On ring roads
							                                
                                        
                                    
							                        
                    
                            In road tunnels
							                                
                                        
                                    
							                        
                    
                            In dead ground
							                                
                                        
                                    
							                        
                    
                            On high-level roads
							                                
                                        
                                    
							                        
                     
	 
	