diff --git a/JPSfire/generic/FDSMeshStorage.cpp b/JPSfire/generic/FDSMeshStorage.cpp
index 7dbcceac66ef90d9d4936f8eeee28d93100e3204..aaff1754ce5c56cb985de41533c63f375da46d49 100644
--- a/JPSfire/generic/FDSMeshStorage.cpp
+++ b/JPSfire/generic/FDSMeshStorage.cpp
@@ -273,7 +273,7 @@ const FDSMesh &FDSMeshStorage::GetFDSMesh(const double &pedElev, const Point &do
 {
     //Smoke Sensor active
 
-     std::string quantity = "dx_1.00";
+     std::string quantity = "EXTINCTION_COEFFICIENT";
 
     _PedEyeHeight = pedElev + 1.8;
     GetNearestHeight(_PedEyeHeight);