diff --git a/sumo_project/SUMOFactory.py b/sumo_project/SUMOFactory.py
index 9d2efd7..4037fb0 100644
--- a/sumo_project/SUMOFactory.py
+++ b/sumo_project/SUMOFactory.py
@@ -1,40 +1,29 @@
 '''
 Created on 17 oct. 2018
 
-@author: Admin
+@author: Axel Huynh-Phuc, Thibaud Gasser
 '''
-import os, sys
-import traci 
-from shapely.geometry import Polygon
-from shapely.geometry import Point
+
+import traci
 from shapely.geometry.linestring import LineString
 
 
 class SUMOFactory(object):
     
-    def __init__(self):
-        '''Constructor'''
-    
-    def stopVehicle(self, veh_id):
+    def stop_vehicle(self, veh_id):
         traci.vehicle.remove(veh_id, traci.constants.REMOVE_PARKING)
-        
-    def getLanesIntoArea(self, area):
-        polygon_area = Polygon(area)
-        lanes = []
+
+    def lanes_in_area(self, area):
+        polygon_area = area.rectangle
         for lane_id in traci.lane.getIDList():
             polygon_lane = LineString(traci.lane.getShape(lane_id))
             if polygon_area.intersects(polygon_lane):
-                print("lane is in area : ", polygon_lane)
-                lanes.append(lane_id)
-        return lanes
+                yield lane_id
            
     def lock_area(self, area):
-        lanes = self.getLanesIntoArea(area)
-        for lane_id in lanes:
-            '''print("Vehicles number into lane =  ", traci.lane.getLastStepVehicleNumber(lane_id))
-            if traci.lane.getLastStepVehicleNumber(lane_id) == 0:
-                traci.lane.setDisallowed(lane_id, "passenger")
-                print("lane blocked : ", lane_id)'''
-            traci.lane.setMaxSpeed(lane_id, 30) 
-            for veh_id in traci.vehicle.getIDList(): 
-                traci.vehicle.rerouteTraveltime(veh_id, True)
+        for lane_id in self.lanes_in_area(area):
+            print(f'Setting max speed of {lane_id} to 30.')
+            traci.lane.setMaxSpeed(lane_id, 30)
+
+        for veh_id in traci.vehicle.getIDList():
+            traci.vehicle.rerouteTraveltime(veh_id, True)
diff --git a/sumo_project/emissions.py b/sumo_project/emissions.py
new file mode 100644
index 0000000..e76ac22
--- /dev/null
+++ b/sumo_project/emissions.py
@@ -0,0 +1,68 @@
+import os
+import sys
+
+from SUMOFactory import SUMOFactory
+
+if 'SUMO_HOME' in os.environ:
+    tools = os.path.join(os.environ['SUMO_HOME'], 'tools')
+    sys.path.append(tools)
+else:
+    sys.exit("please declare environment variable 'SUMO_HOME'")
+
+import traci
+from area import Area
+
+sumoBinary = os.path.join(os.environ['SUMO_HOME'], 'bin', 'sumo-gui')
+sumoCmd = [sumoBinary, "-c", "mulhouse_simulation/map.sumocfg"]
+CELLS_NUMBER = 10
+CO2_THRESHOLD = 500000
+
+
+def init_grid(simulation_bounds, cells_number):
+    width = simulation_bounds[1][0] / cells_number
+    height = simulation_bounds[1][1] / cells_number
+    # TODO: change data structure?
+    areas = list()
+    for i in range(cells_number):
+        for j in range(cells_number):
+            # bounds coordinates for the area : (xmin, ymin, xmax, ymax)
+            ar_bounds = ((i * width, j * height), (i * width, (j + 1) * height),
+                         ((i + 1) * width, (j + 1) * height), ((i + 1) * width, j * height))
+            area = Area(ar_bounds)
+            area.name = 'area{}{}'.format(i, j)
+            areas.append(area)
+            traci.polygon.add(area.name, ar_bounds, (0, 255, 0))
+    return areas
+
+
+def emission_for_area(area):
+    # retrieve all vehicles into this area
+    for veh_id in traci.vehicle.getIDList():
+        pos = traci.vehicle.getPosition(veh_id)
+        if area.contains(pos):
+            area.emissions += traci.vehicle.getCO2Emission(veh_id)
+
+
+def get_emissions(areas, factory):
+    for area in areas:
+        emission_for_area(area)
+        if area.emissions > CO2_THRESHOLD:
+            # print(f'Threshold exceeded in {area.name} : {area.emissions}')
+            factory.lock_area(area)
+            traci.polygon.setColor(area.name, (255, 0, 0))
+            traci.polygon.setFilled(area.name, True)
+
+
+def main():
+    try:
+        traci.start(sumoCmd)
+        grid = init_grid(traci.simulation.getNetBoundary(), CELLS_NUMBER)
+        while traci.simulation.getMinExpectedNumber() > 0:
+            traci.simulationStep()
+            get_emissions(grid, SUMOFactory())
+    finally:
+        traci.close(False)
+
+
+if __name__ == '__main__':
+    main()