diff --git a/code/__DEFINES/atmospherics_defines.dm b/code/__DEFINES/atmospherics_defines.dm
index 97a736cbfc2e..eff495a06658 100644
--- a/code/__DEFINES/atmospherics_defines.dm
+++ b/code/__DEFINES/atmospherics_defines.dm
@@ -156,6 +156,7 @@
 #define ATMOS_MODE_SPACE 0						//! Tile is exposed to space and loses air every second
 #define ATMOS_MODE_SEALED 1						//! Tile has no special behaviour
 #define ATMOS_MODE_EXPOSED_TO_ENVIRONMENT 2		//! Tile is exposed to the environment, ex: lavaland
+#define ATMOS_MODE_NO_DECAY 3					//! Prevents hot tiles from automatically decaying towards T20C.
 
 /// Lavaland environment: hot, low pressure.
 #define ENVIRONMENT_LAVALAND "lavaland"
diff --git a/milla.dll b/milla.dll
index 956df9e5f228..7fe9470ef3dd 100755
Binary files a/milla.dll and b/milla.dll differ
diff --git a/milla/src/api.rs b/milla/src/api.rs
index db0bbe6206ac..53e63d4a17a9 100644
--- a/milla/src/api.rs
+++ b/milla/src/api.rs
@@ -239,6 +239,7 @@ pub(crate) fn internal_set_tile(
                     };
                 }
             }
+			3 => tile.mode = AtmosMode::NoDecay,
             _ => return Err(eyre!("Invalid atmos_mode: {}", value)),
         }
     }
diff --git a/milla/src/model.rs b/milla/src/model.rs
index d8aa7b1c519a..8f559783e27f 100644
--- a/milla/src/model.rs
+++ b/milla/src/model.rs
@@ -130,6 +130,8 @@ pub(crate) enum AtmosMode {
     Sealed,
     /// Tile is exposed to the given environment.
     ExposedTo { environment_id: u8 },
+	/// Prevents hot tiles from automatically decaying towards T20C
+	NoDecay,
 }
 
 impl From<AtmosMode> for ByondValue {
@@ -138,6 +140,7 @@ impl From<AtmosMode> for ByondValue {
             AtmosMode::Space => ByondValue::from(0.0),
             AtmosMode::Sealed => ByondValue::from(1.0),
             AtmosMode::ExposedTo { .. } => ByondValue::from(2.0),
+			AtmosMode::NoDecay => ByondValue::from(3.0),
         }
     }
 }
diff --git a/milla/src/simulate.rs b/milla/src/simulate.rs
index 7eb359b4a271..b8c88dc80aa6 100644
--- a/milla/src/simulate.rs
+++ b/milla/src/simulate.rs
@@ -437,6 +437,7 @@ pub(crate) fn apply_tile_mode(
                 my_inactive_tile.thermal_energy *= 1.0 - SPACE_COOLING_FACTOR;
             }
         }
+		AtmosMode::NoDecay => {} // No special interactions
     }
     Ok(())
 }
diff --git a/tools/ci/libmilla_ci.so b/tools/ci/libmilla_ci.so
index 877c0069516d..8517035dea12 100755
Binary files a/tools/ci/libmilla_ci.so and b/tools/ci/libmilla_ci.so differ