diff --git a/code/__DEFINES/atmospherics.dm b/code/__DEFINES/atmospherics.dm
index d2988a6474f..fe7e2b0067c 100644
--- a/code/__DEFINES/atmospherics.dm
+++ b/code/__DEFINES/atmospherics.dm
@@ -114,4 +114,9 @@
 
 // Atmos pipe limits
 #define MAX_OUTPUT_PRESSURE					4500 // (kPa) What pressure pumps and powered equipment max out at.
-#define MAX_TRANSFER_RATE					200 // (L/s) Maximum speed powered equipment can work at.
\ No newline at end of file
+#define MAX_TRANSFER_RATE					200 // (L/s) Maximum speed powered equipment can work at.
+
+// Atmos alarm defines
+#define ATMOS_ALARM_NONE					0
+#define ATMOS_ALARM_WARNING					1
+#define ATMOS_ALARM_DANGER					2
\ No newline at end of file
diff --git a/code/game/area/Space Station 13 areas.dm b/code/game/area/Space Station 13 areas.dm
index 8ec413450b0..fd6b0938108 100644
--- a/code/game/area/Space Station 13 areas.dm	
+++ b/code/game/area/Space Station 13 areas.dm	
@@ -17,7 +17,7 @@ NOTE: there are two lists of areas in the end of this file: centcom and station
 
 /area
 	var/fire = null
-	var/atmosalm = 0
+	var/atmosalm = ATMOS_ALARM_NONE
 	var/poweralm = 1
 	var/party = null
 	var/radalert = 0
diff --git a/code/game/area/areas.dm b/code/game/area/areas.dm
index ec70d50c504..eb743afad62 100644
--- a/code/game/area/areas.dm
+++ b/code/game/area/areas.dm
@@ -53,7 +53,7 @@
 
 
 /area/proc/atmosalert(danger_level, var/alarm_source)
-	if(danger_level == 0)
+	if(danger_level == ATMOS_ALARM_NONE)
 		atmosphere_alarm.clearAlarm(src, alarm_source)
 	else
 		atmosphere_alarm.triggerAlarm(src, alarm_source, severity = danger_level)
@@ -64,10 +64,10 @@
 			danger_level = max(danger_level, AA.danger_level)
 
 	if(danger_level != atmosalm)
-		if(danger_level < 1 && atmosalm >= 1)
+		if(danger_level < ATMOS_ALARM_WARNING && atmosalm >= ATMOS_ALARM_WARNING)
 			//closing the doors on red and opening on green provides a bit of hysteresis that will hopefully prevent fire doors from opening and closing repeatedly due to noise
 			air_doors_open()
-		else if(danger_level >= 2 && atmosalm < 2)
+		else if(danger_level >= ATMOS_ALARM_DANGER && atmosalm < ATMOS_ALARM_DANGER)
 			air_doors_close()
 
 		atmosalm = danger_level
@@ -81,9 +81,10 @@
 
 /area/proc/air_doors_close()
 	if(!air_doors_activated)
-		air_doors_activated = 1
+		air_doors_activated = TRUE
 		for(var/obj/machinery/door/firedoor/D in src)
 			if(!D.welded)
+				D.activate_alarm()
 				if(D.operating)
 					D.nextstate = CLOSED
 				else if(!D.density)
@@ -92,9 +93,10 @@
 
 /area/proc/air_doors_open()
 	if(air_doors_activated)
-		air_doors_activated = 0
+		air_doors_activated = FALSE
 		for(var/obj/machinery/door/firedoor/D in src)
 			if(!D.welded)
+				D.deactivate_alarm()
 				if(D.operating)
 					D.nextstate = OPEN
 				else if(D.density)
diff --git a/code/game/machinery/alarm.dm b/code/game/machinery/alarm.dm
index efa6a1ded81..632177d7358 100644
--- a/code/game/machinery/alarm.dm
+++ b/code/game/machinery/alarm.dm
@@ -14,14 +14,14 @@
 
 /datum/tlv/proc/get_danger_level(curval as num)
 	if(max2 >=0 && curval>max2)
-		return 2
+		return ATMOS_ALARM_DANGER
 	if(min2 >=0 && curval<min2)
-		return 2
+		return ATMOS_ALARM_DANGER
 	if(max1 >=0 && curval>max1)
-		return 1
+		return ATMOS_ALARM_WARNING
 	if(min1 >=0 && curval<min1)
-		return 1
-	return 0
+		return ATMOS_ALARM_WARNING
+	return ATMOS_ALARM_NONE
 
 /datum/tlv/proc/CopyFrom(datum/tlv/other)
 	min2 = other.min2
@@ -103,7 +103,7 @@
 	var/screen = AALARM_SCREEN_MAIN
 	var/area_uid
 	var/area/alarm_area
-	var/danger_level = 0
+	var/danger_level = ATMOS_ALARM_NONE
 	var/alarmActivated = 0 // Manually activated (independent from danger level)
 
 	var/buildstage = 2 //2 is built, 1 is building, 0 is frame.
@@ -349,11 +349,11 @@
 		return
 
 	switch(max(danger_level, alarm_area.atmosalm-1))
-		if(0)
+		if(ATMOS_ALARM_NONE)
 			icon_state = "alarm0"
-		if(1)
+		if(ATMOS_ALARM_WARNING)
 			icon_state = "alarm2" //yes, alarm2 is yellow alarm
-		if(2)
+		if(ATMOS_ALARM_DANGER)
 			icon_state = "alarm1"
 
 /obj/machinery/alarm/receive_signal(datum/signal/signal)
@@ -670,21 +670,21 @@
 
 /obj/machinery/alarm/ui_data(mob/user, ui_key = "main", datum/topic_state/state = default_state)
 	var/data[0]
-	var/list/href_list = state.href_list()
 
+	var/list/href_list = state.href_list(user)
 	if(href_list)
 		data["remote_connection"] = href_list["remote_connection"]
 		data["remote_access"] = href_list["remote_access"]
 
 	data["name"] = sanitize(name)
 	data["air"] = ui_air_status()
-	data["alarmActivated"] = alarmActivated || danger_level == 2
+	data["alarmActivated"] = alarmActivated || danger_level == ATMOS_ALARM_DANGER
 	data["thresholds"] = generate_thresholds_menu()
 
 	// Locked when:
 	//   Not sent from atmos console AND
 	//   Not silicon AND locked.
-	data["locked"] = is_locked(user,href_list)
+	data["locked"] = !is_authenticated(user, href_list)
 	data["rcon"] = rcon_setting
 	data["target_temp"] = target_temperature - T0C
 	data["atmos_alarm"] = alarm_area.atmosalm
@@ -799,16 +799,6 @@
 	else
 		return !locked
 
-/obj/machinery/alarm/proc/is_locked(mob/user as mob, href_list)
-	if(user.can_admin_interact())
-		return 0
-	else if(is_auth_rcon(href_list))
-		return 0
-	else if(isAI(user) || isrobot(user))
-		return 0
-	else
-		return locked
-
 /obj/machinery/alarm/proc/is_auth_rcon(href_list)
 	if(href_list && href_list["remote_connection"] && href_list["remote_access"])
 		return 1
@@ -914,15 +904,15 @@
 		return 1
 
 	if(href_list["atmos_alarm"])
-		if(alarm_area.atmosalert(2, src))
-			apply_danger_level(2)
+		if(alarm_area.atmosalert(ATMOS_ALARM_DANGER, src))
+			apply_danger_level(ATMOS_ALARM_DANGER)
 		alarmActivated = 1
 		update_icon()
 		return 1
 
 	if(href_list["atmos_reset"])
-		if(alarm_area.atmosalert(0, src))
-			apply_danger_level(0)
+		if(alarm_area.atmosalert(ATMOS_ALARM_NONE, src))
+			apply_danger_level(ATMOS_ALARM_NONE)
 		alarmActivated = 0
 		update_icon()
 		return 1
diff --git a/code/game/machinery/doors/door.dm b/code/game/machinery/doors/door.dm
index 0d1488acad6..fe0d1a37b47 100644
--- a/code/game/machinery/doors/door.dm
+++ b/code/game/machinery/doors/door.dm
@@ -21,6 +21,8 @@
 	var/autoclose_timer
 	var/glass = 0
 	var/normalspeed = 1
+	var/auto_close_time = 150
+	var/auto_close_time_dangerous = 5
 	var/heat_proof = 0 // For glass airlocks/opacity firedoors
 	var/emergency = 0
 	var/air_properties_vary_with_direction = 0
@@ -231,7 +233,7 @@
 
 	// The `addtimer` system has the advantage of being cancelable
 	if(autoclose)
-		autoclose_timer = addtimer(src, "autoclose", normalspeed ? 150 : 5, unique = 1)
+		autoclose_timer = addtimer(src, "autoclose", normalspeed ? auto_close_time : auto_close_time_dangerous, unique = 1)
 
 	return 1
 
diff --git a/code/game/machinery/doors/firedoor.dm b/code/game/machinery/doors/firedoor.dm
index 526ad96cde4..c9538303490 100644
--- a/code/game/machinery/doors/firedoor.dm
+++ b/code/game/machinery/doors/firedoor.dm
@@ -13,17 +13,22 @@
 	icon = 'icons/obj/doors/Doorfireglass.dmi'
 	icon_state = "door_open"
 	opacity = 0
-	density = 0
-	heat_proof = 1
-	glass = 1
+	density = FALSE
+	heat_proof = TRUE
+	glass = TRUE
 	power_channel = ENVIRON
 	closed_layer = 3.11
+	auto_close_time = 50
 
+	var/can_force = TRUE
+	var/force_open_time = 300
+	var/can_crush = TRUE
 	var/assembly_type = /obj/structure/firelock_frame	
 	var/nextstate = null
-	var/welded = 0
-	var/boltslocked = 1
-	var/can_deconstruct = 1
+	var/welded = FALSE
+	var/boltslocked = TRUE
+	var/can_deconstruct = TRUE
+	var/active_alarm = FALSE
 
 /obj/machinery/door/firedoor/Bumped(atom/AM)
 	if(p_open || operating)	
@@ -38,7 +43,7 @@
 		latetoggle()
 	else
 		stat |= NOPOWER
-	return
+	update_icon()
 
 /obj/machinery/door/firedoor/attackby(obj/item/weapon/C as obj, mob/user as mob, params)
 	add_fingerprint(user)
@@ -85,20 +90,34 @@
 			if(!F.wielded)
 				return
 
+		user.visible_message("[user] forces \the [src] with [C].",
+		"You force \the [src] with [C].")				
 		if(density)
+			autoclose = TRUE
 			open()
 		else
 			close()
 
 /obj/machinery/door/firedoor/attack_hand(mob/user)		
-	add_fingerprint(user)
-	if(welded || operating || stat & NOPOWER)
+	if(operating || !density)
 		return
-	if(density)
-		open()
-	else
-		close()
-		
+
+	add_fingerprint(user)
+	
+	if(can_force && (!glass || user.a_intent != I_HELP))
+		user.visible_message("<span class='notice'>[user] begins forcing \the [src].</span>", \
+							 "<span class='notice'>You begin forcing \the [src].</span>")	
+		if(do_after(user, force_open_time, target = src))
+			user.visible_message("<span class='notice'>[user] forces \the [src].</span>", \
+								 "<span class='notice'>You force \the [src].</span>")
+			autoclose = TRUE
+			open()
+	else if(glass)
+		user.changeNext_move(CLICK_CD_MELEE)
+		user.visible_message("<span class='warning'>[user] bangs on \the [src].</span>",
+							 "<span class='warning'>You bang on \the [src].</span>")
+		playsound(get_turf(src), 'sound/effects/Glassknock.ogg', 10, 1)			
+
 /obj/machinery/door/firedoor/attack_ai(mob/user)
 	attack_hand(user)
 	
@@ -122,6 +141,8 @@
 
 /obj/machinery/door/firedoor/update_icon()
 	overlays.Cut()
+	if(active_alarm && !(stat & NOPOWER))
+		overlays += image('icons/obj/doors/Doorfire.dmi', "alarmlights")
 	if(density)
 		icon_state = "door_closed"
 		if(welded)
@@ -130,6 +151,14 @@
 		icon_state = "door_open"
 		if(welded)
 			overlays += "welded_open"
+			
+/obj/machinery/door/firedoor/proc/activate_alarm()
+	active_alarm = TRUE
+	update_icon()
+	
+/obj/machinery/door/firedoor/proc/deactivate_alarm()
+	active_alarm = FALSE
+	update_icon()
 
 /obj/machinery/door/firedoor/open()
 	. = ..()
@@ -137,7 +166,13 @@
 
 /obj/machinery/door/firedoor/close()
 	. = ..()
+	if(can_crush)
+		crush()
 	latetoggle()
+	
+/obj/machinery/door/firedoor/autoclose()
+	if(active_alarm)
+		. = ..()
 
 /obj/machinery/door/firedoor/proc/latetoggle()
 	if(operating || stat & NOPOWER || !nextstate)
@@ -163,6 +198,7 @@
 /obj/machinery/door/firedoor/border_only	
 	icon = 'icons/obj/doors/edge_Doorfire.dmi'
 	flags = ON_BORDER
+	can_crush = FALSE
 
 /obj/machinery/door/firedoor/border_only/CanPass(atom/movable/mover, turf/target, height=0)
 	if(istype(mover) && mover.checkpass(PASSGLASS))
@@ -189,9 +225,10 @@
 /obj/machinery/door/firedoor/heavy
 	name = "heavy firelock"
 	icon = 'icons/obj/doors/Doorfire.dmi'
-	glass = 0
+	glass = FALSE
 	opacity = 1
 	assembly_type = /obj/structure/firelock_frame/heavy
+	can_force = FALSE
 	
 /obj/machinery/door/firedoor/heavy/ex_act(severity)
 	switch(severity)
diff --git a/code/modules/nano/modules/atmos_control.dm b/code/modules/nano/modules/atmos_control.dm
index 0670193e498..9dbb508f16e 100644
--- a/code/modules/nano/modules/atmos_control.dm
+++ b/code/modules/nano/modules/atmos_control.dm
@@ -25,7 +25,7 @@
 		if(ui_ref)
 			var/obj/machinery/alarm/alarm = locate(href_list["alarm"]) in (monitored_alarms ? monitored_alarms : machines)
 			if(alarm)
-				var/datum/topic_state/TS = generate_state(alarm)
+				var/datum/topic_state/air_alarm/TS = generate_state(alarm)
 				alarm.ui_interact(usr, master_ui = ui_ref, state = TS)
 
 /datum/nano_module/atmos_control/ui_interact(mob/user, ui_key = "main", var/datum/nanoui/ui = null, var/force_open = 1, var/master_ui = null, var/datum/topic_state/state = default_state)
@@ -63,7 +63,7 @@
 
 /datum/topic_state/air_alarm/href_list(var/mob/user)
 	var/list/extra_href = list()
-	extra_href["remote_connection"] = 1
+	extra_href["remote_connection"] = TRUE
 	extra_href["remote_access"] = has_access(user)
 
 	return extra_href
diff --git a/icons/obj/doors/Doorfire.dmi b/icons/obj/doors/Doorfire.dmi
index 1f3999b774e..94ec8b967fb 100644
Binary files a/icons/obj/doors/Doorfire.dmi and b/icons/obj/doors/Doorfire.dmi differ