diff --git a/data/json/items/comestibles/drink.json b/data/json/items/comestibles/drink.json
index 564934f366325..57c3d12aedaf1 100644
--- a/data/json/items/comestibles/drink.json
+++ b/data/json/items/comestibles/drink.json
@@ -1524,9 +1524,10 @@
     "description": "Fresh, clean water.  Truly the best thing to quench your thirst.",
     "container": "bottle_plastic",
     "sealed": true,
-    "revert_to": "water",
+    "color": "light_cyan",
+    "//": "Clean water becomes regular water in about 4 weeks if exposed to air (1 week if outdoors).",
     "properties": { "max_air_exposure_hours": "720" },
-    "color": "light_cyan"
+    "revert_to": "water"
   },
   {
     "id": "water_spring",
diff --git a/src/item.cpp b/src/item.cpp
index e57af2fd36b90..f6148b305114f 100644
--- a/src/item.cpp
+++ b/src/item.cpp
@@ -8025,12 +8025,13 @@ void item::calc_rot_while_processing( time_duration processing_duration )
     last_temp_check += processing_duration;
 }
 
-bool item::process_decay_in_air( Character *carrier, int max_air_exposure_hours,
+bool item::process_decay_in_air( map& here, Character *carrier, const tripoint& pos, int max_air_exposure_hours,
                                  time_duration time_delta )
 {
     if( !has_own_flag( flag_FROZEN ) ) {
+        double environment_multiplier = here.is_outside(pos) ? 2.0 : 1.0;
         time_duration new_air_exposure = time_duration::from_seconds( item_counter ) + time_delta *
-                                         rng_normal( 0.9, 1.1 );
+                                         rng_normal( 0.9, 1.1 ) * environment_multiplier;
         if( new_air_exposure >= time_duration::from_hours( max_air_exposure_hours ) ) {
             convert( *type->revert_to, carrier );
             return true;
diff --git a/src/item.h b/src/item.h
index c90af9fb877e2..0942c8ffcd9ed 100644
--- a/src/item.h
+++ b/src/item.h
@@ -3074,7 +3074,7 @@ class item : public visitable
         bool process_blackpowder_fouling( Character *carrier );
         bool process_gun_cooling( Character *carrier );
         bool process_tool( Character *carrier, const tripoint &pos );
-        bool process_decay_in_air( Character *carrier, int max_air_exposure_hours,
+        bool process_decay_in_air( map& here, Character *carrier, const tripoint& pos, int max_air_exposure_hours,
                                    time_duration time_delta );