diff --git a/code/__DEFINES/reactions.dm b/code/__DEFINES/reactions.dm
index 869882e762f..5973eab8b82 100644
--- a/code/__DEFINES/reactions.dm
+++ b/code/__DEFINES/reactions.dm
@@ -48,3 +48,4 @@
 #define FUSION_RAD_MAX						2000
 #define FUSION_RAD_COEFFICIENT				(-1000)
 #define FUSION_INSTABILITY_ENDOTHERMALITY   2
+#define FUSION_MAXIMUM_TEMPERATURE			1e8
diff --git a/code/modules/atmospherics/gasmixtures/reactions.dm b/code/modules/atmospherics/gasmixtures/reactions.dm
index 67ee93422b3..bae795a68be 100644
--- a/code/modules/atmospherics/gasmixtures/reactions.dm
+++ b/code/modules/atmospherics/gasmixtures/reactions.dm
@@ -302,7 +302,9 @@
 
 	reaction_energy += delta_plasma*PLASMA_BINDING_ENERGY //Energy is gained or lost corresponding to the creation or destruction of mass.
 	if(instability < FUSION_INSTABILITY_ENDOTHERMALITY)
-		reaction_energy = max(reaction_energy,0) //Stable reactions don't end up endothermic.
+		reaction_energy = max(reaction_energy,0) //Stable reactions don't end up exothermic.
+	else if(air.temperature > FUSION_MAXIMUM_TEMPERATURE && reaction_energy > 0) //Makes the reaction neutral if above max temp.
+		reaction_energy = 0
 	else if (reaction_energy < 0)
 		reaction_energy *= (instability-FUSION_INSTABILITY_ENDOTHERMALITY)**0.5