Adds a breathing sound when you're in low pressure.

code/_helpers/turfs.dm

@@ -72,3 +72,10 @@
 
 /proc/is_station_turf(var/turf/T)
 	return T && isStationLevel(T.z)
+
+/proc/is_below_sound_pressure(var/turf/T)
+	var/datum/gas_mixture/environment = T ? T.return_air() : null
+	var/pressure =  environment ? environment.return_pressure() : 0
+	if(pressure < SOUND_MINIMUM_PRESSURE)
+		return TRUE
+	return FALSE

code/modules/mob/living/carbon/human/species/species.dm

@@ -118,6 +118,7 @@
 	var/warning_low_pressure = WARNING_LOW_PRESSURE   // Low pressure warning.
 	var/hazard_low_pressure = HAZARD_LOW_PRESSURE     // Dangerously low pressure.
 	var/light_dam                                     // If set, mob will be damaged in light over this value and heal in light below its negative.
+	var/breathing_sound = 'sound/voice/monkey.ogg'    // If set, this mob will have a breathing sound.
 	var/body_temperature = 310.15	                  // Non-IS_SYNTHETIC species will try to stabilize at this temperature.
 	                                                  // (also affects temperature processing)
 

code/modules/mob/living/carbon/human/species/station/vaurca/vaurca.dm

@@ -41,6 +41,7 @@
 	breath_vol_mul = 1/6 // 0.5 liters * breath_vol_mul = breath volume
 	breath_eff_mul = 6 // 1/6 * breath_eff_mul = fraction of gas consumed
 	poison_type = "nitrogen" //a species that breathes plasma shouldn't be poisoned by it.
+	breathing_sound = null //They don't work that way I guess? I'm a coder not a purple man.
 	mob_size = 13 //their half an inch thick exoskeleton and impressive height, plus all of their mechanical organs.
 	natural_climbing = TRUE
 	climb_coeff = 0.75

code/modules/organs/internal/lungs.dm

@@ -249,6 +249,13 @@
 	else
 		last_successful_breath = world.time
 		owner.oxygen_alert = 0
+		if(!BP_IS_ROBOTIC(src) && species.breathing_sound && is_below_sound_pressure(get_turf(owner)))
+			if(breathing || owner.shock_stage >= 10)
+				sound_to(owner, sound(species.breathing_sound,0,0,0,5))
+				breathing = 0
+			else
+				breathing = 1
+
 	return failed_breath
 
 /obj/item/organ/internal/lungs/proc/handle_temperature_effects(datum/gas_mixture/breath)