diff --git a/src/B1DetectorConstruction.cc b/src/B1DetectorConstruction.cc
index 287eae65325648ac4fb9a20a51e8662482d8e44b..04e3be92f9ac50c78b1de8b9a4b72a81beadd119 100644
--- a/src/B1DetectorConstruction.cc
+++ b/src/B1DetectorConstruction.cc
@@ -29,7 +29,7 @@
 
 #include "B1DetectorConstruction.hh"
 #include "B1SD.hh"
-
+#include "G4Material.hh"
 #include "G4RunManager.hh"
 #include "G4NistManager.hh"
 #include "G4Box.hh"
@@ -41,11 +41,13 @@
 #include "G4LogicalVolume.hh"
 #include "G4PVPlacement.hh"
 #include "G4SystemOfUnits.hh"
+#include "G4PhysicalConstants.hh"
 #include "G4VSensitiveDetector.hh"
 #include "G4Track.hh"
 #include "G4UniformMagField.hh"
 #include "G4FieldManager.hh"
 #include "G4TransportationManager.hh"
+#include "G4Element.hh"
 
 
 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
@@ -67,6 +69,30 @@ G4VPhysicalVolume* B1DetectorConstruction::Construct()
   // Get nist material manager
   G4NistManager* nist = G4NistManager::Instance();
 
+  //making air materiais
+  //Nitrogen
+  G4double a_N = 14.01*g/mole;
+  G4String name, symbol;
+  G4double z;
+  G4Element* ele_N = new G4Element(name="Nitrogen", symbol="N", z=7., a_N);
+  //Oxygen
+  G4double a_o = 16.00*g/mole;
+  G4Element* ele_O = new G4Element(name="Oxygen", symbol="O", z=8., a_o);
+  //Argon
+  G4double a_Ar = 39.948*g/mole;
+  G4Element* ele_Ar = new G4Element(name="Argon", symbol="Ar", z=18., a_Ar);
+
+  G4int num_layers;
+  G4double altitude = 100*km;
+  G4double layer_delta_h = num_layers/altitude;
+  std::vector<G4Material *> layers_material;
+  layers_material.reserve(num_layers);
+
+  for(G4int i = 0; i < num_layers; i++) {
+    //fazer if clause para verificar valor de delta h progressivamente.
+    //dependendo do h + delta_h -> parâmetros diferentes.
+
+  }
 
   // Option to switch on/off checking of volumes overlaps
   //
@@ -82,7 +108,8 @@ G4VPhysicalVolume* B1DetectorConstruction::Construct()
   G4double h = 100*m;
   G4double theta_0 = 0.*deg;
   G4double theta_f = 360.*deg;
-  G4Material* world_mat = nist->FindOrBuildMaterial("G4_AIR");
+  //making world of vacuum
+  G4Material* world_mat = nist->FindOrBuildMaterial("G4_Galactic");
 
 
   G4Tubs* cilindro = new G4Tubs("world", raio_i, raio_e, h, theta_0, theta_f);
@@ -107,6 +134,11 @@ G4VPhysicalVolume* B1DetectorConstruction::Construct()
   //
    fScoringVolume = logicWorld;
 
+   //começar aqui os layers da atmosfera em um for semelhante ao dos detetores, porém grudados e preenchendo todo o cilindro.
+
+
+
+
 
   G4double safe_distance = 0.02*m;
   //Coloque aqui o número de detetores