diff --git a/code/controllers/configuration/entries/general.dm b/code/controllers/configuration/entries/general.dm
index d828457fa7..182394bfa4 100644
--- a/code/controllers/configuration/entries/general.dm
+++ b/code/controllers/configuration/entries/general.dm
@@ -342,3 +342,6 @@
 /datum/config_entry/number/hard_deletes_overrun_limit
 	default = 0
 	min_val = 0
+
+/datum/config_entry/flag/atmos_equalize_enabled
+	default = FALSE
diff --git a/code/controllers/subsystem/air.dm b/code/controllers/subsystem/air.dm
index 91e92feee9..c79f9523c0 100644
--- a/code/controllers/subsystem/air.dm
+++ b/code/controllers/subsystem/air.dm
@@ -108,6 +108,7 @@ SUBSYSTEM_DEF(air)
 	setup_atmos_machinery()
 	setup_pipenets()
 	gas_reactions = init_gas_reactions()
+	should_do_equalization = CONFIG_GET(flag/atmos_equalize_enabled)
 	auxtools_update_reactions()
 	return ..()
 
diff --git a/config/entries/general.txt b/config/entries/general.txt
index b3130565e4..b426881de9 100644
--- a/config/entries/general.txt
+++ b/config/entries/general.txt
@@ -497,3 +497,6 @@ PAI_CUSTOM_HOLOFORMS
 
 ## Once a typepath causes overrun from hard deletes this many times, stop hard deleting it on garbage collection failures. (set to 0 to disable)
 #HARD_DELETES_OVERRUN_LIMIT 0
+
+## Enables monstermos/"equalization" step in atmos.
+# ATMOS_EQUALIZATION_ENABLED