)
-//This implements a simplistic version of the Stefan-Boltzmann law.
-var/energy_delta = ((A.temperature - B.temperature) ** 4) * 5.6704e-8 * connecting_tiles * 2.5
-var/maximum_energy_delta = max(0, min(A.temperature * A.heat_capacity() * A.group_multiplier, B.temperature * B.heat_capacity() * B.group_multiplier))
-if(maximum_energy_delta > abs(energy_delta))
-	if(energy_delta < 0)
-		maximum_energy_delta *= -1
-	energy_delta = maximum_energy_delta
+	//This implements a simplistic version of the Stefan-Boltzmann law.
+	var/energy_delta = ((A.temperature - B.temperature) ** 4) * 5.6704e-8 * connecting_tiles * 2.5
+	var/maximum_energy_delta = max(0, min(A.temperature * A.heat_capacity() * A.group_multiplier, B.temperature * B.heat_capacity() * B.group_multiplier))
+	if(maximum_energy_delta > abs(energy_delta))
+		if(energy_delta < 0)
+			maximum_energy_delta *= -1
+		energy_delta = maximum_energy_delta
 
-A.temperature -= energy_delta / (A.heat_capacity() * A.group_multiplier)
-B.temperature += energy_delta / (B.heat_capacity() * B.group_multiplier)
\ No newline at end of file
+	A.temperature -= energy_delta / (A.heat_capacity() * A.group_multiplier)
+	B.temperature += energy_delta / (B.heat_capacity() * B.group_multiplier)
\ No newline at end of file
diff --git a/code/ZAS/Controller.dm b/code/ZAS/Controller.dm
index a4ff7d6aaf..b02e256033 100644
--- a/code/ZAS/Controller.dm
+++ b/code/ZAS/Controller.dm
@@ -2,29 +2,25 @@ var/datum/controller/air_system/air_master
 
 var/tick_multiplier = 2
 
-var/tolerance_temp = 1
-var/tolerance_kpa = 1
-var/mimic_rate = 2
 
-/datum/controller/air_system
-	//Geometry lists
-	var/list/zones = list()
-	var/list/edges = list()
+//Geometry lists
+/datum/controller/air_system/var/list/zones = list()
+/datum/controller/air_system/var/list/edges = list()
 
-	//Geometry updates lists
-	var/list/tiles_to_update = list()
-	var/list/zones_to_update = list()
-	var/list/active_hotspots = list()
+//Geometry updates lists
+/datum/controller/air_system/var/list/tiles_to_update = list()
+/datum/controller/air_system/var/list/zones_to_update = list()
+/datum/controller/air_system/var/list/active_hotspots = list()
 
-	var/active_zones = 0
+/datum/controller/air_system/var/active_zones = 0
 
-	var/current_cycle = 0
-	var/update_delay = 5 //How long between check should it try to process atmos again.
-	var/failed_ticks = 0 //How many ticks have runtimed?
+/datum/controller/air_system/var/current_cycle = 0
+/datum/controller/air_system/var/update_delay = 5 //How long between check should it try to process atmos again.
+/datum/controller/air_system/var/failed_ticks = 0 //How many ticks have runtimed?
 
-	var/tick_progress = 0
+/datum/controller/air_system/var/tick_progress = 0
 
-	var/next_id = 1
+/datum/controller/air_system/var/next_id = 1 //Used to keep track of zone UIDs.
 
 /datum/controller/air_system/proc/Setup()
 	//Purpose: Call this at the start to setup air groups geometry
@@ -148,12 +144,12 @@ Total Unsimulated Turfs: [world.maxx*world.maxy*world.maxz - simulated_turf_coun
 	if(.)
 		tick_progress = "success"
 
-/datum/controller/air_system/proc/new_zone(zone/z)
+/datum/controller/air_system/proc/add_zone(zone/z)
 	zones.Add(z)
 	z.name = "Zone [next_id++]"
 	mark_zone_update(z)
 
-/datum/controller/air_system/proc/invalid_zone(zone/z)
+/datum/controller/air_system/proc/remove_zone(zone/z)
 	zones.Remove(z)
 
 /datum/controller/air_system/proc/air_blocked(turf/A, turf/B)
@@ -169,7 +165,7 @@ Total Unsimulated Turfs: [world.maxx*world.maxy*world.maxz - simulated_turf_coun
 	#ifdef ZASDBG
 	ASSERT(istype(T))
 	#endif
-	return T.zone && !T.zone.invalid
+	return istype(T) && T.zone && !T.zone.invalid
 
 /datum/controller/air_system/proc/merge(zone/A, zone/B)
 	#ifdef ZASDBG
@@ -240,14 +236,7 @@ Total Unsimulated Turfs: [world.maxx*world.maxy*world.maxz - simulated_turf_coun
 	Z.needs_update = 1
 
 /datum/controller/air_system/proc/equivalent_pressure(zone/A, zone/B)
-	if(abs(A.air.return_pressure() - B.air.return_pressure()) > tolerance_kpa) return 0
-	if(abs(A.air.temperature - B.air.temperature) > tolerance_temp) return 0
-	return 1
-
-/datum/controller/air_system/proc/equalize(zone/A, zone/B)
-	A.air.share(B.air)
-	mark_zone_update(A)
-	mark_zone_update(B)
+	return A.air.compare(B.air)
 
 /datum/controller/air_system/proc/active_zones()
 	return active_zones
diff --git a/code/ZAS/Zone.dm b/code/ZAS/Zone.dm
index 605dfce30a..9567a31704 100644
--- a/code/ZAS/Zone.dm
+++ b/code/ZAS/Zone.dm
@@ -2,7 +2,6 @@
 /zone/var/name
 /zone/var/invalid = 0
 /zone/var/list/contents = list()
-/zone/var/list/unsimulated_contents = list()
 
 /zone/var/needs_update = 0
 
@@ -11,7 +10,7 @@
 /zone/var/datum/gas_mixture/air = new
 
 /zone/New()
-	air_master.new_zone(src)
+	air_master.add_zone(src)
 	air.temperature = TCMB
 	air.group_multiplier = 1
 	air.volume = CELL_VOLUME
@@ -29,15 +28,6 @@
 	contents.Add(T)
 	T.set_graphic(air.graphic)
 
-
-/zone/proc/add_unsimulated(turf/T)
-#ifdef ZASDBG
-	ASSERT(!invalid)
-	ASSERT(istype(T))
-	ASSERT(!istype(T,/turf/simulated))
-#endif
-	unsimulated_contents |= T
-
 /zone/proc/remove(turf/simulated/T)
 #ifdef ZASDBG
 	ASSERT(!invalid)
@@ -64,11 +54,10 @@
 		#ifdef ZASDBG
 		T.dbg(merged)
 		#endif
-	into.unsimulated_contents |= unsimulated_contents
 
 /zone/proc/c_invalidate()
 	invalid = 1
-	air_master.invalid_zone(src)
+	air_master.remove_zone(src)
 	#ifdef ZASDBG
 	for(var/turf/simulated/T in contents)
 		T.dbg(invalid_zone)
diff --git a/code/ZAS/_docs.dm b/code/ZAS/_docs.dm
new file mode 100644
index 0000000000..1df7759fcc
--- /dev/null
+++ b/code/ZAS/_docs.dm
@@ -0,0 +1,18 @@
+/*
+
+Zone Air System:
+
+This air system divides the station into impermeable areas called zones.
+When something happens, i.e. a door opening or a wall being taken down,
+zones equalize and eventually merge. Making an airtight area closes the connection again.
+
+Important Functions:
+
+air_master.mark_for_update(turf)
+	When stuff happens, call this. It works on everything.
+
+*/
+
+#define AIR_BLOCKED 1
+#define ZONE_BLOCKED 2
+#define BLOCKED 3
\ No newline at end of file
diff --git a/code/game/machinery/doors/door.dm b/code/game/machinery/doors/door.dm
index d3f276abe0..950871d983 100644
--- a/code/game/machinery/doors/door.dm
+++ b/code/game/machinery/doors/door.dm
@@ -268,7 +268,7 @@
 
 	for(var/turf/simulated/turf in locs)
 		update_heat_protection(turf)
-		air_master.AddTurfToUpdate(turf)
+		air_master.mark_for_update(turf)
 
 	return 1
 
diff --git a/code/game/machinery/doors/windowdoor.dm b/code/game/machinery/doors/windowdoor.dm
index c8d0d4d110..152d6de60c 100644
--- a/code/game/machinery/doors/windowdoor.dm
+++ b/code/game/machinery/doors/windowdoor.dm
@@ -18,7 +18,7 @@
 	if(!air_master)
 		return 0
 
-	air_master.AddTurfToUpdate(get_turf(src))
+	air_master.mark_for_update(get_turf(src))
 
 	return 1
 
diff --git a/code/game/machinery/shieldgen.dm b/code/game/machinery/shieldgen.dm
index 03d97e0e1f..972066d1fb 100644
--- a/code/game/machinery/shieldgen.dm
+++ b/code/game/machinery/shieldgen.dm
@@ -30,7 +30,7 @@
 	if(!air_master)
 		return 0
 
-	air_master.AddTurfToUpdate(get_turf(src))
+	air_master.mark_for_update(get_turf(src))
 
 	return 1
 
diff --git a/code/game/objects/effects/effect_system.dm b/code/game/objects/effects/effect_system.dm
index 499bb2c22a..159a4266dd 100644
--- a/code/game/objects/effects/effect_system.dm
+++ b/code/game/objects/effects/effect_system.dm
@@ -833,7 +833,7 @@ steam.start() -- spawns the effect
 		if(!air_master)
 			return 0
 
-		air_master.AddTurfToUpdate(get_turf(src))
+		air_master.mark_for_update(get_turf(src))
 
 		return 1
 
diff --git a/code/game/objects/structures/mineral_doors.dm b/code/game/objects/structures/mineral_doors.dm
index 64e9623fca..3cdc4765e6 100644
--- a/code/game/objects/structures/mineral_doors.dm
+++ b/code/game/objects/structures/mineral_doors.dm
@@ -158,7 +158,7 @@
 	proc/update_nearby_tiles(need_rebuild) //Copypasta from airlock code
 		if(!air_master)
 			return 0
-		air_master.AddTurfToUpdate(get_turf(src))
+		air_master.mark_for_update(get_turf(src))
 		return 1
 
 /obj/structure/mineral_door/iron
diff --git a/code/game/objects/structures/windoor_assembly.dm b/code/game/objects/structures/windoor_assembly.dm
index f13f3f1dec..e9ae0567bc 100644
--- a/code/game/objects/structures/windoor_assembly.dm
+++ b/code/game/objects/structures/windoor_assembly.dm
@@ -297,6 +297,6 @@ obj/structure/windoor_assembly/Del()
 	if(!air_master)
 		return 0
 
-	air_master.AddTurfToUpdate(loc)
+	air_master.mark_for_update(loc)
 
 	return 1
diff --git a/code/game/objects/structures/window.dm b/code/game/objects/structures/window.dm
index 482fdea6c0..7050808fb4 100644
--- a/code/game/objects/structures/window.dm
+++ b/code/game/objects/structures/window.dm
@@ -313,7 +313,7 @@
 /obj/structure/window/proc/update_nearby_tiles(need_rebuild)
 	if(!air_master)
 		return 0
-	air_master.AddTurfToUpdate(get_turf(src))
+	air_master.mark_for_update(get_turf(src))
 
 	return 1
 
diff --git a/code/game/turfs/turf.dm b/code/game/turfs/turf.dm
index 14b05c7298..ff47a1fa72 100644
--- a/code/game/turfs/turf.dm
+++ b/code/game/turfs/turf.dm
@@ -206,7 +206,7 @@
 		for(var/obj/effect/landmark/zcontroller/c in controller)
 			if(c.down)
 				var/turf/below = locate(src.x, src.y, c.down_target)
-				if((below.zone || zone) && !istype(below, /turf/space)) // dont make open space into space, its pointless and makes people drop out of the station
+				if((air_master.has_valid_zone(below) || air_master.has_valid_zone(src)) && !istype(below, /turf/space)) // dont make open space into space, its pointless and makes people drop out of the station
 					var/turf/W = src.ChangeTurf(/turf/simulated/floor/open)
 					var/list/temp = list()
 					temp += W
@@ -219,10 +219,10 @@
 	if(ispath(N, /turf/simulated/floor))
 		//if the old turf had a zone, connect the new turf to it as well - Cael
 		//Adjusted by SkyMarshal 5/10/13 - The air master will handle the addition of the new turf.
-		if(zone)
-			zone.RemoveTurf(src)
-			if(!zone.CheckStatus())
-				zone.SetStatus(ZONE_ACTIVE)
+		//if(zone)
+		//	zone.RemoveTurf(src)
+		//	if(!zone.CheckStatus())
+		//		zone.SetStatus(ZONE_ACTIVE)
 
 		var/turf/simulated/W = new N( locate(src.x, src.y, src.z) )
 		//W.Assimilate_Air()
@@ -236,16 +236,16 @@
 			W.RemoveLattice()
 
 		if(air_master)
-			air_master.AddTurfToUpdate(src)
+			air_master.mark_for_update(src)
 
 		W.levelupdate()
 		return W
 
 	else
-		if(zone)
-			zone.RemoveTurf(src)
-			if(!zone.CheckStatus())
-				zone.SetStatus(ZONE_ACTIVE)
+		//if(zone)
+		//	zone.RemoveTurf(src)
+		//	if(!zone.CheckStatus())
+		//		zone.SetStatus(ZONE_ACTIVE)
 
 		var/turf/W = new N( locate(src.x, src.y, src.z) )
 		W.lighting_lumcount += old_lumcount
@@ -254,7 +254,7 @@
 			lighting_controller.changed_turfs += W
 
 		if(air_master)
-			air_master.AddTurfToUpdate(src)
+			air_master.mark_for_update(src)
 
 		W.levelupdate()
 		return W
diff --git a/code/modules/admin/verbs/diagnostics.dm b/code/modules/admin/verbs/diagnostics.dm
index 29840d0e61..bbf74c9dbb 100644
--- a/code/modules/admin/verbs/diagnostics.dm
+++ b/code/modules/admin/verbs/diagnostics.dm
@@ -6,7 +6,7 @@
 		alert(usr,"Master_controller or air_master not found.","Air Report")
 		return
 
-	var/active_groups = air_master.active_zones.len
+	var/active_groups = air_master.active_zones
 	var/inactive_groups = air_master.zones.len - active_groups
 
 	var/hotspots = 0
@@ -18,7 +18,7 @@
 	for(var/zone/zone in air_master.zones)
 		var/turf/simulated/turf = locate() in zone.contents
 		if(turf && turf.z == 1)
-			if(zone.status)
+			if(zone.needs_update)
 				active_on_main_station++
 			else
 				inactive_on_main_station++
diff --git a/code/modules/admin/verbs/mapping.dm b/code/modules/admin/verbs/mapping.dm
index 76f1b42046..7b952382a5 100644
--- a/code/modules/admin/verbs/mapping.dm
+++ b/code/modules/admin/verbs/mapping.dm
@@ -162,7 +162,7 @@ var/intercom_range_display_status = 0
 	src.verbs += /client/proc/Zone_Info
 	src.verbs += /client/proc/Test_ZAS_Connection
 	src.verbs += /client/proc/ZoneTick
-	src.verbs += /client/proc/TestZASRebuild
+	//src.verbs += /client/proc/TestZASRebuild
 	//src.verbs += /client/proc/cmd_admin_rejuvenate
 
 	feedback_add_details("admin_verb","mDV") //If you are copy-pasting this, ensure the 2nd parameter is unique to the new proc!