diff --git a/Content.Server/Explosion/EntitySystems/ExplosionGridTileFlood.cs b/Content.Server/Explosion/EntitySystems/ExplosionGridTileFlood.cs
index fa36858ad5..b67c619c1a 100644
--- a/Content.Server/Explosion/EntitySystems/ExplosionGridTileFlood.cs
+++ b/Content.Server/Explosion/EntitySystems/ExplosionGridTileFlood.cs
@@ -186,7 +186,11 @@ public sealed class ExplosionGridTileFlood : ExplosionTileFlood
             NewBlockedTiles.Add(tile);
 
             // At what explosion iteration would this blocker be destroyed?
-            var clearIteration = iteration + (int) MathF.Ceiling(tileData.ExplosionTolerance[_typeIndex] / _intensityStepSize);
+            var required = tileData.ExplosionTolerance[_typeIndex];
+            if (required > _maxIntensity)
+                return; // blocker is never destroyed.
+
+            var clearIteration = iteration + (int) MathF.Ceiling(required / _intensityStepSize);
             if (FreedTileLists.TryGetValue(clearIteration, out var list))
                 list.Add(tile);
             else
@@ -275,7 +279,7 @@ public sealed class ExplosionGridTileFlood : ExplosionTileFlood
 
             // This tile has one or more airtight entities anchored to it blocking the explosion from traveling in
             // some directions. First, check whether this blocker can even be destroyed by this explosion?
-            if (sealIntegrity > _maxIntensity || float.IsNaN(sealIntegrity))
+            if (sealIntegrity > _maxIntensity)
                 continue;
 
             // At what explosion iteration would this blocker be destroyed?
diff --git a/Content.Server/Explosion/EntitySystems/ExplosionSystem.Airtight.cs b/Content.Server/Explosion/EntitySystems/ExplosionSystem.Airtight.cs
index 6ebcf59f2e..aabc78b743 100644
--- a/Content.Server/Explosion/EntitySystems/ExplosionSystem.Airtight.cs
+++ b/Content.Server/Explosion/EntitySystems/ExplosionSystem.Airtight.cs
@@ -147,10 +147,7 @@ public sealed partial class ExplosionSystem : EntitySystem
             foreach (var (type, value) in explosionType.DamagePerIntensity.DamageDict)
             {
                 if (!damageable.Damage.DamageDict.ContainsKey(type))
-                {
-                    explosionTolerance[index] = float.MaxValue;
                     continue;
-                }
 
                 var ev = new GetExplosionResistanceEvent(explosionType.ID);
                 RaiseLocalEvent(uid, ev, false);